Page 6 of 7 FirstFirst ... 4567 LastLast
Results 51 to 60 of 65

Thread: Adams Arms/VLTOR A5 fail to eject

  1. #51
    Join Date
    Jul 2007
    Location
    New Jersey
    Posts
    7,152
    Feedback Score
    4 (100%)
    Quote Originally Posted by gwilki2 View Post
    It's more like, this is the way I chose to build my gun, in theory it should work just fine, so I am going to make it work. Call it the engineer in me, but I'm not going to just drop the part because it's giving me a headache.

    Well you see a little something new here each and every day. Always fascinating.

  2. #52
    Join Date
    Apr 2013
    Posts
    11
    Feedback Score
    0

    Adams Arms/VLTOR A5 fail to eject

    Ahh, the much awaited update....

    First of all, some people may think I decided to ignore everyone's advice. That's not true. Many people gave good advice. A few threw in some anti-piston and anti-A5 advice, which I did choose to ignore. I wasn't going to just get rid of either one in order to "fix" this problem. I wouldn't call that fixing the problem, I'd call it building a new gun. My next new gun, which will have nothing to do with this gun, is going to be a DI AR with standard carbine RE chambered in 300BLK.

    Anyway, there were 3 specific suggestions that I did choose follow.

    1) Swap uppers/lowers with a functioning rifle.
    2) Use some better ammo.
    3) Lighten the buffer.

    So the story goes like this...

    1) Friend with functioning AR was completely willing to come to the range with me and swap parts. Unfortunately, other things kept getting in the way, so this never actually happened (yet).
    2) Ordered 250 rounds of Lake City M855.
    3) Ordered a standard carbine buffer and a kitchen scale. Upon receiving the scale, weighed my buffer, and it weighed 6.8oz (HAHAHAHA). Apparently the guy I ordered the Vltor parts from sent me the heaviest buffer Vltor makes (A5H4, all tungsten weights). Anyway, removed 2 of the tungsten weights and replaced with 2 steel weights from the carbine buffer, bringing the weight down to the 5.3oz it should have been as an A5H2.

    Result:

    Loaded 25 rounds of M855 into 30rd PMAG. All fired, all cycled no problem, bolt locked back on empty mag.
    Loaded 30 rounds of the old Independence XM193 into various magazines. All fired, almost all ejected (some rather weakly, landing 6-12 inches away), 1 cycled the next round, none locked the bolt back on empty mag.
    Loaded M855 into various magazines, 1 failed to feed, the rest fired and cycled fine.

    Came home, did a quick inspection of the buffer tube, and didn't see any real damage other than some scratching all around on the inside... very minor looking.

    So it sounds like it was, and still is, a buffer weight issue. I'm going to change the last tungsten weight to steel and it should function fine with all my ammo. If it needs to be lighter than that, I'll need to order a new A5H0 buffer, because the last tungsten weight in mine is the one with the spring attached (which I guess I could swap for steel one without a spring, but I have no more steel weights anyway).

    Thanks for all the help guys!
    Last edited by gwilki2; 08-22-13 at 21:32.

  3. #53
    Join Date
    Nov 2010
    Location
    MI
    Posts
    3,055
    Feedback Score
    21 (100%)
    Über heavy buffer.

    Makes perfect sense.

    Would definitely cause short stroking.
    Black River Tactical
    BRT OPTIMUM HFCL Barrels - Hammer Forged Chrome Lined 11.5", 12.5", 14.5"
    BRT OPTIMUM Barrels - 16" MPR, 14.5" MPC, 12.5" MRC, 11.5" CQB, 9" PDW
    BRT EZTUNE Preset Gas Tubes - CAR and MID
    BRT Covert Comps 7.62, 5.56, 6X, 9mm
    BRT MarkBlue Gas Tubes - BRT EXT, EXC and PDW Lengths
    BRT MicroPin Gas Blocks - .750" & .625"
    BRT MicroTUNE Adjustable Gas Blocks
    BRT CustomTUNE Gas Ports

  4. #54
    Join Date
    Jul 2008
    Location
    Texas
    Posts
    3,742
    Feedback Score
    1 (100%)
    The scratching is from the fact that the carrier isn't(and can't with a short stroke piston) operate the way it was designed to.

    The gun as designed was an inline piston gun...the carrier ran nice and neat straight to the rear because the forces acting upon it were nicely centered inside of it.

    Piston conversions change where the piston is. Instead of being centered inside of the carrier, it moves to the front of the gun and drives an op rod into the area where your bolt carrier key used to live(I realize you probably know this part.) When it's impacted off center, with the relatively short and small bearing surfaces, the carrier tilts as it's driven rearward into the receiver extension.

    The good news is that to my knowledge this hasn't led to many serious issues, and the world is okay if not perfect. The bad news is that your inner engineer will now have to deal with something that's not working as designed, and the worse news is that it's due to a "fix."
    Last edited by thopkins22; 08-23-13 at 00:47.

  5. #55
    Join Date
    Apr 2009
    Location
    FL -Where it's summer 10.5 months out of the year
    Posts
    4,114
    Feedback Score
    17 (100%)
    Quote Originally Posted by thopkins22 View Post
    The scratching is from the fact that the carrier isn't(and can't with a short stroke piston) operate the way it was designed to.

    The gun as designed was an inline piston gun...the carrier ran nice and neat straight to the rear because the forces acting upon it were nicely centered inside of it.

    Piston conversions change where the piston is. Instead of being centered inside of the carrier, it moves to the front of the gun and drives an op rod into the area where your bolt carrier key used to live(I realize you probably know this part.) When it's impacted off center, with the relatively short and small bearing surfaces, the carrier tilts as it's driven rearward into the receiver extension.

    The good news is that to my knowledge this hasn't led to many serious issues, and the world is okay if not perfect. The bad news is that your inner engineer will now have to deal with something that's not working as designed, and the worse news is that it's due to a "fix."
    You've been reading Stoner's patent calling the AR an "inline piston", haven't you?

    Stop it!

    For anybody who is curious, it's readable fo-free on Google patents.
    "That thing looks about as enjoyable as a bowl of exploding dicks." - Magic_Salad0892

    "The body cannot go where the mind has not already been."

  6. #56
    Join Date
    Jul 2008
    Location
    Texas
    Posts
    3,742
    Feedback Score
    1 (100%)
    Quote Originally Posted by BufordTJustice View Post
    You've been reading Stoner's patent calling the AR an "inline piston", haven't you?

    Stop it!

    For anybody who is curious, it's readable fo-free on Google patents.
    Well...yes. But then it made sense when I thought about how the bolt and carrier interface and their position within the rifle.

  7. #57
    Join Date
    Feb 2012
    Posts
    407
    Feedback Score
    44 (100%)
    Glad you got it working. So it turns out that the stock A5 system wasn't to blame... fancy that .

  8. #58
    Join Date
    Jul 2013
    Posts
    293
    Feedback Score
    0
    Quote Originally Posted by bruin View Post
    Glad you got it working. So it turns out that the stock A5 system wasn't to blame... fancy that .
    Well, since the buffer was way to heavy, and it was a Vltor A5 buffer...

  9. #59
    Join Date
    Feb 2012
    Posts
    407
    Feedback Score
    44 (100%)
    Yeah, he thought it was stock A5H2 buffer when it was really the A5H4. That's like installing a H3 buffer thinking it's a H. The stock A5 buffer worked...
    Last edited by bruin; 08-26-13 at 16:12.

  10. #60
    Join Date
    Dec 2008
    Location
    Where the 2nd Amendment still lives.
    Posts
    2,729
    Feedback Score
    5 (100%)
    He's still having some issues that needs to be resolved before calling the rifle good, those failures to extract are a concern and the scoring inside and around the front of the buffer tube may not be carrier tilt but bad fit between the bolt and buffer tube.
    We are all inclined to judge ourselves by our ideals; others, by their acts.

Page 6 of 7 FirstFirst ... 4567 LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •