1st shot POI different than rest

[bullockcm 0]

I bought a .223 a month ago to go with the x39 I have had for a couple of years. I ran about 60 rounds through it to make sure it functioned and then converted it. The gun functions fine however, the 1st round chambered manually shoots to a completely different POI compared to the rest of the rounds. When I did the conversion I added a Blackjack buffer, with the buffer installed the POI would be 2 - 4 inches high at 25 yards. Knowing the buffer isn't a big deal on the .223 and thinking it might be the problem I removed it and did more shooting. Now the 1st shot is 2 - 3 inches low compared to the rest. I have cleaned the gun and lubed it up, the other 9 shots can be covered by a quarter at 25 yards so the gun is shooting okay.

 

Is there anything I can do? Is it maybe a breakin issue and will get better with time? Thanks, Mitch.

[ironhead7544 35]

A lot of guns do this. Oil in the clean bore could cause it. Also when the barrel heats up, POI can change.

[bullockcm 0]

I don't think it is oil in the clean bore since it will do it after multiple magazine have been fired. I also don't think it is the barrel heating up in this case since I can shoot the first one then a couple more, drop the mag, shoot, insert mag, chamber a round manually and have the POI be the same as the very first round.

 

Seems to me this is related to the difference between chambering the round manually and the gun doing so automatically. I guessing I am wondering if the action will "free" up some or if there is something I can do to improve this.

[craig110 0]

Could you be initially holding the gun slightly differently than where the gun "settles in" during its normal recoil? I'd suggest trying a string of 10 shots like this:

 

- Put in the clip and manually chamber it. Shoot three bullets.

 

- Get well out of firing position for 10 seconds or so. *Be careful as you still have a chambered round.* (The barrel shouldn't substantially cool during this quick period.) Reshoulder the weapon and shoot three bullets.

 

- Repeat the second step, but fire off the remaining four bullets.

 

If you have only one bullet off by a few inches, then it points more to the manual chambering. If you have three bullets that are off by a few inches, then it could be related to how you hold the weapon before the first shot.

 

Craig

[Vermiform 26]

Probably doesn't matter but:

 

When you are manually chambering that first round, are you "babying" that round in, or are you pulling the charging handle back all the way and letting go of it? Might make a difference if manual chambering is the issue.

[bullockcm 0]

When I manually chamber a round I always let the bolt "fly" forward. Next time I have a chance to shoot I will try the body position test and also try manually chambering more rounds than just the first. Thanks for the help.

[craig110 0]

When I manually chamber a round I always let the bolt "fly" forward. Next time I have a chance to shoot I will try the body position test and also try manually chambering more rounds than just the first. Thanks for the help.

 

Let us know the results, ok? Thanks.

[5thShock 0]

There is a video on the net that shows an AK firing, slow motion with the dust cover off. I remember thinking when I saw it that it looked as though the bolt carrier was not quite hitting the rear trunnion. Could it be that manual cycling by pulling the bolt carrier ALL the way back is actually chambering the round with a bit MORE force than subsequent rounds?