Page 1 of 2 12 LastLast
Results 1 to 10 of 17

Thread: Nitride treated bolts and barrel extensions.

  1. #1
    Join Date
    Jan 2008
    Location
    Roaming
    Posts
    889
    Feedback Score
    0

    Nitride treated bolts and barrel extensions.

    Is there anyone here that works in a lab or company(one that does not Nitride parts) that can check the hardness of material?
    I already know the answer but it' more like I need it verified by someone not connected to any company that Nitrides parts but is involved in the firearm community and interested in the truth.
    I can send a few Nitride treated barrel extensions. I do not think I have any Nitride treated bolts but I'll check.
    My suspicion is Nitride treatment of parts that have already been hardened to 60C by carburizing anneals the parts to the point that the lugs of barrel extensions and bolts compress under the impact and headspace increases as a result.
    I have already talked to a couple of companies that nitride parts and of course they say Nitride treatment does not soften the parts and also does not change the torque of barrel extensions installed on barrels. I've been installing barrel extensions and re-torquing barrel extensions for 12 years.
    I've also read on forums over the years that Nitride treament causes the parts to become brittle due to hydrogen infusion. from the testing I have done that is not true. The parts are softer not more brittle.

  2. #2
    Join Date
    Apr 2013
    Posts
    248
    Feedback Score
    6 (100%)
    Nothing to offer, except your post reminded me of this thread...
    https://www.m4carbine.net/showthread...nsion-wear-FYI

  3. #3
    Join Date
    Jan 2008
    Location
    Roaming
    Posts
    889
    Feedback Score
    0
    Thanks, forgot about that one. I stopped using melonite treated extensions several years ago. IMO barrels and carriers are fine, bolts and extensions that are subject to impact are not.
    The top photo in that thread shows what I am seeing also. It depends on the bolt thrust generated by the cartridge diameter and pressure of the cartridge, 5.56 will be the least effected, 6.8 more and Grendel even more so due to area x PSI.
    Last edited by constructor; 02-14-19 at 11:59.

  4. #4
    Join Date
    Aug 2011
    Location
    N.E. OH
    Posts
    7,595
    Feedback Score
    0
    I may be able to perform hardness. Let me do some digging, but it would take a while. I could do 15T scale, but what you want may be too hard for us to test, and Id have to wait till Im at another facility.

    From my non-working knowledge of nitriding, hydrogen embrittlement is a non issue as no hydrogen is generated by the process. I thought it was a molten NaCN or KCN bath.
    Last edited by MegademiC; 02-14-19 at 11:33.

  5. #5
    Join Date
    Jan 2008
    Location
    Roaming
    Posts
    889
    Feedback Score
    0
    Quote Originally Posted by MegademiC View Post
    I may be able to perform hardness. Let me do some digging, but it would take a while. I could do 15T scale, but what you want may be too hard for us to test, and Id have to wait till Im at another facility.

    From my non-working knowledge of nitriding, hydrogen embrittlement is a non issue as no hydrogen is generated by the process. I thought it was a molten NaCN or KCN bath.
    The bolts and extensions should be in 58-62C range with a core in the mid 50s. I believe since the sections are so thin it must be tested HB then converted to "C".
    Companies selling the Nitride treatment are telling me one thing but what I am seeing is completely different. They all say Nitride treatment will not effect the torque of an extension on a barrel. Wrong ... found that in 2008 see the link to the video. I can hold a new barrel in my hand and just blip an impact and the extension screws right off.

    https://www.youtube.com/watch?v=1msz...ature=youtu.be

    The next thing they say is Nitride treatment only knocks down the hardness 1-2 pts. Again what I see is a much softer material dropping more like 8-10 points.
    Last edited by constructor; 02-14-19 at 12:15.

  6. #6
    Join Date
    Dec 2009
    Location
    Utah
    Posts
    8,799
    Feedback Score
    3 (100%)
    To get real data, you'll need to measure hardness before and after treatment.
    The number of folks on my Full Of Shit list grows everyday

    http://i115.photobucket.com/albums/n289/SgtSongDog/AR%20Carbine/DSC_0114.jpg
    I am American

  7. #7
    Join Date
    Jul 2006
    Location
    Oregon
    Posts
    4,630
    Feedback Score
    2 (100%)
    I have measured extensions to be softer after nitride. C scale.

    I did not cut a sample to get a core hardness. Surface hardness and depth were variables I would have liked to control but did not.

  8. #8
    Join Date
    Jan 2008
    Location
    Roaming
    Posts
    889
    Feedback Score
    0
    Quote Originally Posted by MistWolf View Post
    To get real data, you'll need to measure hardness before and after treatment.
    I have several hundred extensions that have not been nitride treated.

  9. #9
    Join Date
    May 2013
    Posts
    320
    Feedback Score
    8 (100%)
    Quote Originally Posted by constructor View Post
    Companies selling the Nitride treatment are telling me one thing but what I am seeing is completely different. They all say Nitride treatment will not effect the torque of an extension on a barrel. Wrong ... found that in 2008 see the link to the video. I can hold a new barrel in my hand and just blip an impact and the extension screws right off.

    Doesn't it depend on whether the extension and barrel are treated as a unit vs treated separately, then assembled/torqued?

  10. #10
    Join Date
    Nov 2010
    Location
    MI
    Posts
    3,516
    Feedback Score
    22 (100%)
    Yup.
    .
    .
    Quote Originally Posted by MQ105 View Post
    Doesn't it depend on whether the extension and barrel are treated as a unit vs treated separately, then assembled/torqued?
    Black River Tactical
    BRT OPTIMUM Hammer Forged Chrome Lined Barrels - 11.5", 12.5", 14.5", 16"
    BRT EZTUNE Preset Gas Tubes - PISTOL, CAR, MID, RIFLE
    BRT Bolt Carrier Groups M4A1, M16 CHROME
    BRT Covert Comps 5.56, 6X, 7.62

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
  •