Duplexing WC860

[abqcaster]

Further reading of using other rifle powders in .357 seems to indicate, though possible you get unremarkable velocities and a very dirty barrel. That still has me curious about duplexing or using rifle primers.

[MT Gianni]

Has anybody tried duplexing (or even plain) wc860 in .357 magnum? I get a general sense from what I've read here and elsewhere that it may be possible, especially in a rifle. so much so I'm willing to try it my self, but am loathe to reinvent the wheel if someone here has already done it, and possibly not spoken up. I have looked around and only seen it used in 357 max, which is a different beast in that it uses rifle primers, but not all that different it seems. or heck lets just opine on it for "fun" like we do with every other topic.
-ABQ

I have seen lots of loads for 1680 in 357 Max but none for 860. This is finer than charcoal but with similar burn characteristics. Nice slow powder that needs to be appreciated for what it does well.

[NavyVet1959]

Has anybody tried duplexing (or even plain) wc860 in .357 magnum?

Well, just for curiosity's sake, I tried .50BMG and 20mm powders in a 10mm handgun once. From my study, I had convinced myself that there was no way that it could generate excessive pressure even with a full case of the powder and the bullet seated on top of that, but I had to prove it to myself. It was a fairly quiet round, probably because it was going so slow. It did not have enough power to even eject the brass. Recoil was very minimal.

To say the least, it's not an optimal powder for that caliber, but if you were EXTREMELY desperate and nothing else was available, it at least goes "bang".

I would have no qualms whatsoever with using a full case of WC860 in a .357 magnum from a safety standpoint. It's not anywhere close to being an optimal powder for that caliber, but if nothing else is available, it will go "bang".

[Hamish]

Think of it this way. The "normal" ratios for duplexing medium capacity rifle rounds (.303, 8mm, .308, 30-06) are between two and five grains of medium fast to fast powders (4198 or so on down) to clean it up or if you wish, really get it moving.

Scaled down to .38/.357, I sincerely doubt the one half to one grain of fast powder is even going to make much difference in a revolver of short barrel length, and I have to wonder why bother when a couple of more grains of fast powder and you've got your load.

That said, it's worth try ing if you've got the time and energy! Personally, I don't much care for the filthy nature of the stuff but it shoots well in the rifles so,,,,,,,

[abqcaster]

Think of it this way. The "normal" ratios for duplexing medium capacity rifle rounds (.303, 8mm, .308, 30-06) are between two and five grains of medium fast to fast powders (4198 or so on down) to clean it up or if you wish, really get it moving.

Scaled down to .38/.357, I sincerely doubt the one half to one grain of fast powder is even going to make much difference in a revolver of short barrel length, and I have to wonder why bother when a couple of more grains of fast powder and you've got your load.

That said, it's worth trying if you've got the time and energy! Personally, I don't much care for the filthy nature of the stuff but it shoots well in the rifles so,,,,,,,

I agree, regarding revolvers, especially considering the cylinder gap and other complexities beyond a short barrel. I was more interested in rifle performance. I appreciate your analytical thinking on the matter, Hamish. I wonder if, while linear scaling of the booster isn't practical, there may be a practical lower threshold, like 1-2gr of booster. I understand that with faster powders one only uses a few grains of powder and that achieves most short-barreled velocities, but slower burning "crossover-type" powders often require 13-15gr, so perhaps more of one of those as a booster. At this point I'm still thinking theoretically. Lots of good analysis and thought in this discussion, here. Thanks!

[NavyVet1959]

Given enough of a barrel length, one *could* look at it kind of like a multi-stage rocket. The faster powder gets it moving and starts the burn of the slower powder which then starts having more of an effect upon the acceleration of the projectile as it has started down the barrel.

I've wondered whether adding a bit of a slow .50 BMG or 20mm powder to a normal load that is still well below the maximum pressure allowed for the round would result in more gases produced and allow you to use non-optimal powders in guns that have gas operated bolts. For example, an AR chambered in .300 AAC needs a powder in a fairly small range of speeds to reliably operate the bolt. It's entirely possibly to use a fast powder like Red Dot and get the same velocity for a round, but the bolt will not operate due to not enough gas being produced. I'm curious whether adding a bit of one of these really slow powders would make enough of a difference to allow the bolt to cycle.

[Rattlesnake Charlie]

In one of Larry Gibson's posts he stated that using rifle powder like 4759 is better than the fast pistol or shotgun powders. You should read his post:
http://castboolits.gunloads.com/arch...p/t-28402.html

[Hamish]

I've wondered whether adding a bit of a slow .50 BMG or 20mm powder to a normal load that is still well below the maximum pressure allowed for the round would result in more gases produced and allow you to use non-optimal powders in guns that have gas operated bolts. For example, an AR chambered in .300 AAC needs a powder in a fairly small range of speeds to reliably operate the bolt. It's entirely possibly to use a fast powder like Red Dot and get the same velocity for a round, but the bolt will not operate due to not enough gas being produced. I'm curious whether adding a bit of one of these really slow powders would make enough of a difference to allow the bolt to cycle.

I don't know if it's been tried in an AR, but it has been tried by a few in bolt guns and SS's. Nobade refers to this practice as "reactive filler": http://castboolits.gunloads.com/show...eactive-filler

[rupe01]

As i have stated in other threads, I have duplexed WC872 (very similar to WC860) in many of the .30 cal and 8mm ammo rounds and even tried duplexing it in a .454 Casull Raging Bull with good results.....so i am sure that it would also work fine duplexed in .357 Mag too.

[KYCaster]

I have seen lots of loads for 1680 in 357 Max but none for 860. This is finer than charcoal but with similar burn characteristics. Nice slow powder that needs to be appreciated for what it does well.

Please don't confuse 1680 (WC680) with WC860. One (860) is a very slow burning rifle powder similar to H1000 or Retumbo, the other (680) is a very fast burning rifle powder or very slow burning pistol powder depending on the application, similar to Lilgun or H4227.

WC860 can be a good choice for large capacity magnum rifle cases and may be used in 357 Maximum with marginal success, but the same can't be said for WC680. It is close to ideal for the 357 Max, but try using it in 7mm Mag. and you'll get in trouble really quick.

Be careful out there.
Jerry

[9.3X62AL]

Powder Duplexing For The Dyslexic--film at 11!

[NavyVet1959]

Powder Duplexing For The Dyslexic--film at 11!

Yeah, I'm thinking a .50 BMG with a case full of 1680 might be worthy of a YouTube video...

OK... Someone with QuickLoad, satisfy our curiosity... What sort of pressures would a full case of 1680 be in a .50 BMG round?

[Wayne Smith]

Little story, years ago when I was in grad school I was shooting my 25-06 at South Coast Gun Club (since closed and built over, I understand) and a guy saw what I was shooting. He came up to me and asked what I was loading, I told him. He said "Have you tried any of that 860 stuff? It's so slow it burns all the way to the target!"
At that time it was branded and sold in 1lb cans. I still have one, I think.

[Nobade]

Yeah, I'm thinking a .50 BMG with a case full of 1680 might be worthy of a YouTube video...

OK... Someone with QuickLoad, satisfy our curiosity... What sort of pressures would a full case of 1680 be in a .50 BMG round?

You got me curious....
212,841 psi and 3285 fps loaded with a Hornady 750gr. Amax.

May be a tad too much.

-Nobade

[NavyVet1959]

You got me curious....
212,841 psi and 3285 fps loaded with a Hornady 750gr. Amax.

May be a tad too much.

Probably a pretty good chance for a bit of case separation...

I managed to get supposedly 167K psi on a 10mm once when I forgot that I had changed a powder measure from Longshot to Alliant Promo



So, what would that .50 BMG be with Bullseye?

[KYCaster]

Powder Duplexing For The Dyslexic--film at 11!

I also suffer from lesdixia.

Jerry

[iplaywithnoshoes]

Looking to try one of these slower ball powders for duplexing. I am familiar with the process but don't let want to commit to 6-10lbs of WC860. Does anyone know if I could replace replace WC860 with H50BMG to try some loads? Most of the powders I have are the appropriate burn rate as kickers. Also, would substantial pressure increases be evident using 500gr bullets in a .45-70?

[pworley1]

I use 4 - 5 g of 4198 depending on the case and bullet being used. Be sure that you ALWAYS use a compressed load.

[iplaywithnoshoes]

I use 4 - 5 g of 4198 depending on the case and bullet being used. Be sure that you ALWAYS use a compressed load.

Right, you don't want the two to mix in any way. Are you keeping the compression with a crimp or jamming the bullet into the lands? Is this with H50BMG? I am not asking for exact kicker weights.

[NavyVet1959]

Looking to try one of these slower ball powders for duplexing. I am familiar with the process but don't let want to commit to 6-10lbs of WC860. Does anyone know if I could replace replace WC860 with H50BMG to try some loads? Most of the powders I have are the appropriate burn rate as kickers. Also, would substantial pressure increases be evident using 500gr bullets in a .45-70?

Well, H50BMG is about $29 per pound and WC860 is $60 per 8-lb jug.

If you have 8 lbs of it, you will find *some* use for it.