Velocity Comparison to barrel Length Testing on AR-15s

[SA Friday]

Before it's asked, "Why didn't you use XXXX ammo." Well, I didn't have enough 69gr loaded and I don't have M855 as I find it shitty at best. So I didn't add those to the testing. After analysis, I'm not sure they would have added much to the results anyway. What the testing would have really benefitted from was more shots per sequence, but this was fairly expensive as it was.

[Great-Kazoo]

Appreciate the write up and time spent testing. IMO for most applications, any 16" bbl should work for the average shooter.

[MarkCO]

This site has a good data set: http://www.ballisticsbytheinch.com/223rifle.html

[Madusa]

Good work! I did something not as intense as yours but it may add to your data. I started out with a 24" barrel (DPMS) with a 1-9 twist. With handloads of SMK 69 g /26g Winchester 748/CCI mag primers. I got average velocity of 3031 fps. Then I cut the barrel down to 18" and ran the same load to get 2932 fps. Also it should be said that these test were not done the same day and external ballistics may be a little different.

[vossman]

This is good shit. Thx for the work.

[SA Friday]

Appreciate the write up and time spent testing. IMO for most applications, any 16" bbl should work for the average shooter.

Agreed. After testing, I'm leaning toward the 14.5" being the optimal barrel length for overall short to mid range use. 16" is just more convenient due to NFA requirements.