Never really posted an image of a build before so I hope this works. I've been chronicling the build over at my site. The stats:
J&T 16 inch upper in 7.62X39
YHM Flip up rear site
Some non-franken mags, which work very well now that my gunsmith showed me how to tweak them a bit.
Took Mr. Blasty to the range this weekend and had a problem. The problem was not with Mr. Blasty, but rather the ammo. Some Wolf ammo has recessed primers. With the Russian ammo, it’s hit or miss. Some of the primers are flush and most are not. The firing pin of an AR15 only pushes through a little bit (we’re talking thousandths of an inch, according to my gun smith). Hence, the firing pin should have no problem striking the primer of non-recessed primers. The solution is to buy ammo without recessed primers, and that may be difficult in 7.62X39. It’s nearly impossible to do if you want to buy Russian milsurp, like I do.
The trouble with buying good ammo is that you limit yourself to a few brands and they are pricey. Additionally, I already bought 1,000 rounds of 7.62. This brings us to plan B. Plan B initially involved getting my hands on a longer firing pin (you know, so it could poke through farther and strike the primer). However, due to mass production, the assembly line and other evils of capitalism, firing pins only seem to come in one size. Now, we have Plan C. Plan C involves shaving a little metal off the rear of the bolt carrier which will cause the firing pin to come forward a bit further. This will allow the pin to strike the recessed and non-recessed types of ammo. Should solve the problem, I’ll let you know how it goes.
The six rounds I managed to get off today did quite well. The magazines fed fine and no real problems. However, due to the primer issue, I had to go through about 60 rounds to get six to go off. This was annoying. Bang, click, rack, click, rack, click, rack, click. etc., etc. Oh well. Live and learn. Additionally, the Yankee Hill rear sight I got was dead center without any adjustment.
This problem, it would seem to me, would be common in most 7.62X39 builds. People have asked me to keep them updated as to how this little project goes and whether or not I would recommend it. Given this problem and the potential magazine problem (there are a lot of junk 7.62 mags out there that don’t feed right, though production of new ones will start soon and this will remedy that. The feed problem can usually be fixed by taking vice grips to the feed lips), my recommendation on this project is as follows:
1) If you want to buy a stock gun and shoot it out of the box with no tinkering, do not take on this project.
2) If you, like me, like to piddle with stuff, tinker with gizmos, tweak things, generally poke things with a stick, and have the time and energy to do it, then go ahead and give it a shot.
And I have since figured out not to buy wolf ammo.
Took him to the smith and he modified the bolt by sanding it down a bit and it works like a charm.
It sounds like you have something out of spec, get one of those fireing pin protrusion gauges.