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6/23/2009 3:56:12 PM EDT
A couple of questions have come up in preparation for a 308 build.  Will there be a difference between a 24 and 26 inch barrel in terms of accuracy or speed?  Does anyone have the dimensions of a barrel that they have had custom made?

What is a good option for a bolt carrier group?  I am looking for the best quality that is available.  If you have a source for where I could get one, please provide.
6/23/2009 4:43:51 PM EDT
[#1]
Yes, barrel length will effect velocity and ultimately accuracy. U may also want to consider the fact that a 24 or 26" gas gun is significantly longer and more unwieldy than a bolt gun of the same bbl length. That being said, in the specops community, our gas guns are 18-20", depending upon caliber, variant, etc. A good 308 gas gun will be expensive and difficult to build. Probably the BEST available without taking out a 2nd mortgage is the variant offered by Larue. I believe that is in the neighborhood of $2500, but don't hold me to it. I have the Remington R25. I added a Jard trigger, Magpull stock, DPMS free float rail, ergo pistol grip, and of course Harris bipod. I get equal performance to the SR25, and better than my new (issued M110)The gun retails for $1600, in stock form. Of course, once I added the mods, it is in the same $ category as the Larue. Note- I haven't even mentioned optics (more $).DPMS has a new variant that at present is only available to gov't entities, I havent used it yet. They also sell another model in the (I think) $1000 range, with a 24" barrel. I was not impressed at all with that gun. In short, I build A LOT of guns for myself and others, mostly AR's. I am also a qualified armorer. I steer people away from 308 builds, as they are a headache and very $ intensive, and its just easier to modify a store gun.
6/23/2009 5:07:28 PM EDT
[#2]
I hear your comments on the bolt vs. the gas gun.  I like the bolt better also, and probably always will, but I want to do something different here.  I pretty much already have all of the parts minus the barrel, BCG and gas block?  Do you know how long the barrels on the SR-25 are?  Since you are an armour, do you know what the dimensions on the barrels on the SR-25 are?  I don't recall seeing any spec info on the Knights Armament website.
6/23/2009 5:45:39 PM EDT
[#3]
From everyhting I have done, read and heard from very high-end gunsmiths and barrel makers, barrel length really doesn't have anything to do with accuracy.  Velocity is where you pay the piper.  For example, I have seen a guy shoot MOA at 300 yards with a 10.5 Noveske barrel shooting withhis elbows on the table as his rest.  That being said, I have read the most payoff you get from barrel length on a 7.62 is usually 24".  After that, the increase in velocity begins to deminish when the added length is taken into consideration.
6/26/2009 3:24:36 PM EDT
[#4]
Std SR25 barrels are 20" long
6/26/2009 3:27:15 PM EDT
[#5]
That is correct, it has been determined thru extensive research that 24" is optimum- however, different barrel lengths act different in velocity terms with different loads. Confused enough? Bottom line- u need to chrono to  get ground truth.
6/27/2009 4:39:35 PM EDT
[#6]
I have a Krieger 20" HB  on mine  from FA. & it shoots better than me . Build it , there is no diff. between a 308 type platform than a 5.56 . Just the size of the parts and in some cases just a little harder to get some parts . The 5.56 types have been around a lot longer ,so the parts base & availability with some parts is better. For now , but the 30 cal. is getting bigger every day .
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