Nitro

I was having the same issue for a while. I recently sent my M4 back to Benelli for service and after I got it back I took it to the range to test. I ran multiple boxes of Hornady CD without an issue. Benelli said my extractor/extractor cut was out of spec. My guess is that CD is a little more susceptible to an out of spec extractor. After I starting having this issue with multiple brands of ammo, I contacted Benelli.

Update.. Got my M4 back from Benelli after a little over two months (Dec 4th-Feb 14th) and finally got it to the range. I'm happy to report I ran 118 shells of 00 buck from a few brands, mostly Winchester, without a single failure. According to the report from the tech they changed out the extractor and deepened the extractor cut in the barrel extension. I wish I could say my trust in my M4 has been completely restored, but I think its going to take a few more range trips for that. I'm a pessimist, I know. More like 98% restored..;) Thanks again to everyone for all the previous input.

The reviews of the GG&G rail mount are accurate, it does have some play once installed. It also bends easliy which is why I traded up to the IWC mount, didn't realize they stopped making them. If you're looking for a simple setup, there's the CDM ROC-12S that may work for you. It's a clamp mount that uses a pic rail one side and a QD sling mount on the other. I had one on my 870 for awhile until I switched to the magpul forend. The only down side is it eliminates tool-less takedown of the M4, which is why I never used it on mine. You can get one for about $40 on amazon. Just out of curiosity, what happened with IWC?

Spoke with a Benelli rep and he advised sending it in. He also agreed that it's most likely and extractor and/or extractor cut issue. It's going to be at least a six week turnaround, minimum, apparently because it's hunting season and the M4 ain't a hunting gun but hopefully they can sort it out and get it running properly. Thanks for all the replies, I'll keep updating when I know more.

Thank you for the information and advice. Hopefully, Benelli is willing to play ball on the warranty.

Indeed it is rounded off at the bottom edge. I was wondering if this was part of the design, a factory defect, or if it was damaged by something I did and never noticed. Looking at the bolt assembly, I understand what you mean about it being a difficult replacement. I was going to try to contact Benelli on Monday to see what they have to say about it. I really appreciate your offer to replace it. Depending on what Benelli has to say, I may take you up on that. Thank you. Figures I would find a way to break something the Marines couldn't break...

Thanks, I'll check that out. I took a closer look at the extractor and barrel, there's some wear but nothing that seems to be impeding function.

Well, I was going to order a new extractor and spring but now I find both are out of stock at MGW. It's looking more like I'll be sending it to Benelli. Anyone have any recent experience with their CS? How are they fairing these days?

I thought the extractor was held by a captive pin, I'll have to check that out. Any ideas if Benelli would take issue with that should I end up having to send it in?

Unfortunately, I don't know anyone personally that has an M4. Close as I can get is a friend that has a 1301. I even asked my local range/gun shop if they had one used I could compare mine to, no luck. As far a servicing the extractor, I've made sure it's clean and free of any carbon buildup. It doesn't bind on the spring as far as I can tell, but then again, I'm no gunsmith. I'm not sure Benelli would let me get away with just sending in the bolt assembly, even if that would be a alot easier and cheaper. Although, I've never had to send a gun back to a manufacturer before..

I do run it pretty wet, as I was instructed when I bought it. Although I'm careful to keep it out of the pistons and mag tube as I was informed that could cause failures to feed. The shells sticking in the chamber did occur to me the first few times this happened, however I ruled it out as I discovered that when it failed to extract I could tilt the muzzle up and shake the shell out of the chamber. If that didn't work, I could catch the shell rim with a fingernail and easily clear it that way. Point is it really takes minimal force to remove the spent shell when this happens, even when the barrel's hot. I don't see any obvious damage to the extractor, but without another to compare it to, I have no idea if it's out of spec or something.

So, this has been an ongoing issue for me. My M4 has been sporadically failing to extract for a while now. Some background, I got it in Oct 2019 and have kept it mostly stock. Mesa shell carrier & IWC light mount, everything else is original. During my troubleshooting, I upgraded to a full length mag tube and wolff spring, which didn't fix it. I've got about 400 rounds through it, all 00 or slugs. Today at the range, I shot 50 rounds of Win Ranger 00 magnum. First box of 25 went flawless, second box of 25, not so much. I had 3 FTEs. My best guess is the extractor itself is the problem. I checked the whole gun when I got home, no loose components, bolt runs smooth. I also cannot duplicate the issue from manually cycling the action with snap caps or live rounds, no matter how long I try. I've tried shooting different brands (Winchester, Federal, Fiocchi, Hornady) and always the same result, starts off good then goes down hill. The bolt stays back and the shell is left half in the chamber. I clean and oil it after every range trip, she still won't play nice. Oddly enough, it always seems to start when the gun warms up, not sure if that's coincidence or not. I've resisted sending it in to Benelli this long to see if I could sort it out on my own, obviously that's not going well. Any input from those with experience (or ideas) is welcome. I've attached a pic of the malfunction.

So, I'm a little late to this party, but i figured I'd post anyway. Same thing happened to me with this same ammo when I first got my M4 back in 2019, I even posted about it here. I never did really figure out the cause but wasn't really worried since it was only the one type of ammo that did this. I mostly stick to Winchester and Federal these days which hasn't given me a problem. 100% agree with testing your HD ammo first. I had Critical Defense loaded up for almost a month before I realized my M4 doesn't like it very much.

I don't have the TTI, but I do use a ROTH Oversized safety. I find it does make disengaging the safety much easier, especially with a pistol grip. https://rothperformance.com/product/rci-xrail-oversized-safety-button-black/ I tend to keep away from Taran Tactical stuff based on my own experiences, but I know some people love them. Hopefully they'll weigh in here..

Had this very same issue about 9 months back, only it was with Hornady's Critical Defense 8p 00 Buck. Same as pictured, the shells would hang in the chamber. Never did narrow down the cause definitively , especially considering I ran a bunch of other brands and shot types, none of which had an issue. Even the "low recoil" stuff cycled perfectly out of the box. My M4 only had about 200 rounds through it at the time, so I chalked it up to break-in period and moved on. In regards to Fiocchi, I've only fired their Exacta 27p #4 Buck, but never had an issue with it. I searched around, but didn't turn up much. It seems if anyone else had an issue with the Critical Defense in an M4, they didn't post anything about it. It doesn't concern me so much, plenty of other brands to chose from. I prefer Federal or Winchester myself, that's when it's available these days. My only problem is now I have a case of shells I can't use at the moment..