In order to participate in the GunBroker Member forums, you must be logged in with your GunBroker.com account. Click the sign-in button at the top right of the forums page to get connected.

Problem with DPMS AR-15

milesmiles Member Posts: 2,548 ✭✭✭✭✭
edited October 2013 in Ask the Experts
Won an auction on a (looks new) DPMS AR-15 last week and first time I pulled the charging handle back and released it to chamber a round and the bottom of the bolt somehow snagged the small pin and spring that holds the buffer in the buffer tube and * it out of the hole it sits in. The little spring and the buffer retaining pin are toast.

Any idea how to identify and fix the problem. I called DPMS and explained the problem and all I got was a song n dance along with their heart felt sadness and a charge on my credit card for a new little spring and retaining pin.

Need to find out what's wrong before I trash the new spring and retainer pin when it gets here other than that's what I get for buying/winning a DPMS in the first place.
· Share on FacebookShare on Twitter

Comments

  • MG1890MG1890 Member Posts: 4,460 ✭✭
    edited November -1
    Maybe the buffer tube is not screwed in far enough to hold the plunger down? Got a picture of the hole so we can see the buffer tube?
    · Share on FacebookShare on Twitter
  • Riomouse911Riomouse911 Member Posts: 3,492 ✭✭✭
    edited November -1
    I agree with the post, the buffer tube has to contact the retaining pin on the pin's "shoulder" enough to keep it from popping up and out. It is one of those trial and error type things that new builders (or folks switching stocks) occasionally discover.

    Hopefully there is no damage to the bcg or the hole the pin sits in. Good luck with your fix!
    · Share on FacebookShare on Twitter
  • milesmiles Member Posts: 2,548 ✭✭✭✭✭
    edited November -1
    quote:Originally posted by MG1890
    Maybe the buffer tube is not screwed in far enough to hold the plunger down? Got a picture of the hole so we can see the buffer tube?

    Don't have a camera that's good enough to get a picture of the small area where the problem is.

    I will try to loosen the Castle nut up and screw the buffer tube one complete turn in and see if that works. Thanks for the help.
    · Share on FacebookShare on Twitter
  • Laredo LeftyLaredo Lefty Member Posts: 13,451 ✭✭✭
    edited November -1
    You say the gun "looks new". You might contact the person you bought it from and ask if he had ever used or tried to use the gun.

    It sounds like you have a new gun incorrectly assembled at the factory. As mentioned, screw the buffer tube in until it contacts the buffer retaining pin and the edge of the tube goes over the edge of the pin keeping the pin in the hole but allowing the protrusion on the top of the pin to hold the buffer in place.

    I don't know if DPMS test fires their guns, but that problem would have been found if they fired or even function tested the gun when it was assembled.
    · Share on FacebookShare on Twitter
  • milesmiles Member Posts: 2,548 ✭✭✭✭✭
    edited November -1
    quote:Originally posted by Laredo Lefty
    You say the gun "looks new". You might contact the person you bought it from and ask if he had ever used or tried to use the gun.

    It sounds like you have a new gun incorrectly assembled at the factory. As mentioned, screw the buffer tube in until it contacts the buffer retaining pin and the edge of the tube goes over the edge of the pin keeping the pin in the hole but allowing the protrusion on the top of the pin to hold the buffer in place.

    I don't know if DPMS test fires their guns, but that problem would have been found if they fired or even function tested the gun when it was assembled.


    After looking inside the lower, the small cut-out in the tube that the pin sticks through is not exposed by at least one complete turn of the tube.
    No way this rifle could have been tested at DPMS and there are no marks on the castle nut where the previous owner messed with it and the rifle appears to be 100% new and unfired.
    My guess the previous owner saw there was a problem and auctioned it off.

    No big deal, I ordered new pin and spring from DPMS and a Castle nut wrench from Brownells. I needed the wrench anyway so, it's all good.[:)] Again , thanks for the help.
    · Share on FacebookShare on Twitter
  • MobuckMobuck Member Posts: 14,163 ✭✭✭✭
    edited November -1
    They will actually work fine w/o the retainer. It basically holds the buffer in place when the rifle is opened. Obviously something amiss in the assembly. Had you opened it up to clean or lube it?
    · Share on FacebookShare on Twitter
  • midnightrunpaintballermidnightrunpaintballer Member Posts: 2,233 ✭✭✭✭✭
    edited November -1
    it sounds like your buffer tube is out of spec if it doesn't hold the pin while positioned correctly. If your buffer tube has a groove for the pin to sit in, the pin will more than likely be completely covered by screwing in the buffer tube another full rotation. Cut the groove deeper. Don't screw up the threads. Problem solved.
    · Share on FacebookShare on Twitter
  • TxsTxs Member Posts: 17,809 ✭✭✭
    edited November -1
    As has been said, it certainly sounds as if the receiver extension was just improperly installed.

    If so, what would concern me is that getting this assembly step right is very basic stuff. The fact that it failed on the first hand cycling demonstrates that it was WAY out of spec, meaning seriously shoddy work.

    Are you sure this is a genuine factory DPMS rifle or could it have been assembled by an individual using one of their receivers?
    · Share on FacebookShare on Twitter
  • tsr1965tsr1965 Member Posts: 8,682 ✭✭
    edited November -1
    Lets all remember, that DPMS, and Bushmaster are now under the same empire, with Remington. So, with that said, and the recent quality issues with almost every one under that banner, including NEF, H&R, Marlin, along with Remington, DPMS, and Bushmaster, ANYTHING could happen.

    Best
    · Share on FacebookShare on Twitter
  • andeanincandeaninc Member Posts: 28 ✭✭
    edited November -1
    The crap I'm reading in all this is that much assumption is made that this is the fault of DPMS. You don't know if they assembled the rifle, or not. Because the components are from that maker, you assume they assembled it... but you and most of the commenters don't know that to be true because you haven't asked the seller about its history. There are a lot of components being sold these days and made into complete rifles by amateurs. This may, or may not, be the case with this rifle. Let's put down the pitchforks and burning torches long enough to get the facts before we pass blame.

    My experience with DPMS has been wonderful. I'd hate to see any company's reputation harmed from not getting all the facts.
    · Share on FacebookShare on Twitter
  • nononsensenononsense Member Posts: 10,928 ✭✭✭✭
    edited November -1
    andeaninc,

    Please bear in mind that this is a public forum for the sharing of information and opinions from a large cross section of firearms owners. Their opinions and experiences may differ radically from those of yours and others but that's part of the excellence of GB forums, the broad base of folks and their experiences.

    On the other hand, I've had the experience of manufacturing and assembling more AR15 and AR10 rifles than most of the members put together. So when I state that I have rejected a substantial number of parts from some suppliers on occasion, including but not limited to DPMS, you can take it as fact. They, like every other manufacturer have their flaws and drawbacks. Everybody makes mistakes sometimes.

    It's nice to have some defend a manufacturer but let's keep a little reality in place.

    Best.
    · Share on FacebookShare on Twitter
Sign In or Register to comment.