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View Full Version : Ever fix first shot flyers?


74Rallye
08-18-2015, 6:07 AM
I have an AR that's fired maybe 200 rounds. I changed the carbine buffer out for an H2 buffer and now I'm getting a flyer from the first shot out of the mag.
I was loading 5 rounds at a time and the first shot was out about 8 inches in the 2 o'clock position. This happened with the first 2 groups of 5 using different types of ammo as well. After that there were no more flyers that day. I've read that this is likely caused by the difference in the way the bolt seats when chambering a round by hand vs. the semi-auto chambering of a round. I'm going to try putting the carbine buffer back and see if that's the cause.
Are there any other possible causes I should look for?

seasnake
08-18-2015, 6:52 AM
Is your optic loose ?

rero360
08-18-2015, 7:07 AM
This is a well known issue, happens to garands as well I'm told. I was told about an article talking about it but I never did find it.

I've never experienced this issue first hand, perhaps its because I always use the bolt release on fresh mags and never load from a closed bolt, or I just have never noticed it at the closer ranges where I record my hits with better accuracy.

I've thought about it from a purely mechanical point of view and I have failed so far to see how it can happen, so I'm inclined at this point to believe its a shooter issue and not equipment issue. But I could be wrong.

redpyro911
08-18-2015, 7:17 AM
Some semi-auto pistols have a similar issue when the first round is fired from a magazine after reloading and closing the slide using the slide release. Something to do with the cartridge seating differently in the chamber when the slide is released forward manually. After the first shot the slide is cycled by recoil, and groups tighten.

musketjon
08-18-2015, 12:08 PM
M1's are notorious for this. It's just the nature of the beast, however, with bedding and parts hand selection, the effects can be minimized.
Jon

wweigle
08-18-2015, 9:14 PM
I would try racking that first round in as violently as a fired subsequent round. Might help the bolt and round settle in battery in a similar position as a second round would. Seems logical to me.

musketjon
08-19-2015, 7:43 AM
I would try racking that first round in as violently as a fired subsequent round. Might help the bolt and round settle in battery in a similar position as a second round would. Seems logical to me.

It is a physical impossibility to replicate the self loading function when manually operating the rifle no matter how roughly you handle it.
Jon

Flux Capacitor
08-19-2015, 8:00 AM
Drop an open bolt on a new mag.

rero360
08-19-2015, 9:36 AM
It is a physical impossibility to replicate the self loading function when manually operating the rifle no matter how roughly you handle it.
Jon

True as you will likely never be fast enough to get the charging handle back in the locked position without the Gas Key riding against it.

Now from a purely mechanical perspective, one could calculate how far back the BCG travels before starting its return to battery. I would imagine it would be slightly further back than where it rests against the bolt stop, otherwise you would suffer from failure to lock back. How much further it travels, I don't know, and I'm sure it probably varies between ammo types.

If one knew that distance, then the calculations can be made showing how much force the bolt chambers a round with, verses starting from an open bolt and hitting the bolt release, with using the charging handle being less and not nearly as consistent of a number as human variance enters into the calculations. Once these numbers have been calculated, you could see if there is enough of a difference to justify the first round flyer issue.

SonofWWIIDI
08-19-2015, 9:42 AM
Just aim your first shot 8" toward 8 o'clock position.

:hide:

itisagoodname
08-19-2015, 10:07 AM
Does the rifle have feed ramps? Are they lined up? Does the upper reciever have machined feed ramps that match the chamber?

http://i3.photobucket.com/albums/y95/jerrellwise/Gun%20Pics/feed_ramps2.jpg
http://i51.tinypic.com/r1arva.jpg

74Rallye
08-20-2015, 9:54 AM
I'm shooting with open sights off hand and it has A4 feed ramps.

I think I've found the problem! I took my Ruger 556 apart last night and looked it over closely. The bolt looked dry and the bolt didn't rotated smoothly. I cleaned and lubed it and it feels much better. It'll be a few days before I can test it.
I mentioned that it had about 200 rounds through it, but recalling all of the different brands of ammo I've tried, I think it's closer to 500 and this was the first time the bolt was disassembled since the initial cleaning when it was new. I tried every type and brand of ammo I could find in stores and at gun shows to see what it liked best. FWIW the PMC X-TAC 62 gn. is the favorite economy ammo so far, as I'm not shooting the $1 a round stuff.

BrassCase
08-20-2015, 11:49 AM
I'm shooting with open sights off hand and it has A4 feed ramps.

I think I've found the problem! I took my Ruger 556 apart last night and looked it over closely. The bolt looked dry and the bolt didn't rotated smoothly. I cleaned and lubed it and it feels much better. It'll be a few days before I can test it.
I mentioned that it had about 200 rounds through it, but recalling all of the different brands of ammo I've tried, I think it's closer to 500 and this was the first time the bolt was disassembled since the initial cleaning when it was new. I tried every type and brand of ammo I could find in stores and at gun shows to see what it liked best. FWIW the PMC X-TAC 62 gn. is the favorite economy ammo so far, as I'm not shooting the $1 a round stuff.

With AR15's you really have to pay attention to the condition of the BCG. If I was going to carry a spare part for an AR with me it would be a bolt.