AR Sponsor
Posted: 11/11/2011 2:16:33 PM EDT
|
I'm sure this has been covered before, but nothing turned up in the search function.
I had a failure to feed today. It was maybe the second or third round in a 10 round mag. I pulled the trigger and nothing happened, so I put it on safe and dropped the mag. I could see that the bolt appeared to be closed. I pulled the charging handle back and ejected the round, which had a big scuff mark on it. I looked inside the rifle and everything seemed normal. I loaded the round that did not feed into another 10 round mag and it fed and fired fine. I then put the other mag back in and fired the rest of its rounds with no problems. This rifle has about 1200 rounds through it, and I have not had any problems with it. It is a S&W M&P 15 ORC. I think it's a mag issue, possible I didn't load it properly and it hung up in the mag. What typically causes ftf problems? Should I consider the offending mag suspect and destroy it? What is usually the cause of a ftf? |
| Never mind. If you put the safety on then it was cocked. It sounds like the bolt did not fully close. As you said, mag problem with the carrier loosing too much forward momentum stripping the round out of the mag and the bolt did not lock up fully even though it may have looked like it. Be glad it didn't fire. Try a new mag or polish the under side of the feed lips to remove the often found sharp edges. |
|
Quoted: I'd say around 90% of feed issues are mag related, when was the last time you pulled down your mags and cleaned/lubed them? +1 This is one good reason to keep a few pristine mags around that you ONLY use when you need to test a rifle with a known good mag.
|
| Those are good points. I haven't taken apart the mag that gave me the problem, I'll do that and give it a light lube. I'm also going to mark this mag so that I can keep track of it. I don't remember where I bought this mag from. My other 10 round mag is a c-products, and I have not had any issues with it. Unfortunately I'm limited to 10 round mags unless I buy preban. I also run my AR generously lubed, and my gas key is well staked so I'm pretty sure it didn't short stroke. |
|
Have yet to see a 10 round mag that feed correctly worth a dam without tweaking,
Start off by pulling the mag apart and cleaning it with CLP. Once back together, load two rounds in the mag, then push the back of the top round down into the mag , let it snap back up, push the front of the round down into the mag, then let it snap back up. Now on each time the round came back up, did the top round re-seat correctly against the bottom of the mag feed lips???? Now snap in a third round, and retest again. If the top round is not seating back up correctly (uniform against the bottom of the feed lip), then you need to tweak the mag spring to get the top round in the stack seating correctly |
AR Sponsor