I traded into a 6.8SPC, now what?

[piercedan]

Well, I did some trading and finally ended up with a 6.8SPC with a 1:10 twist. I've done some searching and reading and it looks like I need to have the chamber bored to SPC II specs. I don't know if it is already done, how would I check?

Also, I've ran into trouble loading the mags. I have six, and all six seem to jam the rounds up while loading. The tip of the ammunition keeps binding on the lip of the mag. I have tried going slow and tapping the mag back after each round, but a new round inserted seems to offset the round underneath and push it forward. Additionally, the rounds seem especially hard to insert. Nothing at all like 5.56. I disassembled and oiled the mags inside and out and then wiped them down. This may have helped a little, but is this normal?

I'm really excited about this new rifle, and look forward to getting to know its capabilities. Thanks!

[Guest 6.8 AR]

I have the reamer for those specs and you are welcome to use it, or I'll be glad to help you with it.

What brand of rifle and mags? The C Products and the PRI's have their own separate quirks or uses.

some say the Model 1 barrel is crap, and I agree, but they can be made useful with a little work.

Tubbs bullets can help with pressures due to the twist. You could always mess around with a Noveske

1-12 twist barrel and make your gun the cat's meow, but it's not necessary.

I'll be out of pocket except on here at a keyboard, due to having surgery, and will be back up to snuff around the

first of October. The reamer will make a big difference and you're welcome to it.

Also, does the upper have extended feedramps? Could be a problem if it doesn't. The mags might need a little tweaking,

also.

[piercedan]

The upper is a Doublestar and it appears to have M4 feedramps. I read up on the barrel twist, but it seems counter intuitive from what I've read about the 5.56 twist. With that, a 1:7 twist was recommended to stabilize the higher weight bullet. Am I understanding that wrong?

The magazines are PRI, which seems to be the next best thing to Barrett as far I as have read. They just seem too hard to load. In a combat situation, struggling with my mags to reload does not appear to be the ideal situation, to make an understatement.

Thank you for the offer to use the reamer. I think I'll be better to wait until you are back in action to help. You are the expert here (it's in you name), so I would take you up on your offer to help. :0)

Edited September 9, 2012 by piercedan

[Guest 6.8 AR]

No expert here, I just like the caliber, but thanks.

PRI and Barrett are the same mags for all intents and purposes. I think PRI makes Barrett's, not sure.

They are more clumsy to reload, but they are made of steel and heavier and the bullet is about as big

as you can get with the AR, notwithstanding the Blackout, which takes the std aluminum mag.

I'll let Gordon or someone else explain the twist problem, but most of the earlier guns that had the 1-10 twist

exhibited high pressure signs and were considered dangerous by some. It usually was a fix when the SPC2

standard came out, and I agree with that because that and the Tubbs bullets really made one of my 6.8's

shoot a lot better without the pressure problems showing up on the cartridges.

There was a company(Cardinal Armory) that made quite good 6.8 rifles and built a good reputation until the owner

received a batch of barrels that weren't quite right. It cost him his business, too. He was a nice guy, and even those

barrels were good with a little lapping done. I got two of his last barrels before he shut down and they turned out fine,

but several folks who bought his guns got bad ones and it ended up sinking him. His barrels were 1-11 twist, also.

Hey, it happens.