Caliber debate. Platform is AR10.
Go!
I am studying an AR10 build but straight up 308 Winchester.
While both are based off the 308 Win casing and necked up with the 338 having a COAL shown as 2.820" and the 358 as 2.2780", the 308 it self is shown as COAL of 2.810". The 338 seem to only have rifle projectiles (limited styles and weights) and that could be what you are looking for with them. There 358 bullets range from handgun to rifle in styles so that could play into the various uses at intended velocities.
There are so many more bullet weights and styles on the 30 caliber than the 338 and 358... :D
Oh, there is a 308. I am am doing several builds. At least three, maybe five. So I may end up with both.
I am leaning towards 358 for the first "over 308" bore. Barrel is cheaper and lost more options in bullet selection.
Between those two, I'd go with the 358 Win. Purely on bullet selection.
For my, over 30 build, I'm looking really hard at this.http://www.tromix.com/375-socom-parts.html (http://www.tromix.com/375-socom-parts.html)
Theirs just something about having 375 Winchester power in an AR-15 platform. :P
I have a 338-284, and I quickly found out that most bullets seem to be designed for magnum case capacity. The 338 Federal has some power behind it, but its not in the same class as the 338WM or 338LM, which dominate the .338 bore. Smaller case capacity, compromised more by lesser velocity of short barrels might make the 358 a better choice.
Greg
Yea some of the guys on FB are venturing over to the 375 SOCOM Many were into the 458 SOCOM which is what I was studying and learning about...
I looked long and hard at the 375 bullets. Also the .416 bullets. I am a sucker for a high BC.
But, as I have a fair bit (30,000-40,000) of 308 brass around I figured I should stick with calibers that I can easily form from that brass.
I am leaning heavily towards the 358, for all the reason's mentioned.
I've been looking at doing an AR10 358Win for about a year now. Found a place in Sandusky Ohio to build it,I'm not interested in making it myself. There are some shops on the west coast that are making them. 35 caliber,in any rifle,never really became popular in the US. Because 358Win is an 'underbore' cartridge,my plans are for 16" barrel and treat it as a 'guide' gun. I've got dies,bullets(from 35Rem and 38/357 reloading) and been accumulating brass at gun shows. 358Win brass is relatively scarce and I've accumulated about 150 pieces.
I have landed on 358. Dies are inbound. I will order the barrel tomorrow probably.
It sounds interesting! If anyone cares, the .358 Winchester seems as if it would be more powerful and would overshadow any straight-walled .357" cartridge. Unfortunately the only autoloading successes in the nation are the .35 Whelen and .35 Remington. sadly the .35 claiber is neglected in this country. The Whelen needs a long action. At what range does the .358 Winchester "come into it's own"?
I just read a Chuck Hawks article about the cartridge. It seems even better than the .308 Win. for short-range (100-150 yd. range). This would work well in this "neck of the woods". (In a lot of "thick woods" out here in the West, tend to limit ranges). Besides, it fits perfectly in an AR-10 platform.
My barrel and reloading dies are on the way. I think I will order a couple of Noe bullet molds too. They have a 280 grain spire point and a 230/214 grain flat nose/hollow point. Both are gas checked.
the advantage of the 358 is the sheer versatility with a wide selection of projectiles and projectile construction. It's a great medium bore caliber.
That said I am a huge fan of the 458 SOCOM AR platform and a 308 in the Ruger Gunsite Rifle. Those two calibers can do it all.