Yeh I have a problem with over insertion all the time......😁😁😁 couldn't contain myself

 

Ha someone got to it first. I havnt tried reloading that agressivly. How much are you talking?

 

It really doesn't take much force to push the magazine up into the path of the bolt. I wonder if a stronger spring in the magazine catch would help.

 

That's weird... you'd think they would notice such a thing in product testing... or even design...

 

I really have to try to overinsert a mag for it to happen and pull back when I send the bolt home, I've never had an issue at the range with it and I run my rifle fairly hard

 

What are you using for magazines?

The new mags from Troy seem very prone to sitting out a round or two if aggressively seated. I have tried this in an AR without issues. GI mags are also easily over-inserted.

On another note, I used a Tango Down ARC mag in my rifle and monopodding the magazine pushed the feed lips up into the path of the bolt carrier and caused a malfunction and shaved material off the top of the feed lips.

 

Tokarev,I am new to this weapon system too, approx 2k down range. I run my guns very hard and had this issue right away. Due to my time on the M16/M4 I was always in the practice of pulling down on the magazine after inserting it. And definitely never slap magazine in like a pistol that is sure to knock a round loose and cause a malfunction. I am learning to live with the issues this weapon has.

 

i run pmags usually and once in a while an emag, imo its more prone on pmags than gi mags or hk hrm's (i've tried 30+ of the gi's, 12 hk's and 15 pmags)

 

Im not sure if im going to the range anytime soon but am curious to test this. Ill try loading some dummy ammo tomorrow since im not keen on trying it with live ammo. Its bugging me and im itching to know more. Fortunately I havnt packed my press away yet.

 

I ran 180 rounds through my rifle this afternoon and was able to induce a number of over-insertion issues using a variety of magazines. The new Troy mags almost always spit a round out the top of the feed lips during insertion. I tried the same Troy mags in a Colt AR with no issues. I even took one of the Troy mags and seated it so hard I chipped off part of the block on the magazine tube but it didn't spit rounds when seated in an AR. I was also able to duplicate this issue with a PMAG. It would almost always spit the top round out of the magazine and would occasionally jump past the mag catch and get pushed too far into the rifle. I can also do the same thing with USGI aluminum mags but these seem to be the least troublesome in this regard.

This is, in my opinion, a design flaw with Bushmaster relying solely on the shape of the magazine catch and the strength of the mag catch spring to stop the magazine's upward travel. I called Bushmaster and asked them about it. The guy I spoke with said he'd never heard of this before and suggested I send the rifle in for service. I'll do that but first I want to make a couple videos showing what I'm experiencing and how much force I'm using when I seat my mags.

 

Since I painted mine im afraid they'll blame any fault to that. It does seem like a design flaw. Ill try it because the more of us that can report the issue maybe they'll make a bulletin or recall or something. Helps in the auto industry anyway.

 

This is a shame, really. The ACR's got a ton of potential but this is going to be a deal killer for me and I'm most likely going to sell the rifle. It would be such an easy fix too. All BFI needs to do is reshape the internal rails so they extend down slightly in front of the chamber so they act as a magazine stop. Of course none of this would matter with an AK magazine interface. Maybe that's why there are no internal ribs. Maybe these interfered with using magazines other than those meant for the M16.

 

I wouldn't sell it. As the acr is meant to be a combat rifle thus frantic reloads may happen im going to see for myself tomorrow. I know I've had to change certainI fundamentals from my ar over my issued one and my acr from those. If I can train myself to consistently reload a way to prevent the issue then ill work with it. If it does it more often then not then ill go dorm there. I suggest before you sell try and make bushmaster work for you.

 

Never experienced this problem with my ACR. With the wife in bed, that's a different story.

Back to the gun though; has this resulted in any sort of FTF or FTE? Curious to see what others might find. Sadly however, it seems more and more to me that the design of the ACR was rushed by the BM engineers. Let's hope that V2 solves whatever current and other problems exist as I'm not fond of being a conglomerate's unwitting guinea pig.

 

Never experienced this problem with my ACR.

I haven't had this problem with my ACR either, I use PMags only in it. After reading this thread, I even tried to make it happen by repeatedly snapping a magazine in with the bolt locked back and wasn't able to make the magazine overide the mag catch with any reasonable amount of force.

I imagine that if I pounded the mag as hard as I could into the mag well it might happen, but I never do that during mag changes. I also think that if the ledge on the magazine catch area was worn, it might allow over insertion to happen during a magazine change even with reasonable force.

 

Of course none of this would matter with an AK magazine interface. Maybe that's why there are no internal ribs. Maybe these interfered with using magazines other than those meant for the M16.

If I can train myself to consistently reload a way to prevent the issue then ill work with it

I may be a novice but I would agree that it may be a compromise to allow for other caliber magazines. In my opinion the phrase "jack of all trades but master of none" might apply to this rifle, well it would be a jack of all trades if they released the conversions. I do hope they release a magnesium lower sometime in the future and will buy it up for sure if they do

 

I can't get the problem to occur with my rifle. I'm using both Pmags and GI mags. I use Pmags in Multigun, and when I shoot from prone I usually slam down in the ground pretty hard in a rush.

My ACR is an early Windham rifle.

 

This only seems to be an issue during reloads when the bolt's locked open. I've not had any problems while reloading with the bolt in battery. Same goes for shooting prone and using the magazine as a monopod.

 

I've never had this problem. I use PMAGS with modified followers (modified for better activation of the bold hold device when empty). I always monopod when prone without issues. I think I had the issue ONCE when I was using a Cammega EasyMag. I've since given that one to a buddy with an AR.

 

Again, please note that I'm not having any problems when shooting prone and while using a magazine for support. I'm only having rounds pop out of magazines during reloads when the bolt is locked back on empty.

 

Tokarev,
How are you inserting the mag? What I mean is are you beer canning or palm on the bottom of the mag? Also do you slap the bottom afterwards or just pull down to check that it is properly seated? Something you might try, and I know this is kind of ridiculous for the price you paid for the rifle, but try to build up the other side(opposite of the mag catch) of the inside of the mag well with tape or something to see if this limits the frequency of over-insertion.

 

I just made some dummy rounds and tested this. I really had to use excessive force to over insert the mag but I did do it. It also lifted the bolt catch so I could not chamber a round. I just pulled the mag down and all was well. So I see your concern. I think someone mentioned a stiffer spring may help. Mike made a good suggestion as well. I tried on the ar and had no such issue.

 

The only way I could get a magazine to over-insert was to use a surplus Israeli Orlite magazine from my stash. None of my other mags would over-insert. Thermold magazines made for the Canadian Military probably work the best in the ACR. I've got quite a few of those. Recently, I've been looking at the Lancer mags and may pick up a couple to try out.

SamM

 

Just tested mine, and i have no problems at all. Slamed the pmag pretty hard in there, also used it as a monopod and everything was good. Id talk to bushmaster about ur issue, maybe they can fix it up.

 

Seems like a slight design flaw. Shouldn't be too difficult to fix though... Any official word from BM or Remmy?

 

Here's a short video demo of what I'm experiencing. It's not really a problem with over-insertion but more an issue with over-insertion leading to double feeds. I believe this is because the upper receiver lacks any sort of feed lips support ribs and the feed lips are allowed to flex and spring open a little with the upward momentum of the ammunition stack in the magazine.

 

wow thats really bad, my overinsertion is only if i add pressure to the mag like a foregrip

eta i just pulled the bolt and tried this and it does it, but i have to slam it alot harder than you were doing it, i wonder how/if they could fix this without replacing a whole lower

 

The feed lip supports need to be installed in the upper. I could maybe make something out of JB Weld or epoxy or something...

 

Wow that is bad. Mine wasn't ejecting but it did go further than the mag catch. Maybe make yourself a mold by pushing some clay in there and plastic wrap so you can get an idea of what you have to do for a fix?