wc860 in 300 blk with 230+ gr bullet

[DrB]

Anyone ever try something like this with or without a "kicker" of fast burning powder?

I'm looking for actual experience/trial.

Thanks. DrB

[NavyVet1959]

I tried a case full of it in 10mm just for curiosity at one time. It goes 'bang' and the bullet came out the barrel. It would not eject the brass though. Very quiet round, little recoil. Figured I would have to be pretty desperate for powders be using it. Someone ran the numbers with Quickload recently and the pressure was very low on that test that I did. I would not be surprised if you couldn't also put a case full of this powder in the .300 AAC and it not exceed allowable pressure. Whether it would cycle the action on an AR, I don't know.

Case capacity for the .300 AAC and the 10mm are pretty close, aren't they?

At worst, you'll have to get a rod/dowel and hammer the bullet out of the barrel. An inconvenience, perhaps...

What barrel length are you using?

[Loudenboomer]

Hot magnum primers are your friend. I've not used 860 in a bore case ratio as small as a 300 blk. With heavy Boolits over a mildly compressed charge and fed 215 primers results have been good in the 35 whelen and the 308 win class. This powder is excellent in my .257 Wby threw the .338 lapua. IMHO using WC860 in the 300 bkl would be taking the powder way out of its realm. What are your desired goals? Do you require functioning on a AR platform?

[leadman]

I tried WC860 in the Ruger BH 45 Colt with a 300gr RFN boolit. I was surprised the boolit did not stick in the barrel. IIRC the boolit did not go more than about 50 yards before it hit the ground.

[Hamish]

DrB, use the Search for "Duplexing", be prepared to spend some time learning, at present I know of no "Sticky" on it. It has been discussed here since before here was even here,,,,,,

Short answer is yes, but you may have to use a "kicker" to optimize it.

[DrB]

I'm familiar with duplexing, looking for specific experience on the cartridge.

I have a bunch of wc860 (like a lot of folks) and was curious about the possibility in a heavy for caliber bullet/small case. I assumed a kicker of some sort.

Thanks for the reply.

Best regards,
DrB

DrB, use the Search for "Duplexing", be prepared to spend some time learning, at present I know of no "Sticky" on it. It has been discussed here since before here was even here,,,,,,

Short answer is yes, but you may have to use a "kicker" to optimize it.

[DrB]

Thank you, navy. I appreciate the reply.

16" cmmg, carbine length.

I tried a case full of it in 10mm just for curiosity at one time. It goes 'bang' and the bullet came out the barrel. It would not eject the brass though. Very quiet round, little recoil. Figured I would have to be pretty desperate for powders be using it. Someone ran the numbers with Quickload recently and the pressure was very low on that test that I did. I would not be surprised if you couldn't also put a case full of this powder in the .300 AAC and it not exceed allowable pressure. Whether it would cycle the action on an AR, I don't know.

Case capacity for the .300 AAC and the 10mm are pretty close, aren't they?

At worst, you'll have to get a rod/dowel and hammer the bullet out of the barrel. An inconvenience, perhaps...

What barrel length are you using?

[DrB]

I tried WC860 in the Ruger BH 45 Colt with a 300gr RFN boolit. I was surprised the boolit did not stick in the barrel. IIRC the boolit did not go more than about 50 yards before it hit the ground.

Interesting data point... a 300 blk with 247 gr bullet would be about twice the sectional density though.

In 45 caliber it would be the equivalent sd of a little under 600 gr bullet weight, right? I've read of folks duplexing wc860 in 45/70, so that seems plausible?

Which makes me wonder if a kicker could get pressure/confinement up enough for reasonable combustion. It's a silly enough idea someone ought to have tried it before.

[NavyVet1959]

Thank you, navy. I appreciate the reply.

16" cmmg, carbine length.

The question is going to be whether it will cycle the action / eject the brass.

I've tried Red Dot in a .300 AAC with a 10.5" barrel and even with what I thought was a hefty load, it did not eject the brass.

With the .300 AAC, even though it is a bottleneck round, there is not much difference between the neck of the bottleneck and the main body of the cartridge, so you're not going to get much pressure buildup like you would in a .300 Win Mag or some of the other cartridges that people have managed to reuse that .50 BMG powder in. As such, I suspect that you can put a full case of the powder under the bullet and not have to worry about it exceeding the SAAMI pressure for the cartridge.

Do you have a chrono?

If I was trying to develop a load for that powder, I would first fill up the cartridge with powder and then empty it out on my scale so as to see how much powder it can hold. I would load this and chrono it.
If that was not at an acceptable velocity, I would add 1gr of a fast powder to the bottom of the case right over the primer, tamp it down flat and even, and then add 1gr less of the .50 BMG powder on top of that. Basically, you are working up a load with replacing the slow .50 BMG powder a small amount at a time with the faster kicker powder as a sort of enhanced primer charge at the bottom of the case. I would use magnum pistol primers to start off since they are softer and will show pressure signs before a rifle primer would. Once they start showing pressure signs, you're starting to get up in the rifle pressure levels, so you might want to switch to rifle primers and take it a bit slower at that point.

[NavyVet1959]

Here's what Quickload says about a case full of a .50 BMG powder in a .45-70:

http://castboolits.gunloads.com/show...=1#post3048732

I have a very recent copy of QL, Version 3.8, and I can't find either WC872 nor WC867. I did however have listed Hodgdon H870, US 869, and 50BMG powders. I am not responsible for any misuse of this data - just presenting here for a comparison.

This data is NOT for actual use - just for comparing powders.
At 100% load density, using a 405gr cast bullet, OAL=2.550", 20" barrel length:
H 50BMG = 50.59gr, 925 fps, 770 ft-lb, max pressure = 9263 psi, 24% of the powder burnt
H US 869 = 53.08gr, 908 fps, 742 ft-lb, max pressure = 9032 psi, 24.7% of the powder burnt
H H870 = 51.46gr, 927 fps, 773 ft-lb, max pressure = 8946 psi, 26.4% of the powder burnt

on the other extreme, just for comparison at also 100% load density:
IMR Trail Boss = 16.79gr, 1129 fps, 1146 ft-lb, max pressure = 28208 psi (!!!)


Again, the data above is NOT for actual use - just for comparing powders.

Hope this helps... Post your results...

[leadman]

If you can find one of the first Accurate loading manuals from before Western bought them it has data for Accurate 870 in many cartridges with cast boolits. I have used this data in several cartridge with WC872 and the charges were close to identical. WC860 that I have seems to be just a little faster.

[DrB]

Thanks navy, leadman.

While I've read a lot on duplexing I've not had a reason to try it.

Smokeless powder unlike black is extremely burn rate dependent on pressure. If you fail to achieve sufficient pressure you won't burn the powder efficiently... I've read/corresponded with folks who managed to work 50bmg in 45/70 duplexing.

I have always wondered, however, when folks say the bore is mostly emptied of unburnt powder after so much kicker if they weren't just blowing out the unburnt powder more than consuming the slow burning powder.

I do have a chronograph. Since it doesn't appear someone else has already done the experiment, I guess I'll try to get the round tuit.

If I set up a vertical range over a sand bucket in the shop I guess I may also be able to resolve my burnt powder question.

[madsenshooter]

I've had some success in 6x45, but that little 80gr bullet is a far cry from your 230+gr 30 cal. When you get up to the energy and temp that a 50BMG primer delivers, the powder burns. I got very low SDs too.

[NavyVet1959]

I've had some success in 6x45, but that little 80gr bullet is a far cry from your 230+gr 30 cal. When you get up to the energy and temp that a 50BMG primer delivers, the powder burns. I got very low SDs too.

My experiment with a 10mm and even a magnum primer was entirely *underwhelming*.

I didn't try a kicker powder with it since I was just curious *how* underwhelming it was going to be. My rough calculations had convinced me that it would be rather mediocre at best, so I didn't even bother setting the gun up for being able to remotely pull the trigger. It was a data point, nothing more. From what I've been able to gather it does not appear to be even *possible* to load enough powder in a straightwalled case to get the pressure where it needs to be for these powders to operate at their intended pressures. You just need more ignition (arsenal primers or a kicker powder), possibly combined with a bottleneck cartridge.

[PewProfessional89]

I have duplexed IMR7383 with BR-5 (Bartlett's equivalent to Unique) for 300 blackout and have got it to accurately shoot and cycle my AR-15 with Lee 230gr. cast and coated boolits. Some with standard deviations of less than 3 fps. Here's a link to the video I made. https://www.youtube.com/watch?v=EdxzWY3_o0g&t=277s

I have went as far as 106% case fill and have had no signs of pressure. That being said, I am not liable if you blow yourself up. I have not duplexed WC860 yet, but plan to try it in the future.