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The military standard (MIL-C-63989 Rev. C) for M-855 is 3000fps plus or minus 40fps at 78 feet from the end of the muzzle with a 40 fps standard deviation. Which is also the NATO standard.
Lake City has 62gr M-855 listed with 3,020 fps. IMI has their 62gr M855 listed at 2817 fps. I have chrono'd LC M855 and got 3028 fps.
I have not chrono'd IMI M855 and I have a few boxes of it. I am planning to go to the range tomorrow and I will chrono a box to see what it is running.
Interesting results. I had 10 boxes of IMI M855. Lot #'s 00234/F and 00231/F that I have had for at least 3 years but I bought 5 boxes of each. I shot 10 rounds of each. One at the beginning of my session and the second an hour and a half latter at the end of the session so I would have a cool gun for first round on both. Outdoor range and about 50 degrees. Both gave just over 1 MOA groupings.
234/F gave 3 errors but of the 7 good readings they averaged 3132 fps, with a spread of 135, and a standard deviation of 30.9
231/F gave 1 error but the remaining 9 averaged 2958 fps, with a spread of 129 and a standard deviation of 36.8
So I guess it is crap shoot with IMI. Lot 234/F was higher than the MIL standard maximum velocity by 92 fps but it was within the standard deviation. Lot 231/F missed the bottom end of the Mil standard by 2 fps on average but while being within the standard deviation requirement it had a higher SD.
I am surprised there is that much difference between the two lot numbers. I bought both on sale within a few weeks of each other but I do not remember where but I think it was a big box sporting goods store. If I had not gotten the chrony errors the numbers could also be 5 to 40 points one way or the other with the velocity average.
____________________
Tony
NE ATL
'04 XLT regular cab 3.slo stepside
Semi retirement