Evolution

That wood is very pretty! What wood is it and where were they made?

Yeah, looks much better! As an aside, I have found that it is not necessary to apply loctite to the mag tube threads and I like the added ease of accessibility to the receiver during cleaning, being able to remove it. Just cranking it on as tight as I can holding the receiver between my knees; stays on tight, and I can remove it as I will without the fuss of having to put it in a vise and heating it. Just an FYI

Agree with truckcop on the hammer business but, am I seeing things? What's with the fried egg appearance on the finish around the bolt release hole?

LOL!!!

Ok, that is interesting. Now I understand what you're talking about. To your knowledge has Mossberg done anything to correct this issue? I didn't drop my gun but, I used a plastic pen tip cover to manually push in the pins and I was able to dislodge them from the retain holes.

lol....I don't know, mine is an older model. I want to say I bought it in 2006 or thereabouts. Iv'e taken it completely apart several times, and before I got the hang of it....they're kinda tricky.....if I didn't break it or screw it up putting it back together wrong, I don't think a little drop is going to hurt it. I had a Mesa Tactical sidesaddle on it for years that uses the trigger housing pin and a screw thru the side of the receiver into the ejector to mount it, that I eventually canned, because the rubber grommets that held the shells in place didn't work anymore.

Thanks for the review information about the size fitting on a Mossberg. I was going to order a 7 round unit for my 590A1 until I read this and then ordered a 5 round unit for best fit.

Same here...must've ben a supply chain problem like everything else. A screw fell out of a server and they couldn't get a replacement. Auto parts, anyone?

Glad I bought mine (2014) before they stopped doing it.

Never give up on CC, it takes a while but they always deliver.

Pulled this out of my safe. The stock has been in it's plastic bag and box ever since I tried the stock and decided that I don't like it's ergos...I read here that someone had trouble with their limbsaver pad deteriorating, looks like this one has too.

Good job! Glad we were able to at least point you in the right direction. Still...I have to say that it is a bit weird that you had to modify your CC spring to effect perfect reliability. That really should not be necessary. I'd love to see you install a standard 7 round mag tube, then install an unmodified CC spring and see what results you get....anyway, as you say, it was an experience which you learned from.😀

Thanks for taking the time for an update. From your original description of the problem, I did not think that it was a bolt or bolt carrier problem because as far as functioning, they were doing what they're supposed to do...the piston impulse was enough to shove it all back enough to lock the bolt open when empty and empty shells are ejecting. I'm still kinda swaying towards the spring, somehow with your particular weapon, not being powerful enough to throw the shells back to actuate the lifter and trip the bolt to go forward. I'm not an expert on these guns either. I was hoping someone like StrangerDanger or unobtanium, would chime in on this thread. Both of those guys could be considered experts IMO. I've never handled shotgun snap caps, so I don't know but, are they as heavy as a live round of buckshot? I would think not, so any spring would be able to toss them back easier than a live round, no? If not, then I would also think that using snap caps for this type of determination would not be accurate? Anyway, I wish that you would have gotten one of CarrierComp's springs to test as they are around 12" longer than OEM springs. I am in no way saying that there could be something else like the rough spots you found contributing to the shells not smoothly getting thrown back onto the rear of the carrier. Keep us up on it!

As always, another fine effort in the quest for the sublime M4 setup SD. One thing that I don't like about this hand guard setup is the sling attachment to the very end of it. It just seems to me that the constant pulling and torquing on the swivel attachment from slinging on and off and general use, especially with the added weight of a full magazine will lead to problems. Do you think that it will hold up? The issue of barrel shadowing is not very important to me. It still seems to me that there is too much given up here (as you have laid out in the negatives summary), with this iteration of hand guard just to mitigate the barrel shadowing issue. BTW, what is that colorful barrel attachment you have on there?

Just throwing this out there but, it might be that you have a weak magazine spring that is not throwing the shell far enough back onto the carrier that is jamming up the gun. You will notice that when the bolt is locked back and you press the bolt release it causes the carrier to flip up into the loading position. Possible with your heavier loads, the recoil is helping to nudge the rounds further back onto the carrier and that's why you don't experience the failure with them. With the lighter loads, does it happen on the last couple of rounds from the mag when the spring is less compressed? It's worth looking into.

Yes, the hammer still has a quarter inch or so of free play as it sits behind the bolt. I keep my hammer greased so it does not move as quickly to make a noise when tilting or shaking the gun. However what you could be hearing also are the pistons tapping the bolt carrier as you are moving the gun fore and aft. just a thought.

When the group is out of the receiver, the bolt is not there to hold the hammer upright, therefore it can rock forward all normal and by by design.

If you're talking about a slight side to side play of the hammer in the uncocked position, that is normal. Also normal when the trigger group is removed for the hammer to rock forward towards the shell lifter when uncocked. You probably just didn't notice this before you did the swap

Silly question to some no doubt, but Iv'e never seen one in person to know. Obviously the comb is plastic but, what about the frame? Aluminum? Thanks!

Normal.

Thank you very much. I understand how it works now. That is exactly the orientation of the oval notches looking down the tube to the rear of the receiver. Just a hair past 12 o'clock. I think those people at Robar knew what they were doing and oriented the tube in the correct position for a collapsable stock, probably because they knew it was a tube for a collapsable stock and it came from the factory oriented that way. Perhaps they even used a collapsable stock or some kind of template to make sure they put the tube on with the correct orientation.😊

While we're on the subject of the recoil tube, I have a question. My Robar NP3 plated M4 came with the fixed PG stock as it was purchased in California (2014). It also came with a 3- position tube which obviously was removed and re-installed by Robar because it was plated along with the rest of the gun. Not being familiar with the collapsable stock and it's internal locking system because Iv'e never seen one but in pictures, I assume that the actual locking cuts in the tube are the three roughly 3/8" long identical OVAL shaped cuts. Is this correct? What are the other 4 cuts located exactly at the 9 o'clock position in the tube for? Do they also aid in locking the stock? And, lastly, if these three identical oval cuts ARE as I suspect, the stock position locking cuts, what position should those oval cuts be in relation to the receiver for the collapsable stock comb to be at the 12 o'clock position? I'm just wondering if I get a collapsable stock, will I be looking at having to adjust the tube. Thanks-

"MILSPEC", going back to the M1907 sling up to present day, is a sling that is 1-1/4" wide. A true MILSPEC buttstock on the M4 would be the collapsable stock, which you have.

https://haleystrategic.com/d3-sling this sling is also an option, they are 1" wide. People speak highly of them.

I assume you're talking here about the Benelli M4? How does that work for you being that the Magpul slings are 1-1/4" wide and the OEM Benelli M4 sling plate in the stock is only 1" wide. The reason that the OP posted his complaint in the first place.