Talk to me about 300 BLK supers

[Ian]

I cast, checked, and powder-coated some 311316s and have aspirations of seeing how fast the can be made to go with accuracy. Sort of a ".30 Carbine improved", maybe +150-200 fps. With 115 grains of bullet.

Powder of choice according to Quickload seems to be H110/WW296 (big shocker there), 100% load density giving near maximum pressure and velocity. Almost 2300 fps predicted.

From my 7" ROT AR barrel that will be about 236,000 RPM.

Is this idea doomed, or has anyone here tried something like this?

 

[RBHarter]

I'm going with probably not going to work out well .
However with the eternal optimism of Love Life "try stuff see if it works" .
I might suggest HT Lino .

 

[Joshua]

You’re not allowed to spin that fast. You will get a ticket if you go over 125,000.

 

[fiver]

meah run it in your puny 1-8 rotator.
I might suggest some 4227, but I know you got the 110 your trying to burn up.

 

[Ian]

I figure go for broke, if it works at all in the 7 it will be even better in the 8s. How's about air-cooled wheelweights at 13 BHN or so? There's gotta be a failure point somewhere,, I bet I find it.

I was thinking about dumping all that W296 off on Rich when he was here a few weeks ago but decided there maybe, might, almost could be a use for it in the BLK. If all else fails I got a few boxes of Sierra 130 HPs for the treinta-treinta, might get 1900 out of those from the BLK and they'll expand at that speed.

 

[Spindrift]

I can’t contribute any experience with the BLK. But actually testing «doomed ideas» is interesting, as new knowledge might emerge. Go for it! If anyone can make it work, it’s you!

 

[CWLONGSHOT]

I figure go for broke, if it works at all in the 7 it will be even better in the 8s. How's about air-cooled wheelweights at 13 BHN or so? There's gotta be a failure point somewhere,, I bet I find it.

I was thinking about dumping all that W296 off on Rich when he was here a few weeks ago but decided there maybe, might, almost could be a use for it in the BLK. If all else fails I got a few boxes of Sierra 130 HPs for the treinta-treinta, might get 1900 out of those from the BLK and they'll expand at that speed.

Those Sierra 130 HPs COME ALL APART on critters for me at that speed! I wont use on deer anymore. OK on smaller critters

BUT, they are also flat some of the most accurate for me!!

(SPEAKING CAST) I have yet to get any real accuracy past 1500fps ish. Shooting Steel inside a couple hundred... OK. But every time I have tried accuracy just fell apart. I trued 100% lino bullets to 20:1. Powder coated and Lubed both hard and soft.

My plinking load is 3031 and a LEE 312-155-2R @ about 1500fps. I have shot most from my bolt. But worked my shorty (made for subs) well Enough too.

Same gun shoots this @ 100 yards with Jacketed bullets that it likes.



Good luck!

CW

 

[popper]

I get 2150 from 145gr GCd in 1:10 carbine. Also got them to stay in the group (even though I posted the ballooned base - hornady case IIRC) from the 1:8 pistol. Lots are getting HV with the 110 Vmax so it will depend on alloy (add some Cu, size just above bore).

 

[fiver]

the V-max will do it ~meh~ but the nosler varmageddons are outstanding pushed with 110 or 2400.

AA#-9 has worked with the rcbs silh. bullet at around 15-1600 or so, no problems, and Josh's 300BO-140 I had him cut for a normal 30 cal rifle [then lapped it a titch more anyway] works in the Ruger just fine.
but I haven't really tried pushing it nor the 311359 too much.
the 359 may or may not chamber well [or at all as in the case of my AAC, at least not without more gyrations than I care to perform] depending on who made the rifle, but I bet even with that pointy nose it'd take some heat.

 

[waco]

I have a couple boxes of those 110gr Varmagedons. I have yet to try them in my RAR 300blk. Have never shot a jacketed bullet in that rifle now that I think about it.

 

[fiver]

shouldn't that have been named the RSAR?

 

[waco]

What’s the S for?

 

[popper]

18gr H110 behind the 110 Vmax = 2250 fps from carbine. Seated about 1/2 base into the neck IIRC. Problem with 110gr cast is seating depth, reason I haven't gone below the 145, fill the throat and still have some ogive in the bore. I've shot 150gr SPP hornady from both (1:10 & 1:8), same load, same accuracy @50. Ran the 145 PB PC to 2150 chrony'd and near MOA @ 50, close@ 100. 1% Cu, 4% Sb.
This is the interesting one, carbine @ 50 with HJ100gr hornady! Seated way out too.

 

[Ian]

The 311316 is basically a semi-wadcutter with a short nose, it has a sturdy driving band out front which pilots up really nicely in the throat when almost two-thirds of the bullet is in the neck.

 

[Kevin Stenberg]

Ian like your avatar states. You are a Notorious Member on our site. I have been looking for a logical reason for me to own an AR in 300BO. An your opening post gave me one.
I have always looked at the BO in terms of a hunting firearm. An i have 30/30's that are equal to or better than a BO. But in your wisdom you pointed me to think about the BO as an improved 30 Carbine. An i don't have any of those. An i really could use one.
I knew if i looked long and hard enough i could find a reason to own one.

 

[fiver]

semi= S.

Kevin if you think of it more in terms of damn I wish my 357 could do that, oh wait it can, oh no it really can't, well sort of,,, your a bit more on track.

 

[popper]

Kev - you do need one!

 

[Ian]

You need one. And a suppressor. You're welcome

Fiver, I have that Ace 140, casts .300/310 and checks fit beautifully. Downside is it's 157 grains dressed, wish it was shortened one band to make it closer to 125.

 

[RBHarter]

Just as glad you didn't dump it on me .......I have 2# and nowhere to put it .......

As close as I got to BO was a PP 200 gr x39 1700 fps on a full case of 4350 at mag length . Bumped out to single feed just to the bottom of the neck 25(?) gr gave 1800 fps . The barrel at best was grossly over sized and chambered to match . It would chamber a 323-175 2R seated to the crimp groove . .320 throat .316 grooves it was really more a n 8×57 I barrel than 7.62 ...... .310 to .317 was a perfect fit .

 

[Bruce Drake]

18gr with a lyman 311359 at 120gr total weight with gaschecks and lube. great load for this little cartridge and yes, a M1 carbine load with a bit more pop.