Bench-Talk

I bought a Remington 700 SS, 24" bbl 6.8 SPC last year or maybe the year before. Why? I don't know but it sounded like a good idea at the time. Well first impressions were what a waste, puny, underpowered etc. Then after letting it sit in the back of the rack for a year or so I found a renewed interest in seeing what it would really do, or rebarrel it into something worth while.

First problem was that all of the load data was for semi-auto-gas guns, no real loads at all for a Rem. bolt gun. After contacting Sierra(don't tell my boss) about  loads for the .277-135gr Matchking I was e-mailed loads that were designed for the Encore(well at least it's not a semi-auto). I went to the range(actually tunnel) and proceeded to start going for it. With seating depths of 2.450"(no they don't fit in the magazine) I started shooting. Well when I got to velocities of about 2680fps using Re10X I was getting scared. Easy bolt lift and round primer corners, lots of case volume left. This was just too fast for this little case. Even so at my final velocities using the 135MK I can pretty much match the venerable .308 Win -175gr MK (M118LR) in trajectory, and less recoil. Next I'll get actual pressure data and carry on up if feasible. If not I'll enjoy what I have now and maybe keep it around just for fun. But it does make me wonder what would it do in 6mm or .25 cal.?????????? Hey and there are some neat FB bullets available in those two calibers too!

Rory D. 

Rory, it's good to see you "out and about" again! Thank you for the insight - this one could be a real sleeper cartridge for the recoil sensitive (young/small-framed) deer hunters . . and why not, with decent bullets, a BR cartridge? Please keep us posted regarding your pressure findings! Oh, have you ever pressure tested the .30BR or, 30x47 [competition] type loads  - like the typical 42.5 Gr. charge of N-135 behind a 118 or, 125 Gr. bullet??? RG

Well, Ouch!

I checked the pressure on the sweet load. Ok ready for this, sit down, 71,000psi. While not crazy high, it is still high. I'd bet many BR setups are pushing the same if not more pressures. I think many are decieved by how the primer looks. On these loads the primer showed no signs of flattening and bolt lift was not feeling any resistance. Be careful!

If I had a 30BR piezzo barrel you know I'd be all over that. If only it was a SAAMI cartridge then we would get a barrel, any takers.

Anyway I have checked .308 Win and saw the same thing with primer flattening, although not to the extreme as the 6.8 cases.

RAD

Rory,

Thank you for sharing this info - I have often wondered about this!

Last week, while messing around with a 6MM DASHER (using 121 Gr. bullets), I  decided to "creep-up" on the "maximum" pressure via small increments (the powder was RL-15) - this via my old reliable (Borden TRUED) Time-Precision ALV actioned HV rifle. With each additional powder charge the chronograph  showed nicely increasing velocity - right up to the point where, with never a hint of difficult extraction, a case STUCK in the bolt-face recess! Naturally, when I removed the bolt and forcably parted the case, the primer fell onto the bench top . . . I never realized that the Time operated so "easily" - because of the relatively short bolt handle, I've always avoided "hot" loads . . .well, so I thought! ;) RG

I was wondering the same thing about the 30x47 pressures. 42.7 Gr of N-135 behind a 130 gr bullet seems like it should be a hot load but I dont see any pressure signs and have easy bolt lift. Rory, I always like to here about people testing things, especialy when they have the tools to do it right. Thanks for the info on your findings with your 6.8.