SBR Length

[meyer4589]

Getting ready to submit a form 1 for my first SBR. I’m have two uppers in mind one a 10.5 and the other a 7 inch. This will mostly be fired at ranges under 100 yards, mainly just something to take to the range and have fun with. Is the 7” going to be that much more impractical compared to the 10.5? How much velocity loss between the two?

 

[edwea]

If it's just to have fun with, how practical does it need to be?

 

[BIGE7.62]

10.5 seems to be the shortest most recommend.

 

[shootersix]

If it’s a 223/556, you should get the 10.5 inch, anything less and the bullet won’t stabilize and you could get baffle strikes.

I don’t have one, but the people I know who have one have told me this

 

[daddyusmaximus]

A 7.5 looks cool... but the blast is pretty damn severe. Not really that fun. You'll want to go between 10.3 and 12.5.
I've had 7.5, 9.5, 10.3, 10.5, & 11.5. I stuck with 11.5.

 

[OneBadV8]

I have a 7” .223 and it’s pretty fun. I threw a suppressor on it eventually. It’s more accurate than most claim. Perfect for home defense in my opinion

 

[Slow Hand]

11.5” is recognized as about the ’best’ all around 556 sbr length. I have a 10.5” and it does very well. I do have a 7 or 7.5” upper on a pistol but it has loved it’s whole live with a w2 conversion kit in it. I should run some 556 through it just to see how horrible it is! If you’ve not bought the upper yet, I would definitely recommend the longer of the Again, if it’s just for fun and doing mag dumps into trash piles, heck, go with the sooper showtay! The real reason the longer one is recommendEd is velocity and the 556’s need fo r a minimum velocity to really have a serious effect on human targets. If you get below a certain velocity it basically just pushes straight through and pokes small holes in flesh. Still not ideal for the said flesh, but the higher velocity does much more damage…

 

[I Invented the Internet]

A 7" 5.56/.223 gun is already impractical by its very nature so if I were building an SBR in this caliber, I'd consider 11.5" my personal minimum. Anything under that, it's 300BO or bust.

 

[Aszerigan]

The burglar after standing in front of your 7" AR...

 

[meyer4589]

Well thanks guys, I pulled the trigger and ordered a 11.5 upper

 

[Basher]

Good call, anything less than 10.3” is usually more frustration than it’s worth. I’m an 11.5” guy as well, as I find it just long enough that tuning it for reliability isn’t a major headache, but it’s still plenty maneuverable and fun.

 

[GunsCarsPlanes]

shorter than 10.5 is just for the hell of it, don't google the numbers they aren't encouraging