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Posted: 2/9/2015 12:34:54 PM EDT
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I was working up some loads this weekend with reloads. I fired about 60 rounds broken down into about 12 five round groups loaded into a 20 round magazine. On three occasions, on the first round, I got a "click." After waiting a while, I dropped the magazine and cycled the bolt using the charging handle. It took considerable force to eject the round, but nothing crazy. None of the three primers had any marks on them. All three rounds fired fine on the second go round. These were the only malfunctions. One one occasion the rifle was charged from the handle, on the other two it was charged using the bolt catch.
I built the rifle myself. The barrel and and bolt carrier group are both from the same good-quality maker. The bolt was headspace checked by the maker to this barrel. The trigger is a Geissele G2S. The magazine was a 20 round Tango Down with five rounds loaded into it. I do not recall this malfunction happening before. I estimate the rifle has 750-1,000 rounds through it, all fired from the same magazine. Does anyone have any thoughts about what the cause of this malfunction might be? My guess is it's magazine-related, but that's just a guess. |
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Are you saying that on one of the failure to fires you closed the bolt by releasing the CH and on the other two you released the bolt catch?
The first thing that jumps out at me was that the bolt wasn't fully closed, especially with no witness marks on the primer (since just closing the bolt on a round will result in a small dimple) but the methods you described should have resulted in the bolt going home. |
| Obviously something is binding, check the extractor, check inside the extension and clean using a brush made for the purpose. Look for any unusual wear. Release the bolt on the first round, try the forward assist to determine if the carrier advances. Purchase a few dummy rounds and cycle the weapon a few times. At the point when the charge handle required extra force that's a red flag and time to call it a day. Have a qualified gunsmith locate the problem providing you cannot. |
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Quoted:
You are having a problem with some reloads that apparently don’t fully chamber and are then hard to extract? This is in a weapon that has had several hundred rounds through it. The reloads would seem to be at the top of the list. Do you think it was just coincidence that the problem occurred only on the first round of the magazine all three times? But for the problem only occurring with the first round, I agree with you completely. In total, 5% of the rounds (3 out of 60) had the problem. I'm not exactly sure how to do the math, but the odds of a strictly reloading-related problem turning up in the first round of 12 magazine loadings three times are remote. I think the odds of that are .0125%. |
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My take is the first chambered round in a mag is more likely to have problems in a marginal situation, so no I doubt it was a coincidence.
I take multiple mags and factory ammo to the range with me so if needed I have the ability to troubleshoot problems. Going strictly by what you posted my first choice would be ammo, but it would hardly be the only possibility. YMMV |
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Quoted:
Sounds more like your brass might not have been properly re-sized. I think you and PFC are on it. It's probably some slightly oversized brass combined with some unknown variable with the first round that exacerbates the sizing problem. Thanks for the help and feedback. |
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Most of my FTFeed or FTFire with reloads are on the first round stripped from the magazine using the charging handle.
Set the resize die so it cams over in the press or switch to a small base die.You will encounter a different set of issues with the small base die BTW. Your cases may just stick in the die before they can make it to the rifle. 
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Speaking of unknown variables there are several possibilities that may be contributing to the problem.
Light lube, weak action spring, magazine, headspace, etc. Headspace can have a telling affect. You posted the manufacturer checked it, but did you realize some manufacturers like it really tight? As in may fail a Go gage tight. This is normally no big deal function wise for most factory ammo, but may be a problem for a reloader. |
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