Grip pressure and POI Shift

[Jesting Devil]

Had an interesting moment at the range the other day.

I don't shoot bullseye at long range very often but I pushed out to 25yards with my work gun while on a lunch break. First 5 shots, I shot with a fairly relaxed grip, just worrying about a smooth trigger press and holding still. Not exactly limp-writing it but not a super solid grip either. I called each shot fairly close to center but the resulting group was between 2 and 5in high, and 5-6in wide.

I usually shoot alright at longer ranges so I loaded another 5, bore down harder and shot a nice 3.5ish group right in the middle, calling the shots about the same as before, the only difference being grip pressure. I've always assumed that the bullet would be long gone by the time recoil would shift the POI by any noticeable amount but that seems to not be the case. I usually shoot at little dots up close or USPSA targets and always with some time pressure so I'm usually gripping as hard as possible but I didn't think that was helpful shooting untimed groups freestyle. Is this a known thing that I was just not aware of??

I'll try to replicate the results when I shoot again later this week with some different guns as well, maybe it was a fluke and I just suck. Always possible!

Apologies for the lack of photos, I thought of taking one only after throwing out the target.

Gun is a G23 gen 3 with a NY trigger spring (mandated by work) with Ameriglo .125 pro-glo yellow with the .180 operator rear. Success with these sights also surprised me as I usually like a tighter sight picture for longer shots but they seem to work out ok in practice.

[Jeff22]

Pat McNamara calls grip "the forgotten fundamental"

Earlier this year, I noticed if I was shooting a string of more than three rounds, my shots were going left at about 9 o'clock. (I'm right handed).

I was at a class (Glock Operator) and the instructor watched me for a while and told me that my problem was inconsistent grip pressure with my support hand. If I was trying to go fast my grip was firm, but if I was shooting a five or six shot string, my grip pressure lessened in the middle and the shots went left.

He said you can slap the trigger or jerk the trigger all you want but if your grip is firm and consistent and the gun mount is stable then your shots will be centered.

Lots of times I think we presume that a trigger control problem causes all misses and in reality there are more factors in play

[GJM]

Alternatively, wouldn’t another explanation be that your strong grip is camouflaging an imperfection in your trigger press?

[GJM]

It seems like the Glock trigger is especially challenging to press without disturbing the sights, and many of the references to strong grip come from Glock shooters. Interestingly, last week I was listening to a pod cast with Eric Grauffel, and he said he consciously does not grip hard, because a strong grip with his support hand transmits tension to his trigger finger. Robbie Leatham says you can shoot A’s with a terrible grip, it just has to be slower than with a good grip. Interesting topic!

[CraigS]

...Robbie Leatham says you can shoot A’s with a terrible grip, it just has to be slower than with a good grip. Interesting topic!
I haven't noticed a change in POI w/ grip pressure but I sure agree w/ Leatham. Been shooting mostly our 92s for about 18 yrs mostly at paper at an indoor range. So a relaxed grip was fine and it's not like we have to work to absorb the recoil. But spring of 2017 started doing some very low key local Steel and two IDPA matches. So I quickly found I need to grip the crap out of the gun w/ my support hand. Otherwise it takes forever to get the sights back on target. Next range trip I will try varying grip to see if it changes POI.

[Robinson]

Since a recent class I attended where these things were discussed, I've been really trying to focus on the fundamentals of grip and isolating the trigger finger. I've noticed an improvement in my shooting as a result of this, especially by very intentionally applying those two principles in that order. During all this, I've observed that for me my Glock 34s are a bit more forgiving of a less than optimal grip than my 1911s. I think this is partly because I have a tendency to press the 1911 trigger a bit harder than is necessary and if my grip isn't right it affects my shots -- mostly I shoot low in that case. It's almost as if the combination of proper strong grip, isolating the trigger finger, and a good press are pretty much everything assuming decent sight alignment. :)

I know --- "well duh".

[psalms144.1]

I noticed this dramatically last week shooting my new M2.0 45 and my G19. Shot the 2.0 first for about 200 rounds, and, while my work wasn't the best, it was all centered on the target - shooting a combination of speed drills up close and longer range accuracy drills. Switched to my G19, and was IMMEDIATELY shooting left - fairly far left (more left than usual even for me). Said "WTF" to myself, and CRANKED down with my support hand, back to center. I'm not sure what this shows, except that with GLOCKs, I have to really crush the weak hand grip to keep things together...

[LSP552]

Until my recent Beretta affliction, SIG TDAs and Glocks were the pistols I used for the last 20 years or so. I have to grip harder and pay more attention to my grip with Glocks than I do with either SIGs or Berettas. I “think” it’s part Glock grip angle and trigger geometry. My TDA SIGs and Berettas also weigh more, so that could be a factor as well.

Edit to add: I’ve decided that my next Beretta will be a PX4CC with trigger job from LTT. That’s closer to Glock weight than my metal frame TDAs and will make an interesting comparison for grip sensitivity.

[willie]

A very long time ago I was reading the very brief blurb that Colt called instructions and included in the box with fixed sight revolvers. For example, for the right handed shooter who was hitting left of aim, Colt advised using thumb pressure against the frame to shift impact to the right. I forgot the rest of the instructions. But grip does affect poi. Routinely I hit left of poi with any handgun that I shoot, especially Glocks.

[Dismas316]

Attended a class this summer with Paul Sharpe and William April and the entire first day was about really gripping hard on the gun with both hands. The improvement for everyone was immediate and noticeable. There were no novice shooters in the class. It became extremely clear in shooting fast with accuracy.

I, like many others that have posted, that other platforms, (sig, etc) do seem to be more forgiving than glock when shooting with a less than strong grip, especially the weak hand. However, what I find with ANY platform, is that if I am shooting very fast, that same weaker grip shows the flaws very quickly in recoil control and accuracy, at least for me.

Now that I have been competing, the stronger grip has created for me a better habit fundamentally. Which is beginning to create better consistency when I compete. The glock angle I have found is actually perfectly designed when you grab a gun with your strong hand and with the slight tilt of your wrist (to conform to the glock grip angle) locks the gun in place much stronger than say a sig for me. Now when I shoot any of my other non glocks, it feels a bit weird not locking my wrist down due to the glock grip angle. Of course, this is what works for me, ymmv.

[Clusterfrack]

Free recoil affects POI in rifles and pistols, and will typically send the bullet high. In rifles, a heavier gun or a suppressor tends to reduce this. In pistols, a heavier gun reduces this a lot. Typically this is only a couple inches at 25 yds. But some guns seem more prone to stringing as a function of grip and stance. Gen 1 M&Ps are the best example of this. The barrel lockup was apparently not well designed.

I can hit 6” steel at 50 yds with a Shadow 2 gripped loosely. A G34 will send it over the top.

[DAVE_M]

Grip pressure is irrelevant to accuracy to a single round fired.
Grip pressure is relevant to holding the gun still.

Two things matter:
1) The sights are aligned on target.
2) The sights do not move when the trigger is being pressed.

Once the trigger is pressed, you do not physically have enough time to alter the direction of the firearm before the bullet exits the barrel. If your round did not go where it was intended to go, then it was moved prior to the primer being struck.

Grip pressure is entirely relevant to follow up shots.

[GJM]

For those that rely on a strong support hand grip to shoot the Glock, what happens when you shoot with just one hand?

[Clusterfrack]

For those that rely on a strong support hand grip to shoot the Glock, what happens when you shoot with just one hand?

POI will be slightly high and shifted toward the side you are holding (sights do not lift vertically). Tucking the elbow and blading a bit helps with the windage shift.

[LSP552]

Grip pressure is irrelevant to accuracy to a single round fired.
Grip pressure is relevant to holding the gun still.

Two things matter:
1) The sights are aligned on target.
2) The sights do not move when the trigger is being pressed.

Once the trigger is pressed, you do not physically have enough time to alter the direction of the firearm before the bullet exits the barrel. If your round did not go where it was intended to go, then it was moved prior to the primer being struck.

Grip pressure is entirely relevant to follow up shots.

I’d say that stronger grip pressure on a Glock helps ME manipulate the trigger with less chance of disturbing the sights.

[GJM]

I am out on the range now, and just shot a 25 yard Glock group, holding the pistol as lightly as I couldn’t and not have it fall out of my hands.

30517

[Clusterfrack]

Wow, good shooting dude! Maybe 2” high?

[Clusterfrack]

Pistols:
https://youtu.be/qm_xuzHHuG0

Rifles:
http://forum.snipershide.com/threads/the-effect-of-free-recoil-on-poi.63507/

http://forum.accurateshooter.com/threads/recoil-versus-poi.3808628/

[DAVE_M]

I’d say that stronger grip pressure on a Glock helps ME manipulate the trigger with less chance of disturbing the sights.

It can, and does for me also, but it's not a universal requirement.

[GJM]

Free recoil affects POI in rifles and pistols, and will typically send the bullet high. In rifles, a heavier gun or a suppressor tends to reduce this. In pistols, a heavier gun reduces this a lot. Typically this is only a couple inches at 25 yds. But some guns seem more prone to stringing as a function of grip and stance. Gen 1 M&Ps are the best example of this. The barrel lockup was apparently not well designed.

I can hit 6” steel at 50 yds with a Shadow 2 gripped loosely. A G34 will send it over the top.

With a 25 yard zero, I expect my 9mm pistols and slug guns to be several inches high at 50, back on at 75 yards and then dropping. Assuming a center hold on a six inch steel at 50, wouldn’t take much to go high?

[STI]

I'm much closer to a beginning pistol shooter than you guys in here - with that said:

When I got to learn from Gabe earlier this summer, he did two things with my grip. He had me take a little bit of the bottom of the heel of my right palm off the grip, in order to cement the whole left support hand palm onto the grip. Then, he had me "torque" my left hand up into the weapon light rail area.

This tightened up my groups and took them from consistent left or high left, to centered. I have adopted this for all my shooting and am learning to change my draw so that I get that grip by the time I'm extended.

These changes made several magnitudes more of a before/after difference than any changes I can make in grip pressure, two handed or single handed.

[DAVE_M]

With a 25 yard zero, I expect my 9mm pistols and slug guns to be several inches high at 50, back on at 75 yards and then dropping. Assuming a center hold on a six inch steel at 50, wouldn’t take much to go high?

A 25 yard zero with a 9mm pistol shouldn't put you several inches high at 50 yards. At most, it's an inch or two. Anymore than that is coming from you.

When is the last time you shot your gun from a rest to check zero at 25 yards?

[GJM]

A 25 yard zero with a 9mm pistol shouldn't put you several inches high at 50 yards. At most, it's an inch or two. Anymore than that is coming from you.

When is the last time you shot your gun from a rest to check zero at 25 yards?

What is the effect of the red dot/barrel offset on 50 yard trajectory?

I shoot groups all the time at 25 yards, but always freestyle since that is how I shoot the pistols in the field and competing.

[DAVE_M]

What is the effect of the red dot/barrel offset on 50 yard trajectory?

I shoot groups all the time at 25 yards, but always freestyle since that is how I shoot the pistols in the field and competing.

Using a 1” offset, 25 yard zero, and common 9mm ammo, it’s about a .8” drop. I don’t know of a single person that can shoot 1” groups at 50 yards though, even from a bench.

[GJM]

Using a 1” offset, 25 yard zero, and common 9mm ammo, it’s about a .8” drop. I don’t know of a single person that can shoot 1” groups at 50 yards though, even from a bench.

Just to clarify, the effect of the one inch offset is an additional .8 inch to the whatever higher POI that occurs at 50 yards with a 25 yard zero and iron sights.

Back to the original thought, I bet a bunch of PF dollars that most shooters (not Cluster) would think their bullet would impact lower at 50 yards not higher. With six inch steel at 50 yards, and a center hold, the bullets will strike the top of the steel without aiming errors. Either a red dot or Kentucky windage for “all that distance” will make it worse. An infomed shooter would likely hold on the lower part of a six inch plate at 50 yards.

[Clusterfrack]

Just to clarify, the effect of the one inch offset is an additional .8 inch to the whatever higher POI that occurs at 50 yards with a 25 yard zero and iron sights.

Back to the original thought, I bet a bunch of PF dollars that most shooters (not Cluster) would think their bullet would impact lower at 50 yards not higher. With six inch steel at 50 yards, and a center hold, the bullets will strike the top of the steel without aiming errors. Either a red dot or Kentucky windage for “all that distance” will make it worse. An infomed shooter would likely hold on the lower part of a six inch plate at 50 yards.

Agree.

Also, POI from a rest will often not be the POI offhand. Whether an inch or two at 25 is a big deal or not depends on what you need to shoot.

While we are on this topic, how you chamber the round can affect your POI too. (Press checkers take note).

[DAVE_M]

Just to clarify, the effect of the one inch offset is an additional .8 inch to the whatever higher POI that occurs at 50 yards with a 25 yard zero and iron sights.

Back to the original thought, I bet a bunch of PF dollars that most shooters (not Cluster) would think their bullet would impact lower at 50 yards not higher. With six inch steel at 50 yards, and a center hold, the bullets will strike the top of the steel without aiming errors. Either a red dot or Kentucky windage for “all that distance” will make it worse. An infomed shooter would likely hold on the lower part of a six inch plate at 50 yards.

What happens when someone shoots freestyle will not always yield the same result as the mechanical accuracy of a firearm.

Certain zeroes will require a hold under, some require a hold over, but 9mm trajectories do not drop several inches at 50 yards, nor should they be several inches above the POA with a 25 yard zero.

[STI]

how you chamber the round can affect your POI too. (Press checkers take note).

I've wondered about that. What's the preferred way to chamber from slide lock with full mag, slingshot or drop slide lock?

[DAVE_M]

Agree.

Also, POI from a rest will often not be the POI offhand. Whether an inch or two at 25 is a big deal or not depends on what you need to shoot.

While we are on this topic, how you chamber the round can affect your POI too. (Press checkers take note).

Can you provide quantifiable data on that?

[Clusterfrack]

I've wondered about that. What's the preferred way to chamber from slide lock with full mag, slingshot or drop slide lock?

Either as far as I know. But easing the slide forward or press checking changes the lockup and chambering of the case. In some cases this results in a significant poi shift.

[Clusterfrack]

Can you provide quantifiable data on that?

I’ll try to collect some next time I have a chance. I’d like to verify that too.

[Toonces]

Grip pressure is irrelevant to accuracy to a single round fired.

I wouldn't make an absolute statement to that effect. As soon as the bullet starts moving, the gun starts moving. Differences in grip strength will make differences in the angle of the barrel as the bullet leaves, which will determine where the bullet will impact relative to the sights. The differences are small compared to everything else that determines group placement, I'm not saying inches at 25 yards, but there is some effect. The more accurate the gun and accuracy intensive the task, the more often it will be seen. I've seen it in bullseye pistols and bench rest rifles. It's also why I want people to sight in their own rifles that will be used for big game hunting.

[GJM]

I’ll try to collect some next time I have a chance. I’d like to verify that too.

Some years back, I spent a fair amount of time shooting at 100 yards with a G3 Glock 17. There would consistently be one shot that was different than the rest of the group. Enough so, I experimented with shooting the first shot at a 50 yard steel, and then shot groups at 100. Posted on it, with pictures, here on the forum.

[DAVE_M]

I wouldn't make an absolute statement to that effect. As soon as the bullet starts moving, the gun starts moving. Differences in grip strength will make differences in the angle of the barrel as the bullet leaves, which will determine where the bullet will impact relative to the sights. The differences are small compared to everything else that determines group placement, I'm not saying inches at 25 yards, but there is some effect. The more accurate the gun and accuracy intensive the task, the more often it will be seen. I've seen it in bullseye pistols and bench rest rifles. It's also why I want people to sight in their own rifles that will be used for big game hunting.

So you’re saying you believe the gun can move from the time the primer is struck to the bullet exiting the barrel?

[Toonces]

So you’re saying you believe the gun can move from the time the primer is struck to the bullet exiting the barrel?

Absolutely.

[Clusterfrack]

Absolutely.

See video and links in my post above.

This is a big reason why shooting rifles from a stable prone or bench position is not as easy as just lining up the crosshairs.

[Jesting Devil]

Free recoil affects POI in rifles and pistols, and will typically send the bullet high. In rifles, a heavier gun or a suppressor tends to reduce this. In pistols, a heavier gun reduces this a lot. Typically this is only a couple inches at 25 yds. But some guns seem more prone to stringing as a function of grip and stance. Gen 1 M&Ps are the best example of this. The barrel lockup was apparently not well designed.

I can hit 6” steel at 50 yds with a Shadow 2 gripped loosely. A G34 will send it over the top.

That makes sense, especially as a light, compact .40 (G23) should be even more prone to the effect.



Grip pressure is irrelevant to accuracy to a single round fired.
Grip pressure is relevant to holding the gun still.

Two things matter:
1) The sights are aligned on target.
2) The sights do not move when the trigger is being pressed.

Once the trigger is pressed, you do not physically have enough time to alter the direction of the firearm before the bullet exits the barrel. If your round did not go where it was intended to go, then it was moved prior to the primer being struck.

Grip pressure is entirely relevant to follow up shots.

This is exactly what I thought previously and what I have taught in classes but I am no longer completely sure. I'm not ruling out poor trigger control (width of the group certainly indicates this) but the decided shift straight up when I called the shot fairly close to center was odd.

I'm going to grab some different rental guns to test this when I'm at the range this weekend, from heavy to light and different calibers. The lighter guns with the hottest rounds should show the biggest shift. I'll remember to get photos this time

[DAVE_M]

This is exactly what I thought previously and what I have taught in classes but I am no longer completely sure. I'm not ruling out poor trigger control (width of the group certainly indicates this) but the decided shift straight up when I called the shot fairly close to center was odd.

I'm going to grab some different rental guns to test this when I'm at the range this weekend, from heavy to light and different calibers. The lighter guns with the hottest rounds should show the biggest shift. I'll remember to get photos this time

I would love to see, under high speed video, the gun move AFTER the primer is struck (but before the bullet leaves the barrel). I’d be willing to bet it is so minuscule that the human eye cannot see it in real time, and the shooter moved the gun prior to pressing the trigger completely.

[Toonces]

I would love to see, under high speed video, the gun move AFTER the primer is struck (but before the bullet leaves the barrel). I’d be willing to bet it is so minuscule that the human eye cannot see it in real time, and the shooter moved the gun prior to pressing the trigger completely.

Guns absolutely move before the bullet leaves the barrel. It's Newton's 3rd Law. No one is saying the movement of the gun while the bullet is in the barrel is going to turn an X into a wide right miss or 7 (that's on the shooter). But how much the gun moves under recoil does affect the POI, how much depends on all the rest of the factors.

For example, movement of the gun while the bullet is in the barrel is why revolvers hit high with heavy, slow bullets. The slow bullet is in the barrel longer, allowing the gun more time to elevate in response to the recoil impulse. The increased elevation of the barrel overrides the external ballistics that will have the slower bullet drop more due to a longer flight time.

The most extreme example I've seen was my Ruger No. 1 in 45-70. A very hot load with a 250 grain Barnes X bullet at about 2800 fps hits over two feet low at 100 yards compared to a "normal" 350 grain Lead bullet. It was truly a WFT moment that had me checking my scope ring tightness, scope tracking, and ability to group on target with the normal load before I figured it out.

[DAVE_M]

Guns absolutely move before the bullet leaves the barrel. It's Newton's 3rd Law. No one is saying the movement of the gun while the bullet is in the barrel is going to turn an X into a wide right miss or 7 (that's on the shooter). But how much the gun moves under recoil does affect the POI, how much depends on all the rest of the factors.

For example, movement of the gun while the bullet is in the barrel is why revolvers hit high with heavy, slow bullets. The slow bullet is in the barrel longer, allowing the gun more time to elevate in response to the recoil impulse. The increased elevation of the barrel overrides the external ballistics that will have the slower bullet drop more due to a longer flight time.

The most extreme example I've seen was my Ruger No. 1 in 45-70. A very hot load with a 250 grain Barnes X bullet at about 2800 fps hits over two feet low at 100 yards compared to a "normal" 350 grain Lead bullet. It was truly a WFT moment that had me checking my scope ring tightness, scope tracking, and ability to group on target with the normal load before I figured it out.

I’m aware it moves. It’s negligible.

However, the original post I quoted said that lightweight guns cause the POI to be “several inches high.”

[Toonces]

I’m aware it moves. It’s negligible.

However, the original post I quoted said that lightweight guns cause the POI to be “several inches high.”

Minuscule and negligible really add up when shooting handguns at longer than the "normal" 7-10 yards. The OP shot a 3.5" five shot group at 25 yards. That's pretty damn good. I'm going to give him the benefit of the doubt based on that group size and say that he's doing a lot more right than wrong. Based on the description of the two groups, there was one group on top of the other, with the loose grip group higher (and wider). That makes perfect sense from a Physics standpoint. Is that the only reason?...don't know.

Just out of curiosity, do you train a lot of beginning handgun shooters?

[ASH556]

I've gone to post this 3 times and chickened out, but WTF, here goes:

In my journey to improve my accuracy/precision with a pistol, I spent a lot of time focused on 25yds. That was the beginning of my journey and helped me develop some solid habits. For instance, I posted a target last week of a 95/100 at 25 yds. First 10 rounds fired being 6 months cold on the pistol. It's not bragging, it's proper application of the fundamentals developed over the last several years.

I agree with whoever posted the bit about grip being the forgotten fundamental. Certain grip structures that work well for recoil mitigation will introduce forces into the pistol that show up as bad groups at distance unless you replicate your grip pressure 100% of the time all the time. I don't think that's realistic. Fatigue is real. So, I think it's important to create as neutral a grip as possible. Hold the pistol stable, but don't use a grip that induces massive left, right, up, or down forces unless you counter it with an opposing force; because you'll fatigue, the opposing force will cease to balance, and you'll start pushing or pulling shots left, right, up, or down.

Here's my "aha!" moment. In one day, with one grip shift, I was able to "neutralize" my grip and shrink my 25yd groups by an inch or two immediately. These targets were shot on the same day an hour apart. More about the journey published here if you care: https://pistol-forum.com/showthread.php?13149-The-choice-accuracy-vs-et-cetera/page7

8/30/14 4:28 pm:

http://i854.photobucket.com/albums/ab104/ASH556/671ECAB1-6EEA-4D5F-A392-DE776E09376B.jpg (http://s854.photobucket.com/user/ASH556/media/671ECAB1-6EEA-4D5F-A392-DE776E09376B.jpg.html)

8/30/14 5:33 pm:

http://i854.photobucket.com/albums/ab104/ASH556/4E58BC61-4B19-4D10-A06B-903BB90E4C5B.jpg (http://s854.photobucket.com/user/ASH556/media/4E58BC61-4B19-4D10-A06B-903BB90E4C5B.jpg.html)
http://i854.photobucket.com/albums/ab104/ASH556/449F4290-8DC2-4723-AEB2-A7ACF0653842.jpg (http://s854.photobucket.com/user/ASH556/media/449F4290-8DC2-4723-AEB2-A7ACF0653842.jpg.html)

Here's that 6 months cold target:

https://pistol-forum.com/attachment.php?attachmentid=30105&d=1536688943

[DAVE_M]

Minuscule and negligible really add up when shooting handguns at longer than the "normal" 7-10 yards. The OP shot a 3.5" five shot group at 25 yards. That's pretty damn good. I'm going to give him the benefit of the doubt based on that group size and say that he's doing a lot more right than wrong. Based on the description of the two groups, there was one group on top of the other, with the loose grip group higher (and wider). That makes perfect sense from a Physics standpoint. Is that the only reason?...don't know.

Just out of curiosity, do you train a lot of beginning handgun shooters?

You’re ignoring, or misunderstanding, the point. The claim was that a G34 with a loose grip sent rounds “several inches high,” while a steel framed gun did not. My argument is that it has nothing to do with the gun, and everything to do with the person pulling the trigger. To prove that, you can review high speed video and/or shoot from a rest and compared the results. Guns don’t become less accurate in freestyle shooting...

And no, I don’t have the time nor the patience to teach new shooters.

[JAD]

The only discernible impact I've found is that if I press a gun's trigger somewhat badly, a strong grip can somewhat neutralize the effect, which is normally lateral. I shoot Glocks left. I shoot Glocks less left when I grip them like they're trying to bite me.

It is not enough to deal with a truly terrible press, like I can perform on a P30 LEM.

It is unnecessary with a trigger which is suboptimal for threat management, e.g. a 1911. I hold those with Cooper's 'quail' grip and it works fine.

[Toonces]

You’re ignoring, or misunderstanding, the point. The claim was that a G34 with a loose grip sent rounds “several inches high,” while a steel framed gun did not.

I'm not ignoring anything intentionally. I did have some misunderstanding, as I took your first post (#12) to be directed to the OP, not Clusterfrack. With that in mind, I can easily see how there is a difference between a 26 oz gun (the 34 section of Glock's website is down, weight may not be 100% accurate) with a 5.31" barrel, and a 46.5 oz gun with a 4.89" barrel, both held loosely. Physics dictates that the heavier, shorter barrel gun is going to rotate less (ignoring weight distribution, bore height, etc...), therefore it's not going to shoot as high.


My argument is that it has nothing to do with the gun, and everything to do with the person pulling the trigger. To prove that, you can review high speed video and/or shoot from a rest and compared the results. Guns don’t become less accurate in freestyle shooting...

I would say it has something to do with the massive difference between the guns, and it might have something to do with the person pulling the trigger. I see things differently than your absolute statement quoted above. Also, many guns shoot to a different POI when rested as compared to freestyle due to how they move in recoil.


And no, I don’t have the time nor the patience to teach new shooters.

The reason I asked about training new shooters is I thought your statements sounded like things to tell someone in training who has never shot before. If they happen to get good enough to understand they are not 100% correct, they will understand why you said them. Until then, keep it simple.

Regardless, after rereading the thread, I still think you have factual errors in post #12 regarding grip pressure being irrelevant to accuracy and if the round doesn't go where intended - it's you. While they are good general guidelines, they are not absolutely true. I also don't think we're going to change the other's mind, and we'll agree to disagree.

[DAVE_M]

I'm not ignoring anything intentionally. I did have some misunderstanding, as I took your first post (#12) to be directed to the OP, not Clusterfrack. With that in mind, I can easily see how there is a difference between a 26 oz gun (the 34 section of Glock's website is down, weight may not be 100% accurate) with a 5.31" barrel, and a 46.5 oz gun with a 4.89" barrel, both held loosely. Physics dictates that the heavier, shorter barrel gun is going to rotate less (ignoring weight distribution, bore height, etc...), therefore it's not going to shoot as high.



I would say it has something to do with the massive difference between the guns, and it might have something to do with the person pulling the trigger. I see things differently than your absolute statement quoted above. Also, many guns shoot to a different POI when rested as compared to freestyle due to how they move in recoil.



The reason I asked about training new shooters is I thought your statements sounded like things to tell someone in training who has never shot before. If they happen to get good enough to understand they are not 100% correct, they will understand why you said them. Until then, keep it simple.

Regardless, after rereading the thread, I still think you have factual errors in post #12 regarding grip pressure being irrelevant to accuracy and if the round doesn't go where intended - it's you. While they are good general guidelines, they are not absolutely true. I also don't think we're going to change the other's mind, and we'll agree to disagree.

If there are factual errors, I would like to see the facts.

[Clusterfrack]

I’ll post some pistol data within a week. I’m glad to have a reason to quantify this.

Regarding rifles, it’s really not debatable that recoil control affects POI.

[scjbash]

Minuscule and negligible really add up when shooting handguns at longer than the "normal" 7-10 yards.

Very true. Some first gen M&P's with early unlocking issues were a perfect example of movement before the bullet leaves the gun. The POI shift between fast and slow bullets can be measured in inches at 25 yards with a stock barrel, and it's why the shift disappears with Apex barrels that produce a longer dwell time. I don't consider a difference of inches at 25 yards to be negligible.

[Robinson]

The only discernible impact I've found is that if I press a gun's trigger somewhat badly, a strong grip can somewhat neutralize the effect, which is normally lateral. I shoot Glocks left. I shoot Glocks less left when I grip them like they're trying to bite me.

It is not enough to deal with a truly terrible press, like I can perform on a P30 LEM.

It is unnecessary with a trigger which is suboptimal for threat management, e.g. a 1911. I hold those with Cooper's 'quail' grip and it works fine.

For me, and this is something I didn't anticipate happening back when, 9mm 1911s are less forgiving of improper grip than .45s. I'm relatively new to Glocks and I already shoot my G34s better than my 9mm 1911s. But I shoot my .45 1911s better than either. Weird. Counter-intuitive even. Something about the physics of it I haven't pinned down yet.

[JAD]

For me, and this is something I didn't anticipate happening back when, 9mm 1911s are less forgiving of improper grip than .45s. I'm relatively new to Glocks and I already shoot my G34s better than my 9mm 1911s. But I shoot my .45 1911s better than either. Weird. Counter-intuitive even. Something about the physics of it I haven't pinned down yet.

That's messed up man.

[Robinson]

That's messed up man.

I know. I'm pretty sure it's just me. You'd think the difference in recoil would make the 9mm 1911s much easier to shoot well. Hence folks referring to it as "cheat mode" right? Went to the range again today though, and my targets told the above tale.

What I should probably take away from this is that I need more practice with the 9mm 1911s. I have sort of been neglecting them for the G34s the last few months. The .45 thing might just be familiarity with its shooting characteristics from all the years I spent shooting and carrying them. I dunno.

[1slow]

Agree.

Also, POI from a rest will often not be the POI offhand. Whether an inch or two at 25 is a big deal or not depends on what you need to shoot.

While we are on this topic, how you chamber the round can affect your POI too. (Press checkers take note).


FAL rifle (tilting bolt ) shooters have sometimes noticed vertical changes in POI depending on how many rounds are in the magazine and how this affects spring tension pushing up on the bolt and thus affects bolt lockup.

In a Browning tilting barrel lock up, I would think how hard the slide closes could possibly affect barrel vs slide alignment and thus whether the bore aligned consistently with the sights.

[1slow]

IMHO guns , both pistol and rifle, that are light for their caliber, change POI more with variations in hold.

[Jesting Devil]

So I'm not sure this proves anything conclusively. Tested 3 guns and was planning to test 2 more but the lane I was using on my lunch break broke (yay indoor range). All guns are rentals, stock with stock sights and well worn by daily use. I shot 1/2 magazine through each with a loose grip followed by a solid, tight grip.

Guns tested: Sig P226 - 9mm, Glock 43 - 9mm, Sig 1911 - .45
Ammo: 9mm Blazer aluminum 115gr. FMJ .45 Winchester 230gr. FMJ
Target Photos: 1st - Loose grip 2nd - Firm grip

Results: I'm suspecting that my initial group shift was more a fluke of trigger control than one of recoil physics. I saw no evidence of a loose grip causing a shift in a particular direction although groupings were decidedly better when gripped firmly. I will test the original gun (Glock 23, NY trigger) again along with my tuned CZ SP01 later on for some final data points.

Added Notes: The 1911 had the best sights and trigger in my opinion and was the most confidence inspiring. The 226 choked hard every shot on the Blazer aluminum ammo when gripping loosely and 2 more when gripping harder. The G43 had no problem with it.

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[Clusterfrack]

Ok, I'm back from the range with a big mouth full of crow feathers. DAVE_M is correct. In a Gen 4 G34 with a KKM barrel, stabilized on a table, I cannot measure a POI shift between the following:
-Gripped tightly
-Gripped loosely
-Held just by the bottom of the grip so the gun flips a lot (this caused stovepipes and FTFs)

A tighter grip did cause the group to be tighter.

I also confirmed the same thing using a Shadow2.

I'm really glad to have cleared this up so I can stop passing on incorrect information.

Here is a 10 shot target from the G34 at 20 yds. 5 shots centered in the paster are gripped tightly. The more widely scattered hits are loosely gripped. Note that there are some doubles (2 shots one hole) on this target. The low one was a bad trigger press.
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I’ll post some pistol data within a week. I’m glad to have a reason to quantify this.

Regarding rifles, it’s really not debatable that recoil control affects POI.

[Toonces]

Ok, I'm back from the range with a big mouth full of crow feathers. @DAVE_M (https://pistol-forum.com/member.php?u=16404) is correct. In a Gen 4 G34 with a KKM barrel, stabilized on a table, I cannot measure a POI shift between the following:
-Gripped tightly
-Gripped loosely
-Held just by the bottom of the grip so the gun flips a lot (this caused stovepipes and FTFs)

A tighter grip did cause the group to be tighter.

I also confirmed the same thing using a Shadow2.

I'm really glad to have cleared this up so I can stop passing on incorrect information.

Here is a 10 shot target from the G34 at 20 yds. 5 shots centered in the paster are gripped tightly. The more widely scattered hits are loosely gripped. Note that there are some doubles (2 shots one hole) on this target. The low one was a bad trigger press.
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Interesting...did you do any testing at ranges longer than 20 yards? I’ll take some pistols and way more accurate than I am and test at 50 yards, Soon(tm). I’ll document with pics and report back. It it turns into a victory lap for DAVE_M I’ve got a minivan that seats eight and I’ll buy the first round.

(This post is the third attempt. I tried twice from my PC and was rejected by my antivirus. )

[Clusterfrack]

Interesting...did you do any testing at ranges longer than 20 yards? I’ll take some pistols and way more accurate than I am and test at 50 yards, Soon(tm). I’ll document with pics and report back. It it turns into a victory lap for DAVE_M I’ve got a minivan that seats eight and I’ll buy the first round.

(This post is the third attempt. I tried twice from my PC and was rejected by my antivirus. )

I thought carefully about what distance to use. I wanted a precise aiming point that couldn't be affected by lighting. These results are hard to reconcile with my past experience, but as they say the bullet doesn't lie. I still expect some guns will show a POI shift as a function of grip, but unless we have hard data...

[UNM1136]

I kinda stayed out of this, reading but not posting. It seems to me that a relaxed grip changes the basic trigger finger movent and the support for the platform as the trigger finger moves through the trigger press. I am not certain that a shooter setting up a high speed camera would necessarily be best positioned to capture those minute motions, particularly during the normal wobble during off hand shooting.

In Santa Fe, the DPS Academy has a magical camera system that attaches to the pistol and the head of the shooter, similar to what the demo guy with the AMU uses in his shot calling video elsewhere on the site. It shoots 60 frames per second, and records multiple points of view for diagnosing shooter errors. It seems to me that this would be ideal for this situation. But, 10 years ago it was a $120,000 gadget that apparently was on safari to photograph unicorns. I have heard its virtues, but never been allowed to see it in use.

Those skilled enough to call their shots at a high level and high volume would likely know when their shots were that far off, while those less skilled might not be fully aware of several inches at 50 yards.

I don't think I have an aswer, just a theory I will likely never be able to test.

pat

[Clusterfrack]

Here’s a link from a recent discussion on Enos Forum that confirms my understanding that recoil affects POI. It’s not a large effect, but measurable at distance. FYI Guy Neill is a USPSA shooter and had a career in ammunition manufacturing and testing.

https://forums.brianenos.com/topic/267350-strange-9-major-results/
Guy Neill:

“Slower bullets will be in the bore longer, allowing the muzzle to rise more before the bullet exits, resulting in higher impact point compared to the faster load. Not knowing the range, it's hard to say if the 1" difference is reasonable. For a 45 fps difference, it seems more than expected at handgun ranges.”

[LSP552]

Here’s a link from a recent discussion on Enos Forum that confirms my understanding that recoil affects POI. It’s not a large effect, but measurable at distance. FYI Guy Neill is a USPSA shooter and had a career in ammunition manufacturing and testing.

https://forums.brianenos.com/topic/267350-strange-9-major-results/
Guy Neill:

“Slower bullets will be in the bore longer, allowing the muzzle to rise more before the bullet exits, resulting in higher impact point compared to the faster load. Not knowing the range, it's hard to say if the 1" difference is reasonable. For a 45 fps difference, it seems more than expected at handgun ranges.”

My primary carry P226 has a 2” height difference between 124+P and 147 Gold Dots at 25 yards. The 124s are lower and the 147 zero perfectly. Gun has Trij HDs. My 239, zeros with the 124+Ps and shoot the 147s higher than I like. My 228 zeros with 147 and low with the 124+Ps (Sig X-Ray 8/8).

My Glocks shoot higher with 147 than 124 +P also. I’ve decided that keeping some different ammo is better than chasing sights across a bunch of different guns

[LSP552]

On grip pressure changing point of impact, and I agree that it does for me. This is more noticeable for me with Glocks. I really “believe” it’s more side pressure related but how do you prove that?

Perhaps a firmer grip just allows a better straight back trigger stroke and weight of the pistol is a bigger variable than pressure?

[Jay Cunningham]

If you don’t pre-tension (or “set”) your grip before you begin your trigger manipulation, it’s likely your hands will change their relationship to the pistol as you commence firing.

It’s important to use the same grip strength for short range aggressive shooting and long range precision shooting. It’s important to use the same grip strength for your dry practice as well.

[LSP552]

It’s important to use the same grip strength for short range aggressive shooting and long range precision shooting. It’s important to use the same grip strength for your dry practice as well.

This is something that I personally find easy to get lax on in dry fire, less so in live fire. When my attention starts to wander or my grip starts to slip, I call it a day.

[GJM]

This is something that I personally find easy to get lax on in dry fire, less so in live fire. When my attention starts to wander or my grip starts to slip, I call it a day.

It is extremely easy to get lax on grip pressure and trigger control dry firing, unless regularly validating with live fire.

[GJM]

While we all like advanced techniques, I would argue most of high level shooting is just the fundamentals of grip, stance and trigger control executed at a high level.

[LSP552]

While we all like advanced techniques, I would argue most of high level shooting is just the fundamentals of grip, stance and trigger control executed at a high level.

Completely agree, might add performed subconsciously.

[Jay Cunningham]

It’s what GJM said I think with “boring reliability” added in there.

Fundamentals executed with boring reliability.

[ASH556]

Like GJM said, flawless execution of the fundamentals trumps exotic strategies every time.

[Clusterfrack]

http://www.recoilweb.com/when-does-the-pistol-slide-start-to-move-127274.html