Accuracy question with hand cycled cartridge

[GJM]

This afternoon, I decided to shoot some off hand groups at 25 yards with the Gen 3 Glock 34 I was shooting. Taran sights, 13 pound recoil spring, OEM barrel.

Seemed like I was shooting decent groups, but with one flyer in each group:





Then, I started reflecting on my 100 yard groups with a Glock 17, where I would have four very good shots and one flyer. I decided to load six cartridges, fire one cartridge at steel, and then shoot the group. Here are the two groups I then shot:





I am starting to think that the first shot fired, after hand cycling the cartridge, hits to a different POI than the cartridges fired with the gun cycled by the firing process. Thoughts?

[Chuck Haggard]

I've seen that in other guns as well.

[Totem Polar]

Ayoob has written about this a fair amount. I've found it to be true, to greater or lesser extents, in some of my pistols.

[Casual Friday]

What you call a 25 yard flyer, I call serious bidness with a pistol. All joking aside, I've never thought this could even be a problem. I'm going to conduct my own study on this. Probably not at 25 though, maybe 10.

[Lester Polfus]

What you call a 25 yard flyer, I call serious bidness with a pistol. All joking aside, I've never thought this could even be a problem. I'm going to conduct my own study on this. Probably not at 25 though, maybe 10.

You probably won't see it at ten, but you might.

My old Gen 3 Glock 34 did the exact same thing. It was less pronounced when I dropped the slide using the lever, as opposed to slingshotting it.

[Casual Friday]

What causes it?

[JohnO]

\ It was less pronounced when I dropped the slide using the lever, as opposed to slingshotting it.

How the round is manually cycled into the chamber can be key. I like to insert the mag and power stroke the slide, trying to duplicate the same slide action that occurs during firing.

I'm sure some pistols are more susceptible to this phenomenon than others.

[rsa-otc]

This is a known phenomenon with some semiautomatic pistols. Some folks have had some success sending their guns back to the factory to eliminate the problem. Others have some success eliminating the issue by vigorously working the slide. It seems to have something to do with how the barrel and slide come together when you manually load the first round compared to the normal slide function.

If you seem to have this problem I wouldn't do a press check after dropping the slide with a power stroke since that will disturb the barrel slide orientation. I drop the magazine and check to make sure a round was loaded or better yet check the loaded chamber indicator since dropping the magazine can disturb how the next round is presented to the chamber.

[ToddG]

As others have said, it's a known (or at least assumed) problem in some guns. It's unclear to me whether it's been noted because it's actually happening or because it's a good excuse for a 1-in-5 flinch/flyer. Having said that, when I shoot for accuracy measurements I almost always launch the hand chambered round downrange and keep the gun hot until the testing is over.

If you have the ability, I'd set up spotting scope for your wife (or a friend) to see if it's definitely the first round of each group. I'd purposely load 5rd mags so you're shooting a hand cycled round each time. Then if you want to get really complicated, you could load 2rd mags and see if the hand cycled round ended up as a "flyer" each time or at least a significantly greater percentage of the time than with the gun cycled rounds.

The theory has always been that the gun isn't locked up the same way when hand cycled as it is when manually cycled. I'm not quite sure that there's a lot of logic behind that but I'm not an engineer. FWIW, both Beretta and SIG did their accuracy testing with a hand cycled round.

[CCT125US]

When group shooting at 25 or 50 yds, I use a spotting scope or binos most of the time. I like to mentally tie the feel of the gun with the POI. I have not experienced flyers from the first round. I do typically have the gun at slidelock, and then rip the slide to the rear. Any flyers are due to my inability to keep the sights on target.