Page 4 of 4 FirstFirst ... 234
Results 31 to 34 of 34

Thread: Piston v. DI temp measurements

  1. #31
    Join Date
    Jan 2010
    Location
    Poland
    Posts
    1,688
    Feedback Score
    0
    Quote Originally Posted by Dave_M View Post
    This is intellectually interesting but thats it as overheating isnt a real issue outside of the internet.
    Overheating... no (unles you try to use DI AR15 as volume fire). But heat stress from cycles of heating to high temp and cooling down is. It gradually destroys internal structure of alloy reducing it's strength. It takes time and in range used semi-autos usually do not show at all, but in hard driven professional tools it can be a problem. Especially with shorter gas systems (carbine and shorter), when amount of heat transferred into bolt is much higher than originally designed by Stoner in M16 (actually if not chase for shorter barrel, adding pistons to AR15 design would never be needed).
    Montrala

    I'm sponsored competition shooter representing Heckler&Koch, Kahles, Hornady and Typhoon Defence brands in Poland, so I can be biased

    http://montrala.blogspot.com

  2. #32
    Join Date
    Aug 2008
    Posts
    1,663
    Feedback Score
    6 (100%)
    Quote Originally Posted by montrala View Post
    Overheating... no (unles you try to use DI AR15 as volume fire). But heat stress from cycles of heating to high temp and cooling down is. It gradually destroys internal structure of alloy reducing it's strength. It takes time and in range used semi-autos usually do not show at all, but in hard driven professional tools it can be a problem. Especially with shorter gas systems (carbine and shorter), when amount of heat transferred into bolt is much higher than originally designed by Stoner in M16 (actually if not chase for shorter barrel, adding pistons to AR15 design would never be needed).
    We have standards in metallurgy for the bolt/extractor/BCG for a reason. The current standard obviously stands up just fine. So some out of spec bolt made from dubious metal may be negatively affected by, 'overheating' but not your standard crop. This is what I was referring to, general theorizing about heat as opposed to any sort of hard numbers or tests.
    Dave Merrill
    Terrible Technical Writer. Awful Photographer. Lazy Instructor. Kind of a dick.
    Loves Tacos.

  3. #33
    Join Date
    Oct 2010
    Location
    Corpus Christi, Texas
    Posts
    260
    Feedback Score
    1 (100%)
    Good stuff. I have zero experience with the hk, but have played around with the osprey defense retro fit quite a bit. The barrel gets hot. I have wondered how much hotter than DI if any..? I pretty much figured out the piston retro fit is more of a novelty and not absolutely a necessity. I still have one on a 14.5 light weight bcm, and one on my 5.45x39 upper. I guess I was just bored, and wanted to do something different. They have ran lots of rounds just fine, so I see no reason to go back to DI. I guess I will run them til they fail, and slap a gas tube in.

  4. #34
    Join Date
    May 2011
    Location
    Kernersville NC
    Posts
    45
    Feedback Score
    0
    Why all this focus on metal fatigue? Lets focus on the difference 30 degrees makes on the lubricant that a carbon caked DI gun depends on to run properly, especially in parked BCGs. After running DI guns in the sandbox and in sub zero temperatures, I can say with all impartiality, the rifle that preserves lubricity best will be the more reliable one. On a two way range CLP is the last thing I want to screw with or think about.

Page 4 of 4 FirstFirst ... 234

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
  •