50 BMG powder for CBs?

[FAsmus]

Gentlemen;

There is a possibility that I may receive some quantity of the slow stuff, surplused out of an estate sale as nearly worthless.

Now, I've messed around with things like H870 with CBs in the past with mixed results but this acquisition (if it happens) has possibilities for rather a lot of material designed for the 50 BMG case and I wonder if any of you indefatigable experimenters have ever worked with such a propellant in your regular sporting rifle chambers? ~ Safe, successful loads mind!

And! This may be pushing the envelope for the forum but I have heard rumors that compressed duplex loads of the slow stuff + a "primer" load of something like 700X next to the primer have worked out. Has anyone tried this?

Good afternoon,
Forrest

[redneckdan]

I have done significant work with it in several chamberings from overbore to straight wall. The recipe for success is a small kicker of fast pistol powder over the primer with a full case of WC860 with slight compression under a heavy for caliber bullet. I get very clean burn and excellent accuracy. This is actually my powder of choice for use with my 400gr 375 H&H bullet. I have not tried this with the big fifty yet.

[TonyM]

Would anyone recommend this kind of load development for a 338 Lapua Mag?

I plan on shooting 250gr SGKBTHP's... using Lapua Brass

So far, I have a pound of Rotumbo to play with (Still waiting for the upper to ship, so I'm just sourcing the other goodies right now).

I've heard of this kind of "Wildcatting" before, but never really got that much into it because I've never had a need to. I would be interested in it if there is much of a benefit over conventional single (Or simplex I guess) powder charges.

[Aaron]

Tony,

You will not need duplex loads in a 338 Lapua. You should be able to get full pressure/speed from these slow powders and that bullet.

Aaron

[wiljen]

yeah I wouldnt use a kicker in the 50 either as wcc860 was/is a 50bmg powder as is.

[redneckdan]

I 2nd what they said. The less bottle neck the more kicker was required to get a clean burn.

[FAsmus]

Redneckdan;

Thanks for the reply.

You say a "kicker" for the loads - that is what I've picked up too. The question is, how much of a "kick" would be indicated, say, for a 30'06 and a 220 grain bullet?

The "Big Fifty"? do you mean the 50/90 SS? Interesting if so because I happen to have a 50/90 SS that has proven itself at the 1000 yard match a couple times. What do you think? About 110 grains of 5010 or H870 under the 700 grain bullet?

Good morning,
Forrest

[wiljen]

Having tried wcc860 in the 45-70, I'd say the 50-90 will need a bit of a kicker charge to get it going. The big straight walled or mild taper cases don't seem to get complete burn without doing so.

[redneckdan]

Redneckdan;

Thanks for the reply.

You say a "kicker" for the loads - that is what I've picked up too. The question is, how much of a "kick" would be indicated, say, for a 30'06 and a 220 grain bullet?

The "Big Fifty"? do you mean the 50/90 SS? Interesting if so because I happen to have a 50/90 SS that has proven itself at the 1000 yard match a couple times. What do you think? About 110 grains of 5010 or H870 under the 700 grain bullet?

Good morning,
Forrest

Big fifty I mean the 50 BMG. I think that WC860 would work well in your 50/90. For cases like the 375 H&H or 45-70 (minimum to no taper) I go with 9-10% of the charge weight in kicker. My load for a 450gr paper patch in the 45-70 is 5 gr of red dot and 50gr of WC860. I went for about an 1/8" of compression on bullet seating and it burns very cleanly.

For the .30-06 (my work up is with the .30-284, pretty much the same thing). I went with 5-6% of the charge weight being red dot. The bottleneck of the case helps build pressure and get a complete burn.


Load this stuff like black powder. In a straight wall case you can't get enough in there to get over pressure. See how much powder fills the case of your 50-90 and weigh it. Then take about 6% of that weight and use that as your starting kicker charge. Figure out how much WC860 will will the rest of the case and that is your main charge weight. If the burn is not clean enough increase the kicker and lower the main charge weight to adjust to maintain that approximately 1/8" compression.

[swheeler]

In 06 you won't need a kicker with a 220 gr cast bullet

30-06 200 gr lee cast, IMR 5010-50.0=1770 fps,60.0 gr=1968 fps
same bullet, WC860 55.0 gr = 2009 fps

Different lots of same powder number can and will vary a LOT, pun intended. Up to 200 fps with different lots of 5010 and 872 in same loading same cartridge.

[wiljen]

One thing to add to Dan's comments, find the amount of 860 that will sit on top of the kicker charge and result in about 5% compression so the kicker charge doesn't wander away from the primer in transport. 100% fill will still allow movement of powder if dropped, shaken etc. By loading to 105% the compression will keep everything where it belongs.

[FAsmus]

Gentlemen;

Thanks for all the in-put.

At this time the powder is somewhere in-transit and I don't even know what the identification numbers are yet. ~ I used "5010" and "H870" as references as they were the slowest powders I have burned so far. I don't really know what I'm getting here but things being what they are I've always thought that some way can be found to use pretty much anything with a little careful testing and guidance from others who have been there already.

When things come together I'll post results here and we can all share.

Good afternoon,
Forrest

[Junior1942]

For 45-70 I load WC860 like I load Pyrodex--lubed felt wad and slight powder compression and medium-heavy crimp. I get circa 1150 fps w/500 gr bullets and 1.5 MOA easy. I got lots of unburned powder until I increased the crimp. ATA is in two Handi barrels.

[turbo1889]

For an "ignition booster primer assist" charge powder I have been using primarily Alliant Reloader-7 powder with mil. surp. 50-BMG ball powders for cast boolit loads in 7mm-08, 7x57, 308, 30-06, 7.62x54R, 303-Brit, 8x57, 8mm-06, etc. For the plain base boolit loads I have been filling the case up to the base of the shoulder with the 50-BMG powder and then filling it up the rest of the way with Cream of Wheat (COW) that serves as a flowing granular filler that works as good or better then a gas check and lets me push plain base non gas checked boolits at energy levels that would send most people scrambling for a GCed design at the very least if not consider the load only achievable with accuracy and a clean bore with the use of a jacketed bullet.

Long story short, R-7 is giving me the ignition boost I need and is much less sensitive to how much I use then all the fast burning pistol powders. With a duplex or triplex load set-up the difference between using one grain or two grains of a fast burning pistol powder as the ignition booster charge can be the difference between a good load and a high pressure load that overstresses the boolit or in the worst case scenario overstresses the gun !!! I’m much more comfortable with R-7 since just using a couple grains as a standard ignition booster charge has been the ticket over a large range of case sizes and volumetric capacity to bore cross sectional area ratios and has consistently given me excellent ignition without giving me any “interesting” loads so far. Interesting, as in a little too close to maximum jacketed boolit level pressures for my taste and pushing a cast lead boolit of 20+ BHN to hard and putting accuracy in the dumpster in short order and goobering up the bore with lead. When I experimented with using the fast burning pistol powders as ignition boosters I did have a few of those with only a small change in the booster charge level.

I have also used IMR-4227 as a booster powder as well but not with cases that have a large case capacity to bore diameter ratio like the 7mm-08. And not for igniting 50-BMG ball powder but rather for stuff with a smaller case capacity to bore ratio like the 7.62x39 with faster burning rifle powders that are still slow burning for the cartridge like 30-06 burn rate powders in the 7.62x39.

[FAsmus]

Turbo1889;

Thanks for the detailed information ~ all quite logical & understandable.

And! It just so happens that I bought a pound of Re7 the other day; things are coming together.

Good morning,
Forrest

[MT Gianni]

There a re a few loads for surplus powder on Castpics. I have used 860 & 972 in 30-06, 280 Rem. and a few more without a kicker if you have heavy boolits for the bore.

[swheeler]

FAsmus; take a look at the thread "Hogstooth first post" under cast bullets, AA8700 and WC860 are kissin' cousins for powders, results speak for themselves.

[htate]

There are lot of different 50 BMG powders and a few 20MM to boot. WC860 works really well in my 505 Gibbs (150 grains, 600 gr cast bullet and no duplexing). I get about 2100 fps. 5010 won't give me a complete burn or good velocity no matter how much I use. WC 872 is my go-to powder for full house 264 WM with 140-160 gr bullets and 300 Wby with 200 gr jacketed bullets. I also have a 550 Magnum which is basically a 55 caliber straight wall case and I can't get any of them to work well in that one. I guess I'll have to try some R-7. I never was willing to go the Bullseye route because I knew how fast things could go wrong. Glad to have learned something today; thanks!