Page 1 of 2 12 LastLast
Results 1 to 10 of 16

Thread: Options for undergassed rifle.

  1. #1
    Join Date
    Oct 2011
    Location
    Alaska
    Posts
    4,112
    Feedback Score
    3 (100%)

    Options for undergassed rifle.

    An acquaintance of mine is having an issue with a 6.8 that has a smaller gas port than his other rifles. He's developed handloads for these rifles and he can't make his new rifle function with his current handloads. He's confirmed it's undergassed by re-checking gas block alignment, switched lowers, and switched BCG's. He is definitely short stroking.

    On my 5.56 carbines I'd just switch to more powerful ammo or reduce buffer weight. In his situation he doesn't want to mess with his handloads, so ammo is out. He has an A2 stock and rifle buffer system, so moving to a lighter buffer is out unless he wants to buy a JP low mass buffer for big $$. He could open up the gas port but I think it's melonited which would make it tough to drill. Would a reduced power spring work?

    Any ideas?

  2. #2
    Join Date
    Jan 2013
    Location
    Western US
    Posts
    2,474
    Feedback Score
    1 (100%)
    Take the weights out of the rifle buffer?

  3. #3
    Join Date
    Oct 2010
    Posts
    962
    Feedback Score
    21 (100%)
    If he knows the gas port size of his other guns just buy a solid carbide drill bit and open it up. That steel is no match for carbide, melonited or not.

    http://www.mscdirect.com/browse/Hole...186+4288243288
    Last edited by Eric D.; 04-26-13 at 01:11.
    B.A.S. Mechanical Engineering Technology

  4. #4
    Join Date
    Apr 2009
    Location
    Texas
    Posts
    4,364
    Feedback Score
    17 (100%)
    Quote Originally Posted by ColtSeavers View Post
    Take the weights out of the rifle buffer?
    This. Buy two rifle buffers. Take the aluminum spacer out of one and replace two steel weights in the other (so it only has 3 steel weights inside and two spacers). Should be around 3.3oz.

    OR, get a Wolff RP rifle action spring.

    Also, consider having him polish the bolt carrier rails (and the bottom of the carrier where the hammer rides) with flitz to make it slicker.
    "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."

  5. #5
    Join Date
    Oct 2011
    Location
    Alaska
    Posts
    4,112
    Feedback Score
    3 (100%)
    Thanks Buford. I was having trouble finding out what was on the inside of the rifle buffer. I know what's in the carbine buffers and A5 buffers, but I couldn't find what was in a rifle buffer.

  6. #6
    Join Date
    Apr 2009
    Location
    Texas
    Posts
    4,364
    Feedback Score
    17 (100%)
    Quote Originally Posted by AKDoug View Post
    Thanks Buford. I was having trouble finding out what was on the inside of the rifle buffer. I know what's in the carbine buffers and A5 buffers, but I couldn't find what was in a rifle buffer.
    No prob. The spacer takes up the space of roughly two steel weights. It weighs almost nothing.

    EDIT: a mil spec rifle buffer just has 5 steel weights and the rubber spacer disks + 1 of the above mentioned aluminum spacers.

    I have a buddy who shoots heavy 80gr handloads and he had me remove the spacer and insert two additional steel weights from a carbine buffer (I think it ended up between an A5H3 and A5H4 in weight....just above 6oz). He prefers to use the std power rifle spring and he has been quite happy with the results.
    Last edited by BufordTJustice; 04-26-13 at 02:00.
    "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."

  7. #7
    Join Date
    Jan 2013
    Location
    Western US
    Posts
    2,474
    Feedback Score
    1 (100%)
    Quote Originally Posted by AKDoug View Post
    I was having trouble finding out what was on the inside of the rifle buffer. I know what's in the carbine buffers and A5 buffers, but I couldn't find what was in a rifle buffer.


  8. #8
    Join Date
    Oct 2011
    Location
    Alaska
    Posts
    4,112
    Feedback Score
    3 (100%)
    Thanks Colt. I've seen that pic dozens of times and no search wording I used could find it last night.

  9. #9
    Join Date
    Sep 2007
    Location
    AZ
    Posts
    32,833
    Feedback Score
    14 (100%)
    I'd confirm undergasment by shooting the upper on a carbine lower with a H or Carbine buffer before proceeding.

    I like solid confirmation before I get to changing anything.
    "What would a $2,000 Geissele Super Duty do that a $500 PSA door buster on Black Friday couldn't do?" - Stopsign32v

  10. #10
    Join Date
    Oct 2011
    Location
    Alaska
    Posts
    4,112
    Feedback Score
    3 (100%)
    Thanks Mark. I also suggested that. Frankly, I think he just needs to hop up his handloads a bit to make them work. Unfortunately that will make them too hot for his overgassed 6.8's and then he'll need a heavier buffer for them.

Page 1 of 2 12 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
  •