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Posted: 5/2/2008 2:22:10 PM EDT
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I just got one of their 762x39 kits and out of the first 10 shoots 3 went bang and then only after I had put them in the second time (4th, 6th, 7th). The primers all have what looks like a deep enough dent, but no bang. I have tried the "take .010 off the bolt" and "take .007 off the firing pin" and still no bang. I swoped the firing pin from a .556 AR and no joy. HELP!! |
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Nope, not the ammo. It's the firing pin protrusion out of the bolt face. The problem is well documented here on AR15.com. Corrected mine by taking a couple thousands off the back of the bolt tail. There is also an AR15.com member who sells an upgraded bolt assembly that corrects this problem. I bet if you run domestic ammo like Win or Rem it will function just fine. IM me if you need specifics C1 ETA: My upper was a model 1 also, when I talked with them, they seemed clueless. |
Bullshit. The bullet doesn't know if it's in a AK47 or AR15. The major drawback for use of 7.62x39 in an AR15 is and always been the mags. There are a couple military grades of ammo that ignite regularily so mods to the bolt are recommended or use softer primer ammo. |
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I had the same problem. The following steps will do the trick: 1. Chamfer the firing pin hole at back of bolt 1/64 of an inch. 2. Put a light lapping compound( like Flitz ) on the length of firing pin, insert firing pin in bolt and use a drill at slow speed for 30 seconds. Remove firing, clean bolt and pin. Repeat step 2 three times. 3. Remove the the extractor and ejector. use 1/4" hard wood peg with a light lapping compound to polish the bolt face and side to remove tool marks. 4. Install an XP hammer spring and an XP buffer spring I used Wolff Springs. Oh yes if you removed .007 from your firing pin, you'll need a new one. The only other problem was with feeding Wolf 154 soft point ammo. To fix this I just polished the feed ramps into the chamber. I tryed different US and NON-US ammo and all ran well. Good luck, if you need more info IM me. Mike |
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I had some Wolf 123gr fmj that ran well with gun rigth out of the box, the ones with inset primers are the ones that failed to fire. I use a 10 round Cproduce mag and it works great. I like the Wolf ammo for practice and zeroing the sights and it's cheap. IMHO. Mike |
I call BullShit also..I have had ZERO problems out of my Model 1 Sales 7.63x39 upper. |
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Well it looks like I did it to myself, as I was putting the kit together I lost the 2 little F%^&ing pins, so I put the upper on another lower I have and it has the 15 minute trigger job. I finally got the kit lower together with a normal trigger spring and it went bang twice in the back yard. Tomorrow to the range. |
I say Bullshit too. My DPMS 7.62x39 runs great with DPMS frankenmags. So does my Colt. |
Where did you remove material? The bolt is easier to modify...... After making the proper mod, check the firing pin protrusion on the bolt face. |
| Ok, Ok, I made a mistake, I had clipped the hammer spring, not the trigger spring. But the other thing I had to do was open up the area around where the sear spring goes in the back of the trigger assembly because the sear spring would not colapse enough to get the trigger pin in. Just a little with the dremal. |
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