Ilove SBRs and I was wondering if anyone has put together a AR type weapon in .308 with say a 12 inch BBl?, And what are the pros and cons. I like DSAs FAL with the 13 inch but I would rather stick with the AR platform. Im wondering if it will feed, cycle OK, or if it would just beat the hell out of the weapon?also this would be a semiauto. Any help or info from you Guys would be GREAT. Also this weapon would be used with a Suppressor alot.
Thank You In Advance For Your Replies,
And Best Regards To All.
Chefgun.

I'm not sure if this will help, but I have an HK51 .308 with an 8.3" barrel. The recoil is actually less than with a 16" HK91 barrel because so much more velocity is lost compared to weapon weight lost. I would assume then that the weapon gets beat up less as the BCG is moving at a lower velocity. Functioning was not affected, but the HK uses a competely different operating system than the AR. I think you might have a little trouble with getting the correct gas pressure because IIRC most of the .308 AR's use a mid-length gas system when a carbine length would probably be better for a SBR.

Ammunition for the naysayers: When I shoot quality (Hornady TAP) ammunition through the HK51, muzzle flash is not significant and accuracy is very acceptable. I am able to shoot 3.5-4" ten shot groups at 100yds prone using standard iron sights. It is VERY loud, though, and muzzle blast is significant.

their have been 10.5 inch barrels on the ar10 platform with no problems and somewhat suprising accuracy (1 moa)

I'm no expert but I would look for a 6.8 SBR before I went to a 308 SBR.  And even then I would be looking to Noveske for the 308 SBR.  I have a 24" 20" and a 18" AR-10.  IMHO the 18" is a short as any non-operator in theater could expect to actually use.  If it's cool factor check out the Leonidus project from Noveske.  Dosen't get much cooler than that.  If you really wat to shoot the thing look at 18" to 20" Lots of utility and some solid ballistic performance outa a wide range of bullet selections.  

Even on a 308 SBR dont expect a light weight easy handling weapon.  They are heavier and slower to aim in tactical situations.  That was the original statement for the 6.8.  Same size/weight of 223 w/ more punch.  My 2c.

Oh, but they (7.62 SBRs) are fun.