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Posted: 5/21/2008 4:47:16 AM EDT
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I just finished building an AR15 using a Model 1 upper, and the gun appears to be bending the round. Has anyone ever seen this before, and what could be causing it. It headspaces fine, and seems to cycle fine, but if you load a round and then eject the unfired case, the round is bent. Thanks |
| I don't have a camera available to post pictures, but it is getting bent on the neck down area. When you pull the round out and roll it on a table the bullet has a great deal of run out at the tip and there is a crease in the side of the case where the neck down starts on the main body diameter. |
| Don't fire your weapon until you work this out. Photos would be nice. Check the a round before you load it to make sure it not damage to begin with. Load it slowly to see if it binding. Did you have to use your forword assist to seat the rounds before? Try a different mag. |
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too late on the don't fire it thing. it seems to fire fine, but you can tell when a round was bent even after firing. the pressure fire forms the case to the chamber, but the rub mark on the shoulder is still evident. i worked the action by hand, and i can't see how this is happening. the case head seems to leave the feed lips way before the geometry seems like it would bend the case. the rub mark also does not appear to be cased by the barrel extension since the rub mark is wider than one of the lugs - you would see the lugs imprint on the case. this is a 5.56 rifle, but is it possible that the case is getting caught on the ejector when it gets free of the mag feed lips? my .458 and 7.62x39 uppers have a bevel cut into the side of the ejector for this reason. i'm using C-Products mags (they came with the rifle). |
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