Range Report  5.56mm AR, BC vs Speed in 16” barrel

Peter Laurvick

‘Merica!
Full Member
Minuteman
Jul 4, 2017
232
31
Jacksonville, NC
Hey all. I’m running an AR with 16” 5r 1-8twist barrel. Gun is generally very accurate but I have mostly used predator bullets (53-55gr VMax) and have very limited testing with match type bullets.
I have three different shooting competitions coming up next spring that either require or it’s a dang good idea to run tactical class gas gun. So I’m debating on what bullet, powder, etc to test out. Two of those matches will be well inside of 600yds, the third goes out to 1000yds but I’m not expecting awesome results that far with a 5.56mm.
I was thinking either some 77gr SMK, 69gr SMK or something like some 73gr ELD-M, 69gr Barnes Matchburners, etc. but I’m worried going too heavy a bullet will have negated results with a 16” barrel and the speeds I can get. It would be easy enough to do some side by side comparisons with a ballistic calculator if I know what speeds to expect. I’m hoping some of you here have done similar testing and save me some Components. What bullet do you run and what speeds are you getting?
 

kyzim311

Sergeant of the Hide
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  • Jan 29, 2020
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    Ohio
    I run a mild plinker load with 68 Hornady hpbt, 22.8 grains 8208xbr. Around 2650 fps out of a 16" barreled ar. It should be easy enough to push 77s that speed, but it is a data point.
     

    j-dubya

    A-Driver for Doobby’s Taxiola
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    May 10, 2011
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    Atlanta area
    At this time, the biggest factor would be what powders do you have, or have access to? If you have powders for the heavier weights, keep your focus on that. My pick for your use would be the old standby 77 Sierra. If you already have ELd’s that’s one thing during these times, but I personally would stick with a non-tipped projectile for competition or duty type use in gas guns.
     

    Peter Laurvick

    ‘Merica!
    Full Member
    Minuteman
    Jul 4, 2017
    232
    31
    Jacksonville, NC
    At this time, the biggest factor would be what powders do you have, or have access to? If you have powders for the heavier weights, keep your focus on that. My pick for your use would be the old standby 77 Sierra. If you already have ELd’s that’s one thing during these times, but I personally would stick with a non-tipped projectile for competition or duty type use in gas guns.
    Currently i use and have a stock Benchmark, IMR 8208xbr and Varget for anything I think is worth mentioning for 223/5.56. I know you can get good speeds with something like CFE223 but with the temperature instability I’m not excited about using it
     

    kyzim311

    Sergeant of the Hide
    Full Member
    Minuteman
  • Jan 29, 2020
    319
    245
    Ohio
    Currently i use and have a stock Benchmark, IMR 8208xbr and Varget for anything I think is worth mentioning for 223/5.56. I know you can get good speeds with something like CFE223 but with the temperature instability I’m not excited about using it
    IMR8208 xbr should give you decent velocity, so don't worry about cfe223. I loaded up to 24.1 in my application with no pressure signs, but the accuracy was at the lower velocity.
     
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    Alpine 338

    Lumberjack
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    Minuteman
    Jun 26, 2010
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    1,056
    NW Colorado
    I would shoot the 69-SMK's out to 600-yards if you don't have to deal with any wind, or there is no penalty for missed shots. If you have wind, then the 77-SMK's are the key to success. Varget, 8208, and other powders like Ramshot TAC and N540 also work well.