Also posted this in the Competition Forum and here for added inputs..

I ordered a RRA NM upper last week. So what is the est way to break in the barrel? I have read that many different methods can be used. What say you? While we are at it anyone want to share some pet loads? Figure I'll be using 69gr HPBT Sierras for reduced courses but 77's for full course. I bought a pound of Varget last year to try in my 22-250 for groundhogs and it worked well. Do the 77gr Sierras fit in the magazine? Anyone have OAL data for these bullets? I have a good caliper. And a thousand rounds of LC brass.

Load of horse hockey to me.

Clean that barrel real good with solvent and a brush. Then go out any shoot it. Clean as normal.

Seat those Sierra 77s to 2.25" They were designed to be magazine fed.
Back them up with 23.5-24.5gr of that Varget.

do you have a swager for the primers on that LC brass?  .223 goes to 2.260IIRC(dont rely on this, I am not quoting a reloading manual) for magazine length.  not sure if the 77s will make it.  

and try some accurate 2520 or 2230 some time, the ball powder is incredibly easy to use in a powder thrower and trickler.

Quoted: do you have a swager for the primers on that LC brass?  .223 goes to 2.260IIRC(dont rely on this, I am not quoting a reloading manual) for magazine length.  not sure if the 77s will make it.   and try some accurate 2520 or 2230 some time, the ball powder is incredibly easy to use in a powder thrower and trickler.

No, will pick one up though.  I like the ball powders too for the same reason.  I am toying with the prospect of getting an automatic thrower and scale, I understand that extruded powders do fine in them...  I am being deployed for a month next week so I will have some extra dolars to play with when I get home.  Still debating the tuned RRA trigger or a Jewell as everything I read has them in a dead heat.. Plus I want a nice coat..

Don't load them to 2.26". They may not jam up in the magazine today, they may not jam up tomorrow, but someday they will jam. I've seen Sierra, Hornady and Nosler match bullets vary in length by as much as .016" in the same box.

Quoted: Don't load them to 2.26". They may not jam up in the magazine today, they may not jam up tomorrow, but someday they will jam. I've seen Sierra, Hornady and Nosler match bullets vary in length by as much as .016" in the same box.

Thanx for the heads up!  What about the OAL on 69's?

www.snipercountry.com/Articles/Barrel_BreakIn.asp