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Thread: Terminal ballistics-wise: Mk318 or M855A1?

  1. #21
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    Quote Originally Posted by ColtSeavers View Post
    My understanding after reading about this round off and on for some time now is that the pressure was dropped rather quickly due to burning out barrels, which was a point the Marines use to fight acceptance, and the only problem it has with current magazines is the tip is not presented quite high enough to not gouge the feed ramps of the barrel extension a bit.
    Even that was recanted. It started as a thread on Lightfighter from one guy with a specific issue, someone in the Army got a hold of it and took it way out of context and it blew up into something it wasn't. I'd fully accepted all of the reported issues about damaging the barrel extensions and/or feedramps until I was pointed to that thread and the OP saying that it never should've been presented that way.
    Sic semper tyrannis.

  2. #22
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    M855A1 pressure and velocity have been dialed back, yet was still within the 62,000 cup specified to meet both US performance and acceptance specifications and NATO Standardization Agreements. At its hottest it was 120 fps faster than M855.

    There are many, many web sites that use a photo showing an M4 barrel extension with old typewriter white-out applied for contrast showing "Chewed up" feed ramps. As stated above, this was a photo used in a powerpoint that was co-opted to show the ammo as being dangerous to issue (and total bullshit) because it "Physically damages the weapon."

    The new enhanced magazine simply has a Magpul follower with a slightly elevated bullet nose presentation angle for a higher straight-in feed rather than initially contacting lower on the feed ramp. They have a brown cerakote finish on the outside mag body.

    I have coached combat shooting teams and initial/basic rifle marksmanship training the last five years shooting M16A2s, M16A4s, and M4A1s (with both the old barrel taper and the Modification Work Order / new SOCOM heavy profile) and can reasonably say the M855A1 ammo shoots straighter and tighter to 500 yards than M855, and doesn't seem to be any better or worse for wear than the old ammo.

    Given the choice I'd rather shoot the new ammo than M855 or M193. I have no experience with the new MK318.

    69, 73, and 77 grain match ammo is for different purposes than mass-issue ammo for line Joes.

  3. #23
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    I would also be very interested to see any good documentation on taking the edge off of M855A1. AND any kind of study or credible evidence of it chewing up feedramps. I have always suspected that one pic that was so blurry and oddly showed damage only on one side. If feedramp / barrel extension damage is a real thing it seems like there wold be a lot of more believable pics out there. I'm not saying "it can't be true", I just want real pics and data if it is. My limited experience with the A1 is that on the terminal ballistics side it does several things well. "Match accurate" it has not been for me.

  4. #24
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    Thank you all for the clarification. I have only half heartidly kept up with m855a1 and apologize if I came across as trying to continue to spread BS.

  5. #25
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    Quote Originally Posted by ColtSeavers View Post
    Thank you all for the clarification. I have only half heartidly kept up with m855a1 and apologize if I came across as trying to continue to spread BS.
    I didn't take it that way, I was just part of the problem at one point so trying to correct that.
    Sic semper tyrannis.

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