Hey guys sorry if this is really long but I like to provide all the info I can. First off the rifle in question is a Bushmaster M4 type "patrolman's carbine", the ammo is Sellier and Belloit 55gr FMJ, and mags are C products with Magpul followers. I've put aprox. 1k rounds through her and keep her pretty clean.
The other day I was out firing some rounds when it kept having this problem. I would fire a shot and a jam would occur. The fired case would still be in the chamber and the next round would get jammed into the back of it. I would clear the jam and have to close the bolt to get the case out of the chamber, usually with minimal effort. By like the 6th time it happened the charging handle felt like it was stuck and required gorilla strength to pull out the case. I looked at the case and it didn't seem damaged or anything, except on one where the lip of the case where the bullet sits was a little bent inward nothing to bad though. I took her home and gave her a good cleaning but this time I used CLP to lube it instead of remoil like last time, cause when I took her apart she looked pretty dry inside. Damn remoil in the aerosol can, avoid it like the plague!! I took her out today and shot a full 30 rd mag with no problems. Then on the second mag it started to happen again. Only twice this time though and one of the times after pulling out the mag the chambered case fell out cause I had the rifle pointed up at the time.
Sorry here's the questions. Anyone have this happen to them? And if so did you fix it? This has only recently started to happen and I've read it may be the extractor spring, but my rifle is still pratically new and I think it's wierd if the spring is worn out so quickly. I checked the extractor itself and it looks brand new so I don't think it's that. I ordered a new spring kit from Bravocompany.com and should have it this week hopefully. Has anyone used this kit and is there a difference between a blue insert, the one in mine now, and the black one it comes with? Here's a link for it in case anyone wonders which one, [Only registered and activated users can see links. ]
Well once again sorry for the long post and thanks to anyone and everyone that can help me out with any info.
Last edited by Guatariccan : 08-08-2008 at 08:37 PM.
Reason: Clearer thread title to include what exact help is needed
Sounds like you figured it out on your own. the shorter barrels have problems with the extractor slipping off the case rim on extraction. I put an o ring around the extractor spring on my rifles. I can't remember off the top of my head if its a #30 or a #60 though. My father in law was having that problem and he fixed it by cleaning out the powder residue and brass filings that had acumulated under the extractor. On some of the Sellier & Belloit cases I've inspected, I noticed that the case rim is rounded off more than other makes. You may want to try other brands of ammo
Well thanks for the advice mole man. I just picked up a box of UMC for the heck of it and I'll compare the cases to see if there is a difference between the two. Once again thanks.
So you use the new spring with the o ring I take it J? You ever have a problem with too strong of extraction, if that possible? By that I mean has it ever tore off the rim of the cartridge for you?
Well I just got my BCM extractor spring upgrade kit and installed it with the o-ring. I'm going to take her out next week and hopefully it'll solve my problem. I'll report my results just in case someone is out there just like me, wondering what to do and if this will fix the problem.
Sounds like the bolt is trying to open too soon (M4 type should be 16" barrel). By correcting the extractor be leery of ripping heads off. You may have to adjust gas system(ie:enlarge gas hole in barrel, acquire "pig tail" gas tube,etc...).
Need help/ advice on extraction problem
extraction problems
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