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Posted: 4/19/2005 4:38:22 PM EDT
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Ok I went out this weekend and I had a problem. My bushmaster for the first time began to jam. I figured out what was happening but don’t know why all of a sudden this is occurring. For some reason the mags are now able to tilt in the mag well just enough to hook the B/C or allow the tip of the round to stop on the back of the chamber just below the feed ramps. This is happening on several of my mags that have been reliable to date. Twice on the second round attempted to be fired out of a full mag, Then several times In the middle of a full mag. If I push forward on the bottom rear of the mag the bolt will then release and chamber the round. What may have caused this to happen! I had some extra cash and ordered Magpul followers and Magpul’s for all my mags. I have 13 30 round mags over all. 6 are Bushmaster 4 are Center industries and the remaining 3 are unmarked gun show cheapies but have never caused a problem. My 3 oldest mags (Bushmasters) have been fitted with Magpul gear for months and until now never caused a jam. I installed Magpul gear on the remaining mags before I went shooting this weekend. I was using the same Ammo I have been shooting for a while Now, bulk 55gr Mil Surp. I clean the weapon after each and every time I shoot. The gun is still relatively new and has only had 2K rounds through it. I have not altered or added anything to this rifle other than an Accu-wedge. Things I did: I inspected the magwell for debris, flaws, or any damage or deformation. Found none that my eyes could see. I adjusted my mag catch in and out to see if it would hold the mag tighter in place this did not help. What does help is if I put forward pressure on the bottom back of the mag. The Bolt and Carrier look ok to my eye. So I do not know what to think. Is it the extra weight of the new followers in combination with the Magpul’s that is the problem? Lost and looking for a solution. Thanks to all in advance for your help. |
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| I recently had a similar problem with bullets stopping just below the feed ramps. I was functioning some 30 rnd mags that i pulled from a stash that usually just sit in a box. But also happened in a couple with crome silicon springs and magpul followers that i have used many times with no problem. i was shooting wolf 55 and 62 grain bullets mixed in. It semmed to happen half way through the mag. Later at home, iwas able to duplicate the problem. I checked the mag catch and that was okay. checking other mags showed that some had more front to back play than others. If i held forward pressure on the mags they would work ok. I dug up some brass screws about a half inch thick filed them down and made like an insert that would snap in under the trigger gaurd, leaving a little protruding into the magwell. In effect they tighten up the magwell. I have'nt shot it yet, but it works manually. |
| i recently had the same problem with my brand new carbon 15. first time on the range it jammed more then it fired. call bushy and they told me about the feed ramp issues they are having. sent the upper back to them today for a tune-up and some adjustments they say will fix the issue. i'll let you know next week when i get the upper back and try it out, if it fixed the feeding issue. |
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Tweak The very first time I took the rifle out I had two jams where the B/C slid over the round instead of extracting it out of the mag. And I also had two failure to fires because the bolt did not completely close on the round and I had to use the forward assist. The gun was brand new and I had only shot about 250 rounds that day. When I got home that evening I took apart the mag and cleaned it and gave it a light coat of CLP. Though I did clean the rifle before I took it out the first time I did not clean the mag. In any case since the first time out I have bought an additional 11 30 round mags 3 20 rounders and a 10 round and have nearly 2200 rounds down range without a hitch. So in a wordy answer to your simple question no I have not had a jamming problem to date. I consider the first time out that the rifle was a bit tight and the mag was dirty. One thing I did change on it was the trigger guard I installed a generic enhanced guard I got from the gun show. It does not intrude into the magwell. I placed a straight edge in the magwell over the trigger guard and the new guard does not touch the straight edge. Maybe the original trigger guard extends into the magwell pushing the mags forward? I am going to reinstall the original one and give it a try. |
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How do you check or adjust the mag latch for correct tightness? After reading responses so far I inserted a couple of mags and they have a bit of back and forth rocking, but not what I would call excessive. I'm having a similar problem, with short stroking and it's cropped up in the last 400 or so rounds fired. I was thinking it was gas related from the powder I'm using for my relaods. Here's what posted on the AR Forum. This thread has got me wondering if it is smething mechanical with the rifle, but regardless, if anyone has experience with my questions below, I'd appreciate a response: Does anyone shoot mainly BH 68 or 68/69 reloads out of your carbine (w/carbine gas system)? If you are reloading what powder are using and is it completely reliable? The reason I ask is I shot around 300 rounds today out of my 16" Patrolman's Carbine, using the max listed load of Ramshot TAC (which I've been told is the same powder BH uses), TAC is a slower burning powder that's supposed to work well with 68-80 grain loads. All my mags have been recently fitted with Magpul followers, this is the first time out for them. 5 of the 6 mags were GI, one was steel; the steel mag was new in the wrapper and probably has less than 200 rounds thorugh it. Springs are as I bought them. When replacing the black followers with the Magpuls I laid all the springs out and they were all very close in length, no more than 1/2 coil difference between shortest and longest, so I didn't think at the time I needed new ones. One mag seemed to function better than the others, but that was after about 150 rounds were put downrange. Up until that point reliability was not good. One of mags had several (4-5) short stroking instances through the whole 30 rounds, some occurring early in the mag while it was still pretty full, others midway or near the end of the mag, others had 2-3 short stroking instances per mag. Prior to this session, I degreased the chamber, lubed the bolt and carrier IAW Bushmaster instructions -- the thing was clean when I started out. Temp was about 65 degrees, it was a beatiful day at the range. I'm looking for advice. My next test will be to run some 52 grain HP using H335 which is a quicker powder, much closer to what's loaded in XM-193. It's worked nicely for me in the past and I suspect it has a more favorable pressure curve than the TAC. Assuming the lighter 52/H335 loads run reliably, then I would look to add weight to the carrier (Tubbs CWS) or run a heavier buffer. Right now I'm using the A2 rifle buffer in an A2 stock. Gas tube is stock, no pigtails or anything like that, and extractor is stock. Key seems to be firmly attached to the carrier. The things that's got me googfy is the rifle when new ran like a champ: XM-193, 52 grain relaods and 68 grain relaods. just recently it's starting to act up. I probably have around 1,200 - 1,500 rounds through this upper/barrel total. |
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To adjust the latch do the following. Grab a round and push the mag latch out farther than your finger can. Once exposed on the left side of the weapon you can spin it around clockwise to tighten counter clock to loosen it. My problem started around 1800 rounds, close to when your problem began. Humm |
Thanks for the tip. I just tightened it two turns, seems to have reduced the slop maybe a bit, kinda hard to tell. Anyway, next time out I'll definitely wring this out with my full power loads. I may also load up some 68 grainers with a reduced charge of TAC to see if less gas has a beneficial effect. I figure between those two approaches I ought to find something that works and either I will have fixed it with the mag latch adjustment or I'll need to add some weight to the carrier. |
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