I was looking at a AR today and the barrel was marked “B MP” is this the marking for Bushmaster?
Next qustion did they ever make a 26" barrel? I own a 24" AR and this looked longer then the one I have, but maybe it was just a illusion.
You don’t want anything that long anyway…
I wasn’t going to buy it I just never seen anything like that before.
We actualy spent more time making fun of it, saying it was the department’s new QCB upper for the M16s
Yes its a Bushmaster and yes thats the longest they go .
That’s a long barrel
I’m curious what the optimum length of a 5.56 barrel would be when considering nothing but maximizing velocity? Forget about handling characteristics and all that; just what length would give highest velocities without being so long that the drag starts overcoming the pressure of the expanding gasses?
I have seen a couple of articles where they started at 26 inches and cut off an inch at a time until they reached 16" but they did it on a bolt gun. There are too many variables with an AR to come to any meaningful conclusion. Weight of the bullet, propellant burn rate and location/size of the port will affect the results. I know it’s a different animal but the guys shooting 6.5 like 22" with +2 gas. The gains beyond 22" are not worth putting up with the longer length and weight.
True dat. However, when I said 5.56, I was assuming standard NATO ammo and not the infinite variations that handloading could introduce.
You may find this interesting.
Thank you! That was a VERY interesting article. I’ve never been to that website, though someone occasionally leaves a copy of Small Arms Defense Journal in the head where I work at Quantico.
I liked your other link also - Here, Kitty, Kitty! 