155 gr bullets for 30 Carbine Blackhawk

[jski]

I’ve been working on developing a heavy load for my 30 Carbine Blackhawk but hadn’t working on it of late. But then I got a LabRadar for Christmas! So I took my Blackhawk out today.

I’m loading 11 grains of H110 with a 155 grain cast bullet. Fired 50 rounds and got an average of 1265 FPS. That actually exceeded my expectations. I needed to get above 1200 FPS with the 1:20 twist rate to maintain stability out to 50 yards.

Anyone else experiment with heavy loads for the 30 Carbine?

BTW, I didn’t see any signs of excessive pressure.

[PositiveCaster]

My big bore silhouette load for my .30 Carbine Contender was the RCBS 165 SIL boolit over 16.5 grains of RL-7 for 1500 fps. It was highly accurate out past 200 meters, but my barrel had the 1:10” twist. The velocity will be lower in your revolver, but it might work for you with the shorter bullet.


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[megasupermagnum]

327 federal, Accurate 31-148GC, H110. Accuracy started to go downhill just past 1300 fps in my 5" GP100. On another note, I now only use that bullet as a 144 grain hollow point, and that with 11.5 grains of H110 is the most accurate load I've ever tried in my Henry rifle. I never clocked it in the rifle, but I'm guessing it does close to 1450 fps. In the 5" GP100, it's right at 1200 fps.

All of my 327 guns, including the rifle are 1:16" twist.

I'm quite proud of how accurate that bullet turned out. It might be worth a shot in the 30 carbine, just specify a .311" body, and .309" nose.

[cwlongshot]

Awesome preformance!

I have some MP 314-140HP’s. Im really hoping my Single Seven cyl will be long enough for. I know my 32/20’s will appreciate the bullet but hoping my 327 does!!

CW

[megasupermagnum]

You will need to seat deep for the single seven. 1.490" is about the longest OAL you can use. It does hurt potential to seat that deep, but you can still get over 1100 fps. Try Bluedot. 6.5 grains gets me in the 1050 to 1100 fps ballpark when seated deep.

[jski]

I’ve been trying to duplicate the results found in Paco’s Long Range Load For the .30 Carbine Blackhawk.

[cwlongshot]

You will need to seat deep for the single seven. 1.490" is about the longest OAL you can use. It does hurt potential to seat that deep, but you can still get over 1100 fps. Try Bluedot. 6.5 grains gets me in the 1050 to 1100 fps ballpark when seated deep.

. I was making some dummies last night and I have a Lyman 311440 that drops 312/313 and powder coated is up to 318... Easily sized to 314. I have shot some from a custom H&R with a SMLE take off barrel and they shoot very well. They're deep seated as you advise but might work if they stabulize. Pile driver shape for a 30/32!!!

CW

[DonHowe]

I had a .30 Carbine Blackhawk 30 years ago. I loaded to .32_20 performance and enjoyed it very much.
One distinct memory involving that gun was firing a few rounds of military ball and seeing a huge muzzle flash despite bright early afternoon sunlight!

[jski]

Interesting some should bring that up: “small case capacity”. The 9mm usually has bullet weights that range from 115 to 147 grains. And yet:

.30 Carbine
Case capacity
1.3640 cm3 (21.050 gr H2O)

9mm Luger
Case capacity
0.862 cm3 (13.30 gr H2O)

The case capacity of the .30 Carbine is 58% larger! So of course the question arises: why is a 147 gr bullets appropriate for the 9mm but a 155 gr bullets inappropriate for the .30 Carbine?

[Outpost75]

Interesting some should bring that up: “small case capacity”. The 9mm usually has bullet weights that range from 115 to 147 grains. And yet:

.30 Carbine
Case capacity
1.3640 cm3 (21.050 gr H2O)

9mm Luger
Case capacity
0.862 cm3 (13.30 gr H2O)

The case capacity of the .30 Carbine is 58% larger! So of course the question arises: why is a 147 gr bullets appropriate for the 9mm but a 155 gr bullets inappropriate for the .30 Carbine?

#311440 bullet OAL is 0.79" so ratio of bullet length to diameter is 2.54 calibers/turn.
The 20-inch twist rate of the .30 M1 carbine barrel is 65 calibers/turn.

Typical 9mm 147-grain bullet OAL is 0.65" so ratio of bullet length to diameter is 1.8 calibers/turn
Typical 9mm twist rate of 10 inches is 15.4 calibers/turn.

Big difference in gyroscopic stability. A simplified calculation: https://bergerbullets.com/twist-rate-calculator/

[PositiveCaster]

Which has nothing to do with case capacity and everything to do with twist rate. While the OP’s revolver doesn’t have the option, with a 1:10” twist the cartridge has ample case capacity to produce over 800 ft-lb of energy. I’m sure the 9mm can’t do that - due to its more limited case capacity.



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[jski]

I must admit, it seems a bit boneheaded of Ruger to put such a low twist rate (1:20) in a revolver. Especially when that leaves a lot of potential on the cutting room floor.

[Outpost75]

I must admit, it seems a bit boneheaded of Ruger to put such a low twist rate (1:20) in a revolver. Especially when that leaves a lot of potential on the cutting room floor.

Ruger didn't design their gun to shoot handloads, but factory 110-grain carbine ammo.

[beagle]

I played with heavy loads in the .30 Carbine Ruger for a while. They work but they're right at the upper edge of the pressure envelope. Look at my article on Castpics, Cast in the .30 Carbine Blackhawk. I read Paco's article as well. I don't think he was able to do that with a stock .30 Carbine Blackhawk but with a couple of reloading tricks that don't involve modifying the gun, it can be done. I was able to do it with the 311440, the 30-150-F RCBS and the 7.62X39 RCBS as well as I recall.
As well as I recall, you have to achieve 1200 FPS or accuracy goes south due to the bullet going unstable. Here, you're playing with a fine line with balancing an acceptable OAL for the cylinder, a bullet that will chamber and will accept the powder charge to achieve the 1200 FPS without pressure signs and sticky cases.
There are several tricks to it. Read the article and you'll see how I approached a solution./beagle

[jski]

Evidently, ”the Army tried a heavy bullet in the M1 carbine, an M18 152gr FMJ. Even with the much longer barrel and higher velocity than a 7 1/2" Blackhawk, the M18 just didn't pan out”.

I’d really like to get some info on these heavy bullet tests.

[cwlongshot]

Evidently, ”the Army tried a heavy bullet in the M1 carbine, an M18 152gr FMJ. Even with the much longer barrel and higher velocity than a 7 1/2" Blackhawk, the M18 just didn't pan out”.

I’d really like to get some info on these heavy bullet tests.

The US Armys needs and requirements couldn't be farther away from what the general cast bullet shooter commenting here wants...

CW

[beagle]

The heavies are good shooters out to 100 yards and I'd have no remorse in tackling a deer sized animal with one. For normal plinking, target and varmint use, they hake a lot to put together are hard to carry and awkward to load quickly./beagle

[beagle]

The heavies are good shooters out to 100 yards and I'd have no remorse in tackling a deer sized animal with one. For normal plinking, target and varmint use, they take a lot of time to put together are hard to carry and awkward to load quickly./beagle

[jski]

327 federal, Accurate 31-148GC, H110. Accuracy started to go downhill just past 1300 fps in my 5" GP100. On another note, I now only use that bullet as a 144 grain hollow point, and that with 11.5 grains of H110 is the most accurate load I've ever tried in my Henry rifle. I never clocked it in the rifle, but I'm guessing it does close to 1450 fps. In the 5" GP100, it's right at 1200 fps.

Sounds like where I’m at: my best guess right now is between 11-12 grains of H110 for an optional heavy load.

[jski]

The US Armys needs and requirements couldn't be farther away from what the general cast bullet shooter commenting here wants...

Point taken!