Help diagnose an odd handgun accuracy result

[matts2k]

I have a few variants of (essentially) the same pistol in different lengths, and I'm seeing odd results.

When I shot a 4.5" XDm and a 5.25" XDm back-to-back, I was substantially more accurate with the 4.5" than the 5.25".

I had the same result when I shot the CZ P07 and P09 back-to-back -- substantially more accurate with the P07 than the P09.

This goes against everything I believe SHOULD happen when I shoot a heavier firearm, with a longer sight radius.

To further complicate my diagnosis, I have shot the 4" and 5" PPQs, with no discernible difference in accuracy.

Please speculate what I might be doing wrong, or any other theories you might have.

Thanks!

[mrfat]

We'd need to see some targets to get a better idea. Maybe you break your wrists or do something else that causes instability. With longer barrels the movement is exaggerated and causes them to be less accurate?

[tbc]

Help diagnose an odd handgun accuracy result

^^^ yup


My theory:

Your muzzle changed direction right after pressing the trigger. The longer the slide, the further the POI from the POA.

You didn't experience the same on your PPQs is because the trigger is light and is a lot easier to control. The muzzles from both of your PPQs didn't change much after pressing the trigger.

[matts2k]

@tbc - clever thought - seems to fit the data. makes me think i need to send my 5.25 xdm & p09 for trigger work

or more dry-fire practice

or both

[tbc]

I am always a proponent of dry fire practice. I'd give it a try. It cost me $0.00

[Tok36]

^^^ yup


My theory:

Your muzzle changed direction right after pressing the trigger. The longer the slide, the further the POI from the POA.

You didn't experience the same on your PPQs is because the trigger is light and is a lot easier to control. The muzzles from both of your PPQs didn't change much after pressing the trigger.

Makes sense. The heavier pistol can also be harder to stay on target with after you have been shooting a bit. I noticed last range trip that when im tired my CZ75 SP-01 is harder to stay on target with than my CZ75 due to its weight. Keep in mind though i am still a nube

[Matt P]

The barrel length difference would not play a role.
Which one have you shot more?
Most firearms will see an improvement of greater accuracy through use. Trigger components meshing together and becoming smoother.
Beyond that, there are not many firearm owners who can obtain more accuracy than what the handgun is capable for.
For the majority of handgun owners, your ability or lack of it plays an massive role. Way outweighing other elements.
Are these both the same caliber and using the same ammo each?
Are the sights the exact same?
Are you shooting one and than immediately shooting the other? Is this an definitive test of each ones accuracy through resting the handgun for greater stability?
There are many factors that can affect the results beyond just which handgun is in your hand.
What you are experiencing is of no surprise to me.
The barrel difference is too small of one along with the weight. You simply input less in-accuracy with the shorter one versus the longer.

[David Mc]

For some odd reason I remember everyone saying the 5.25 is just as heavy as the 4.5 if not a tiny bit lighter. Correct me if in wrong. And try the thinnest Dawson front fiber sight, worked great for me. The shift situation with the 5.25 means nothing since the sights are fully adjustable.

[bulletblood]

Maybe with a long barrel the bullet is in the barrel too long, where the barrel has already unlocked and is beginning to tilt while the bullet hasn't exited yet. That would definitely affect accuracy.

[JTROKS]

I have a G23 and G27 and the G27 shoots more accurately than the G23. I think the G27 is more accurate with the loads I shoot through them. I'm gonna try some 165 grn JHP next time and see if the result are the same.

I also have a G35 and it's more accurate than the 23 and 27. It's not the length, some guns are just more accurate with a given load or tighter tolerance in mechanical fit makes it more accurate. Let's say your 5.25 has a looser bore and the mechanical fit in the lock up areas are not as tight as the shorter barreled gun. Guns vary in tolerances.