Buffer Detent and Spring Broke...? With Pictures.

AR/M4 AR Technical Discussion
1

Just a normal day at the range except newly installed COLT LPK, magpul buffertube one point sling attachment, and some hollow points(cause the range is stingy on ammo types). I shot about ten shots, then let my buddy shoot some in which he got three shots off before a misfire. After a few thousand rounds through this rifle that was the first ever FTF, did an inspection, and kept shooting. Two shots after that, another misfire. Did an inspection to find my detent spring in the mag!? WTF. Took the lower off to find the buffer retainer missing. Found it in the buffer tube. I have no idea what happened!

Recently, I bought the Magpul One-point Sling thing, and the gun store put it on for free! In the process he forgot to hold in the buffer retainer so it shot across the room. He reinstalled it all fine and dandy! I installed the LPK by myself but not once touched anything around the buffer tube.

My question is what the heck happened??

Lucky me, I found a buffer retainer in my LPK kit. Yeah for being a noob and not installing the whole thing. I guess.

2

sounds like the buffer tube was not screwed into the reciver extension far enough. If the nut was not staked to the magpul sling plate your stock could have been shifting back and forth and allowed the part enough clearence to pop out.

3

After some quick research on installing the buffer retainer I found that the guy may not have installed it correctly. I don’t think it sat, all the way in under the buffer tube, properly. Therefore, it popped out! :frowning: I also don’t have the tool to remove the castle nut and reinstall the new one.

4

Yeah, that’s what I’ve decided after watching how to install my new one. Sucks I didn’t research that before when I originally bought the LPK or I might have caught that.

Thanks for the quick reply though!

5

Ya no worries do it your self next time its pretty easy.

6

Got what you paid for it then. :lol:

The rifle will work fine without the buffer retainer, just makes it difficult to open and close.

7

the exact same thing happened with me… had my local smith install a free float rail and when I got it back and proceeded to the range, I did a quick once over (the pilot in me always doing a “pre-flight check”) I noticed the birdcage was not even hand tight and so I opened it up and noticed my buffer detent spring in 2 pieces, and retainer missing I have no idea why he even messed with the buffer tube to install a forerail, I had to canabalize a second rifle until I could get home and order new parts… lesson learned… do the work myself next time…

8

Ok thanks for the reply, and I soon remembered they did do it for free. lol. Oooh they sure got me! bastards.

New question: What the hell is this? It looks like a factory cut until you look at the corner where it’s jacked up. Lines up perfectly with the hole. I noticed when I slip the new retainer in… Is that standard?? Cause google images shows NOTHING like this on ANY buffer tube.

9

is that white metal around the edge of the hole?

10

No that’s just my maglight. It’s kind of a scuffed up black/gray.

BUT definitely not the black that’s around the rest of the buffer tube threads.

11

well looks wrong to me but I dont own any magpul buffer tubes and the designs do vary a bit sometimes.

12

It’s DPMS buffer tube, I just had the Magpul Buffertube One Point Sling attachment installed onto it.

UMM, I mean this thang. http://store.magpul.com/product/MAG500/53

13

Hard to tell from that pic but is the lip of the receiver extension bent around the hole for the buffer retainer?

good on the left, crap on the right.

14

It look as if that it was made that way. I just sent an email to DPMS asking if that’s standard for their buffer tubes.

Again tho, the corners on that whole look a little screwed up.

See here? Maybe this is better… The brighter lower corner on that cut kinda makes it look non factory. or crappy factory.

Hopefully tomorrow, DMPS will reply, and I’ll go get the wrench to remove that buffer tube. It almost looks to me as if the retainer was pulled out and broke off that section that had been routed out on the bottom of the tube?

15

I got the idea to show the overlap on the btube. And that little corner pretty much got raped by the retainer pulling out. I’m assuming the cutout is for the retainer post to get the tube in farther, but then that doesn’t make sense when you actually try it. It would just get caught on the post…

16

If the metal is white I’d assume it was broken off by the retainer on its way out of the hole. If not then it’s probably DPMS’s halfass way of getting the tube to capture the retainer with binding on it. Maybe they paint penned over the white and that is the color difference you’re seeing.

the LRE should have a timing lip on it like this.

17

It does have that. I can see that even without taking it out. I guess I’ll just have to wait for them to reply to see if that’s their hole.

I’m buyin another tube either way. Recommend any?

18

Hard to tell from the picture, but it looks like the receiver extension should have been screwed in one more revolution.

19

I agree. It sucks so much, cause I just made friends with the guy who installed the Magpul ASAP. Brand new black rifle gun store just down from my house! I was so excited!! Now, im kinda peeved… I’ll lettem know what’s up.

20

You can probably screw that one in one more turn, that’s why the cut. It’s not GI but it works. For parts I’m solidly with BCM. I know first hand that Paul wants to do it right.