Longer Barrels Exacerbate Pre-Ignition Push?

[Mark D]

After shooting G19s exclusively for a year, I recently started experimenting with G17. With the G17 I am much more likely to push shots low when shooting under a little bit of time pressure (e.g. The Test, 5 Yard Round Up, etc.).

I noticed something similar several years ago when transitioning from very short pistols (G26 and a Shield 1.0) to slightly bigger guns.

My hypothesis is that shorter barreled pistols are more forgiving of mistimed attempts to control recoil. The bullet leaves a shorter barrel slightly sooner than a comparable longer barrel, and there's less time for human error to force the bullet off target. It's a matter of micro-seconds, obviously, and an issue that can be addressed with training, but I think it's a thing.

I am prone to pre-ignition push, but generally minimize it's impact on my shooting with regular dummy and ball drills, skip loading, etc.

A disclaimer - there are minor differences in the triggers between my G19 and G17. The 19 has an Overwatch shoe and a minus connector. The 17 has an Apex kit. They're similar but are not identical. In the interest of experimentation, I will setup the trigger in the G17 the same as the G19 and do more testing. I'll post results here.

[LOKNLOD]

Is it possible that grip length and changes in how you’re imparting forces on the gun with a different grip and shape are as much or more an influence than barrel length? The hump on a 17 causes it to push in my hand a lot differently than a 19.

A G17 is 0.5” longer than a G19. At 1000ft/s, or 12000 in/s, a bullet is spending an extra 1/6000 of a second, ~0.00017 sec in the barrel. Thats not much time…

[WDR]

I'd also guess grip length and shape plays a larger factor between G26/19/17. Interested in others thoughts on this as well.

[Leroy]

I find longer sight radius guns easier to see sight misalignment during shooting and correct for it (easier to train and improve).

I have heard others talk about shooting shorter slide guns better (with iron sights), I rarely find this to be the case, and definitely not in the Glock lineup.

[mizer67]

I have not noticed this, in fact for me it'd be the opposite. If I'm shooting for max speed + accuracy on demand with the least likelihood to anticipate recoil, my order of preference would be something akin to:

G34>G17>G19>G43

The long slide and the mass thereof cycles slower, reduces felt recoil and provides more information when shooting irons.

I'd suspect two things are happening if shooting short slides and frames more accurately (with irons), both mental. One, there's less information coming from the sights, meaning there's less potential for one to snatch for a perfect sight picture and secondly there's less of a tendency to tighten your strong hand pinky finger and push shots right (or left) on a gun with a shortened grip, particularly one where you can't get a full hand on the gun.

From an objective data perspective, if I had to look back over the years at old USPSA production division stats of people shooting at a (very) high level, I don't think I'd find many short slide guns at the top of the list. Competitors being what they are, if a short slide offered even a small advantage, you'd see the equipment moving that way.

[JCN]

@Mark D I would probably flesh out your model.

There’s not time for the barrel length to make a meaningful contribution.

But muzzle weight x distance from the fulcrum and balance of the system can matter.

Very heavy dust covers / flashlights can weight the gun more towards the nose and with poor trigger follow through can cause a dip.

But here’s the flip side. More mass there if supported… helps prevent pre-ignition push.

So it comes down to shooter mainly.

The trigger and grip hump location in your situation are probably your main contributions.

You can test this yourself by later running a G45 versus a G47 type gun.

If you’re talking about tracking under recoil that’s a different thing. But the actual pre-ignition push for a trigger… barrel isn’t going to contribute as much as the grip hump location and the trigger weight.

IMO

[Clusterfrack]

Interesting idea. I don't think barrel length and ballistics enter into it for handguns. As @mizer67 wrote, the answer is often the opposite for most people. But why?

When the run recoils and lifts, the shooter has three options before firing the next shot:

1) Oppose recoil as it happens by pushing the gun down simultaneously as it fires. This pretty much universally accepted as a bad idea.
2) Let the gun rise, and return the gun later (as with bullseye shooting). This works well, but precludes splits faster than ~1s.
3) Push the gun back down immediately after it's fired. Because this happens faster than our nervous systems work, we have to time the recoil and send the signal to our muscles at just the right time. If that neural signal happens too early, it's a pre-ignition push.

For me, a heavier gun with a longer slide is easier to time, and requires less muscle to return. If I'm going to over-return or mis-time a gun, it will typically be a heavy caliber or a small light gun.

...My hypothesis is that shorter barreled pistols are more forgiving of mistimed attempts to control recoil. The bullet leaves a shorter barrel slightly sooner than a comparable longer barrel, and there's less time for human error to force the bullet off target...

I have not noticed this, in fact for me it'd be the opposite. If I'm shooting for max speed + accuracy on demand with the least likelihood to anticipate recoil, my order of preference would be something akin to:

G34>G17>G19>G43

The long slide and the mass thereof cycles slower, reduces felt recoil and provides more information when shooting irons.

I'd suspect two things are happening if shooting short slides and frames more accurately (with irons), both mental. One, there's less information coming from the sights, meaning there's less potential for one to snatch for a perfect sight picture and secondly there's less of a tendency to tighten your strong hand pinky finger and push shots right (or left) on a gun with a shortened grip, particularly one where you can't get a full hand on the gun.

From an objective data perspective, if I had to look back over the years at old USPSA production division stats of people shooting at a (very) high level, I don't think I'd find many short slide guns at the top of the list. Competitors being what they are, if a short slide offered even a small advantage, you'd see the equipment moving that way.

[feudist]

The longer sight radius may be giving you just enough extra information that your brain is attempting a finer alignment than your shot cycle normally accommodates. In turn this may lead to "stabbing "the trigger when the finer sight alignment presents.
IOW, you're not accepting the wobble as you normally do, and are trying to hit the perfect sight picture as it oscillates across the target and pull the trigger NOW!

[Archer1440]

Lock time has far more impact than ignition or barrel dwell time in terms of the human interface factor with any kind of shooting.

Hammer driven ignitions have longer lock times than striker ignitions, for example.

If you are already in motion as the hammer or striker drops, all else being equal, the striker gun will have an edge in accuracy. On paper.

However, in the real world, with modern firearms, dwell time is about 1/10th of lock time, and the two together are still about 100 times faster than any human reaction.

As a practical matter I would suggest learning to correctly shoot a smooth DA firearm- particularly a revolver. In my experience, that is a powerful tool for solving the sort of problem you describe.

[P30]

So it comes down to shooter mainly.

The trigger and grip hump location in your situation are probably your main contributions.

I agree in a way and suppose that it's a psychological reason. The G17 has a longer sight radius than the G19. So the G17 makes differences from a perfect sight alignment more visible. Then with a G17, some shooters want to aim too well. And when they finally achieve the perfect sight alignment, they pull the trigger too fast and significantly destroy perfection relatively long before ignition. The fraction of a millisecond the bullet stays in the barrel post-ignition does not cause the problem.

Remedy according to this hypothesis: Accept a non-perfect sight picture according to the distance and size of the target. You only need a good enough sight picture.