What would cause this damage to a buffer?

Discussion in 'Maintenance & Gunsmithing' started by bolus, Apr 1, 2015.

  1. bolus

    bolus
    Portland
    Well-Known Member 2015 Volunteer 2016 Volunteer

    Messages:
    3,601
    Likes Received:
    8,023
    Noticed this when cleaning last night. End of the buffer is mushroomed out and dragging on the spring. AR15, home built and this was from a parts kit from PSA (and it was cheep). Gun has been working like a charm.

    I'd imagine its hitting the back of the buffer tube with a lot of force for some reason. It could be it was a very cheep part. Its an 80% lower build and I did not expect it to successfully work so stuck with the cheep parts.

    3WCsRCw.jpg
     
  2. Stomper

    Stomper
    Ungovernable!
    Become Ungovernable! Gold Supporter

    Messages:
    14,273
    Likes Received:
    25,089
    Although they do bottom out (hence the "rubber" bumper on the end) the buffer could be slamming into the rear of the buffer tube too hard, or you have either a weak buffer spring, or an out of spec buffer that's too light or just cheap/flimsy allowing the bumper to shove in, and/or you're shooting some REALLY hot ammo.

    Start by replacing the buffer and see if the trend continues.
     
    bolus likes this.
  3. eldbillbo

    eldbillbo
    clackamas
    New world samurai and a redneck none the less Bronze Supporter

    Messages:
    3,214
    Likes Received:
    1,088
    your not running one of those light weight bolt carrier groups are you?
    my guess a lot of gas/hot loads (although too much gas tends to also cause function problems , poor buffer spring and cheap buffer or a combination of 2 or 3 .

    Your problem is most likely in the spring and being a cheap buffer. unless there is some kind of freak problem like a under sized buffer tube

    I hate say just go buy another buffer (most likely you have a cheap Chinese made buffer) and have it happen again . I wouldn't put a new on in without replacing the spring too springs are cheap make sure mil spec or better.
    I would also suggest a heaver buffer or heavier carrier or a extra power buffer spring .
     
    Last edited: Apr 1, 2015
    Stomper and bolus like this.
  4. bolus

    bolus
    Portland
    Well-Known Member 2015 Volunteer 2016 Volunteer

    Messages:
    3,601
    Likes Received:
    8,023
    thanks, my plan was just replace the parts with better ones and that this was just a symptom of a cheep part. Wanted to make sure it wasnt indicating something worse. I'm still surprised it works given I made it. probably has seen 200-300 rounds with no problems.
     
  5. B5Ben

    B5Ben
    Boise
    Well-Known Member

    Messages:
    1,213
    Likes Received:
    795
    Ya I would definitely start with the spring and buffer replacements with quality parts.
     
  6. oli700

    oli700
    Rogue Valley
    Well-Known Member

    Messages:
    1,323
    Likes Received:
    1,232
    Way over gassed , broke the roll pin in the buffer, the quality of the buffers in the PSA kits are fine you just broke the roll pin hammering the bumper into the buffer body

    What barrel and gas system length do you have on this rifle ?
     
    IronMonster likes this.
  7. Velzey

    Velzey
    Gunsmith
    Büchsenmacher Bronze Vendor Bronze Supporter

    Messages:
    2,722
    Likes Received:
    4,955
    I would also say over gassed! But, as of lately, I've seen some cheap import parts coming in. And I mean cheap! I picked up two similar buffers off an auction site and after 50 rounds they looked exactly like this! Junk!!

    There was no anodizing at all so it was dead soft! The rubber actually had the smell of a harbor freight store!
     
    cooper likes this.
  8. Stomper

    Stomper
    Ungovernable!
    Become Ungovernable! Gold Supporter

    Messages:
    14,273
    Likes Received:
    25,089
    BLASPHEMY!!! :eek:
     
  9. bolus

    bolus
    Portland
    Well-Known Member 2015 Volunteer 2016 Volunteer

    Messages:
    3,601
    Likes Received:
    8,023
    There is no roll pin in the buffer. Im thinking that this buffer is made for a squirt gun.

    vZz0GaO.jpg

    I did not make the upper. Its a complete Anderson upper (wasnt that confident of the my assembly abilities to do the upper)
     
  10. eldbillbo

    eldbillbo
    clackamas
    New world samurai and a redneck none the less Bronze Supporter

    Messages:
    3,214
    Likes Received:
    1,088
    the only way it could be over gassed to the point that a H buffer or extra power spring can't solve would be if the gas port is over sized. Unlikely but possible that falls under a freak issue such as a undersized buffer tube but these thing can happen with cheap parts. . bro in law got s JSE 20" barrel that had a gas port drilled for a carbine so it was under gassed contacted JSE about it and their solution was to tell us what bit size to get to fix it ourselves .

    I am leaning that thats not even a PSA buffer looks like a Chinese made one
    but like i mentioned it could be a combination of the mentioned problems. if its a oversized gas port you may need a combination of a H buffer and extra power buffer spring or a H2 or H3 buffer .
     
    Last edited: Apr 1, 2015
  11. IronMonster

    IronMonster
    Free Idaho!
    Opinionated Member Lifetime Supporter

    Messages:
    4,792
    Likes Received:
    8,692
    I think that is a PTAC buffer sold by PSA, but not a PSA buffer. All the actual PSA buffers I have got (which is quite a few) have been black.
     
  12. IronMonster

    IronMonster
    Free Idaho!
    Opinionated Member Lifetime Supporter

    Messages:
    4,792
    Likes Received:
    8,692
    On second thought I think even the PTAC buffers have a roll pin...
     
  13. v0lcom13sn0w

    v0lcom13sn0w
    45th Parallel
    Silver Supporter Silver Supporter

    Messages:
    3,296
    Likes Received:
    6,436
    get a spikes st-t2 buffer
     
    bolus likes this.
  14. bolus

    bolus
    Portland
    Well-Known Member 2015 Volunteer 2016 Volunteer

    Messages:
    3,601
    Likes Received:
    8,023
    Wouldnt over gassing result in a lot of malfunctions? Im thinking now that this might not be a PSA part. I gave my step son a 80% with all the parts for his birthday for him to build and I spent a lot more on his. I really went cheep with this one. I dont think I spent over $400 for the entire thing (plus the 80% jig).

    Thanks for the info. Good stuff I needed to learn about.
     
  15. IronMonster

    IronMonster
    Free Idaho!
    Opinionated Member Lifetime Supporter

    Messages:
    4,792
    Likes Received:
    8,692
    Overgassing beats the heck out of the rifle, is hard on everything but usually results in a pretty reliable rifle (has been my experience, which is limited)
     
  16. bolus

    bolus
    Portland
    Well-Known Member 2015 Volunteer 2016 Volunteer

    Messages:
    3,601
    Likes Received:
    8,023
    Thats what I have in my 50 beowulf build. Its doing just fine after 200 or so rounds (unlike my shoulder)
     
  17. v0lcom13sn0w

    v0lcom13sn0w
    45th Parallel
    Silver Supporter Silver Supporter

    Messages:
    3,296
    Likes Received:
    6,436
    i have the spikes st-t2 paired with a surefire procomp 556. BEST mods i made to my rifle. hands down.
     
  18. 308

    308
    ΜOΛΩΝ ΛΑΒΕ
    ΜOΛΩΝ ΛΑΒΕ Silver Supporter

    Messages:
    3,945
    Likes Received:
    9,386
    I agree with the Spikes buffer, but I'll add the addition of the Tubb Precision AR-15 CS Buffer Spring
    http://www.davidtubb.com/ar15-tubb-parts/ar15-bufferspring

     
    Last edited: Apr 2, 2015
    IronMonster and bolus like this.
  19. IronMonster

    IronMonster
    Free Idaho!
    Opinionated Member Lifetime Supporter

    Messages:
    4,792
    Likes Received:
    8,692
    I run Tubbs springs in most of my AR's (all but the super cheapies) I also run the Tubbs extractor and ejector springs. As he says, springs are what make your AR run.
     
  20. oli700

    oli700
    Rogue Valley
    Well-Known Member

    Messages:
    1,323
    Likes Received:
    1,232
    Wow, never seen that before.....that would would be a big red flag to me , missing roll pin. Wonder if it was made that way on purpose or it just got pushed through and it got missed, bummer good luck getting it straight
     

Share This Page