Best barrel length for SBR, 10.5, 11.5, 12.5..?

[The Dumb Gun Collector]

I say go 10.5. If you are going short, you might as well go as short as you can reliably go. Much longer than that and I start thinking a 14.5 plus extended hider or 16 makes sense.

[Magic_Salad0892]

12.5 is the best. I have an LWRCi 12.7'' gun. It's amazing, especially suppressed. (You don't notice the .2''.)

I plan do on building an LWRCi M6 CQB-R 10.5'' variant though, eventually.

[Iraqgunz]

I have an 11.5" and I shoot it suppressed/ unsuppressed. Perfect balance between a 10.5" and a 12.5". YMMV

[TehLlama]

7.5" is too short - barring an application where you're trying to use it as a PDW, doesn't make much sense. 5.56 isn't very effective at that velocity, and even though OPS will cover cans on something that short, there's so little to gain over a 10.5"

I'd say 10.5" makes sense for mostly suppressed only - that's the route I'm going.
Like Iraqgunz mentioned, 11.5" is a great host for a QD can.
The strength of the 12.5" is the extended fragmentation range - but if you don't need it, it's hard to justify. That said, it's just an inch, and without a can on it that difference is hard to notice.

[Dump1567]

Buy and try.

I started with a Noveske 10.5 w/pig in 5.56.

Than picked-up a 7.5 Noveske Diplomat w/pig in 6.8 (I've read ballisticlly you don't want to go under 10" in 5.56).

I just picked-up a 12.5" BCM (Kino Configuration)
and added a Vortex FH. I like the longer handguards. Length is less than an inch longer than the 10.5 w/pig.

Here's a good read:
Q: Why BCM chose the 11.5" SBR over the 10.5"

http://www.ar15.com/forums/topic.htm...f=138&t=174764

12.5" BCM (Kino Configuration)

[Dolphinvet]

I have a 10" bbl. on my SBR with a SS YHM suppressor. A bit loud I think, but nicely balanced and it does handle well. I guess it depends on what application you're looking for, etc. I know you can get a thousand different opinions here on what is best.

To put it in perspective, as a doctor, it would be asking me what antibiotic is best. It really depends on what you intend to treat!

[Pappabear]

Buy and try.

I started with a Noveske 10.5 w/pig in 5.56.

Than picked-up a 7.5 Noveske Diplomat w/pig in 6.8 (I've read ballisticlly you don't want to go under 10" in 5.56).

I just picked-up a 12.5" BCM (Kino Configuration)
and added a Vortex FH. I like the longer handguards. Length is less than an inch longer than the 10.5 w/pig.

Here's a good read:
Q: Why BCM chose the 11.5" SBR over the 10.5"

http://www.ar15.com/forums/topic.htm...f=138&t=174764

12.5" BCM (Kino Configuration)

Great feedback and a great read from the BCM guy. I'll probably go the 11.5 or 12.5 route for my first SBR. Im also thinking a Vortex as opposed to the Pig. That Pig defeats the purpose of the SBR in general IMHO.

[TehLlama]

Iv you're considering the Gemtech G5 at some point in time, there is an SEI Vortex that has mounts for the G5 as well.

[Magic_Salad0892]

Does anybody know what the dwell time difference is on a 12.5'' vs. an 11.5''?

If it derails the topic, PM me.

Thanks.

[rob_s]

I think you need to back up a step and ask yourself a few basic questions, and once you've answered those questions your length issue will probably resolve itself.

1. Why do yo want an SBR?
2. What is the maximum distance at which you require you ammunition to perform as desired?
3. How Flexible is your ammunition selection (i.e. are you restricted to department or agency issued ammunition?)?
4. Do you intend to add a suppressor?
5. If so, do you know which suppressor you'll be adding?
6. If so, is it a QD suppressor with a mount and what mount is it?
7. etc.