16 lbs of WC857 Coming For 7mm RM’s

Joec7651

Handloader
Apr 7, 2019
519
137
I have 16lbs of single lot WC857 ball powder coming from Bartlett’s. At $13.17 a pound delivered it’s not the cheapest I’ve seen it but it seems to be the best price going at this time. I’ve done a good bit of research on it and it seems like it will do well with 160 grain and heavier bullets in my 7mm Remington Magnums.

It’s said to have a similar burn rate to H1000. I’ll start low and work up to pressure signs with a ladder test. At that point I’ll look for “flat” spots in the velocity curve to hopefully find an upper node to dial into. From the information I’ve found, pressure signs start to show between 76-79 grain charges in 7mm RM. Velocities have been stated at 2850-3150 fps in the 168-175 grain class in 7mm RM. I’m planning on starting at 65 grains and graphing velocity, increasing in .5 increments with 175 grain ELD-X’s and Winchester LRM primers as they are designed for ball powder.

Being a military surplus pull down powder I’ll have to keep meticulous records to develop a safe and repeatable load table for the particular lot. I found the MSDS for it, and it’s a double base ball powder with tin as a decoppering agent. Its said to be a cool burning powder, with steady predictable pressure curves in full, over bore cases at 93-100% densities.its supposed to have average to good temp stability. It’s not supposed to like being heavily compressed. It’s pulled from 50 BMG M17 tracer rounds and is said to be in the H1000 burn range and is faster than WC860. It’s recommended to use H-870 or AA8700 load data, then subtract 10%. I take that as to take lower mid range H-870 load data, subtract 10% from that and start working up to compile a safe load range for my rifles. I’ve done a good bit of reasearch on it and found it’s potential to be promising.

It’s coming in two 8lg jugs and I plan on blending the two containers in a rotary tumbler of my own design to ensure there will be no difference in burn rate of the jugs even though they are of the same lot. I am also going to add a small amount of Tubbdust to aid the already present tin in decoppering as it doesn’t affect burn rate. I want the 16lbs to be consistent throughout.

Please, if anyone has any experience with WC857 I welcome any and all your input.
 

Jimbeaux82

Handloader
Jan 6, 2011
359
25
Funny you should start this thread. I have an 8 lb keg of this powder which I bought about 10 years ago. I did 3 test loads for my 7mm Wea mag then and had plans this week to start experimenting in 270 Win, 30/06 and 7 mm Rem Mag.

Here are the test loads that I had run:

7mm Wea Mag
WC 857 70.2 gr 150 gr Rem CL 2644 fps
72.2 gr 2785 fps
74.4 gr 2844 fps

I shot a single round for velocity only. Not concerned with accuracy right now.

Will add in 1 gr increments from here and report the results when done.

I also have another milsurp powder which I will try, it is 7383. Please do not confuse this with IMR 7828.
It is said to be a military replacement for 4831. Mr Bartlett told me that he has successfully and safely used this in 30/06 and 25/05. Use 4831 data less 15%. I will be testing that a bit this spring as well.

Anyone else have any experience with this powder?

Jimbeaux
 

Joec7651

Handloader
Apr 7, 2019
519
137
I’m looking forward to working with it. It says it’s close to H1000, but the loads I’ve seen from those who have worked with it in 7mm RM look closer to Magnum. I’m sure actual burn rate will differ from caliber to caliber, rifle, and bullet weight. Also with it being pull down it’s likely from different lots to begin with. That’s why I’m going to blend the whole 16 lbs in a slow rotary tumbler to get the burn rate consistent throughout. Then I will work up loads knowing burn rate will be repeatable from load to load. No two jugs of pull down are the same, hence the blending.
 

Jimbeaux82

Handloader
Jan 6, 2011
359
25
Here are my results from the WC 857 tests. As always, you must be careful working up loads for your guns but this is especially true for milsurp powder which does not have much published data and lots vary much more than the canister powders we are used to working with. So with that said, here are my results.

Since WC 857 is supposed to have burn rates comparable to H1000 or RL 25, I chose the following calibers which had load data with H1000; 270 Win 130 grain; 30/06 180 grain; 7 Rem Mag 160 grain; 7 Weath Mag 150 grain:

270 Win, 130 grain bullet
59.0 grs 2478 fps
61.0 grs 2564 fps
63.0 grs 2645 fps (full case)

30/06, 180 gr bullet
58.0 grs 2131 fps
62.0 grs 2227 fps (full case)

7 Rem Mag, 160 gr bullet
64.0 grs 2408 fps
66.0 grs 2443 fps
70.0 grs 2634 fps
72.0 grs 2687 fps
74.0 grs 2804 fps SD=0 !!
76.0 grs 2866 fps SD=0 !! (full case)

7mm Weath Mag, 150 gr bullet
76.0 grs 2792 fps
78.0 grs 2879 fps (full case)

All velocities taken with Magnetospeed, 2 shots per charge weight. Did not shoot or record group sizes just velocity.

as you can see, I got near full speed velocities from both 7 Mags, especial the 7 Rem Mag 160 gr loads. Note the very low SD's albeit a limited number of shots (2)

270 Win is useable but powder is too slow to get anywhere near full velocities

30/06 I would list as not applicable unless under extreme shortages. I do not know anyone who would be happy with a 180 gr load that clocks 2227 fps.

Anyway these were my results and please use with caution.

My next milsurp workup will be a milsurp powder listed as IMR 7383 which is supposedly a military replacement for 4831. Not sure when I will get to it but it is on my list of projects.
 

frankm

Handloader
May 10, 2009
411
8
Looks pretty slow burning to me. I d be sure to use a mag primer and might try heavy for caliber bullets to get better performance. Especially in 270 and 06.

I bought a bunch of Jeff’s pull down ball powder 25-30 years ago ($8 a pound then!) and it was slower burning than his advertised rate also. It didn’t build pressure before the cases I was using it in were full and left a nasty, unburned film of black in my barrels.

Good luck with your excursion!
 

Jimbeaux82

Handloader
Jan 6, 2011
359
25
I used Rem 9 1/2M primers in the 7 mags and CCI 200 in the 270 and 30/06.

I realize that 150 gr for the 270 might get better results but didnt want to blow thru too many components on this test.

30/06 I would not use anything heavier than 180 gr in my hunting.

I know mag primers might give up to 50 fps more in with the ball powders in 270 and 30/06 but the tests I did pretty much showed me where the potential lies.

Might try these suggestions (heavier bullets and mag primers) if I ever decide to load up for my hunting.
 

FOTIS

Range Officer
Staff member
Oct 30, 2004
23,013
49
Jimbeaux82":22nn793b said:
Here are my results from the WC 857 tests. As always, you must be careful working up loads for your guns but this is especially true for milsurp powder which does not have much published data and lots vary much more than the canister powders we are used to working with. So with that said, here are my results.

Since WC 857 is supposed to have burn rates comparable to H1000 or RL 25, I chose the following calibers which had load data with H1000; 270 Win 130 grain; 30/06 180 grain; 7 Rem Mag 160 grain; 7 Weath Mag 150 grain:

270 Win, 130 grain bullet
59.0 grs 2478 fps
61.0 grs 2564 fps
63.0 grs 2645 fps (full case)

30/06, 180 gr bullet
58.0 grs 2131 fps
62.0 grs 2227 fps (full case)

7 Rem Mag, 160 gr bullet
64.0 grs 2408 fps
66.0 grs 2443 fps
70.0 grs 2634 fps
72.0 grs 2687 fps
74.0 grs 2804 fps SD=0 !!
76.0 grs 2866 fps SD=0 !! (full case)

7mm Weath Mag, 150 gr bullet
76.0 grs 2792 fps
78.0 grs 2879 fps (full case)

All velocities taken with Magnetospeed, 2 shots per charge weight. Did not shoot or record group sizes just velocity.

as you can see, I got near full speed velocities from both 7 Mags, especial the 7 Rem Mag 160 gr loads. Note the very low SD's albeit a limited number of shots (2)

270 Win is useable but powder is too slow to get anywhere near full velocities

30/06 I would list as not applicable unless under extreme shortages. I do not know anyone who would be happy with a 180 gr load that clocks 2227 fps.

Anyway these were my results and please use with caution.

My next milsurp workup will be a milsurp powder listed as IMR 7383 which is supposedly a military replacement for 4831. Not sure when I will get to it but it is on my list of projects.

Maybe closer burning rate to H869 or RL33?
 

Joec7651

Handloader
Apr 7, 2019
519
137
FOTIS":1964njt0 said:
Jimbeaux82":1964njt0 said:
Here are my results from the WC 857 tests. As always, you must be careful working up loads for your guns but this is especially true for milsurp powder which does not have much published data and lots vary much more than the canister powders we are used to working with. So with that said, here are my results.

Since WC 857 is supposed to have burn rates comparable to H1000 or RL 25, I chose the following calibers which had load data with H1000; 270 Win 130 grain; 30/06 180 grain; 7 Rem Mag 160 grain; 7 Weath Mag 150 grain:

270 Win, 130 grain bullet
59.0 grs 2478 fps
61.0 grs 2564 fps
63.0 grs 2645 fps (full case)

30/06, 180 gr bullet
58.0 grs 2131 fps
62.0 grs 2227 fps (full case)

7 Rem Mag, 160 gr bullet
64.0 grs 2408 fps
66.0 grs 2443 fps
70.0 grs 2634 fps
72.0 grs 2687 fps
74.0 grs 2804 fps SD=0 !!
76.0 grs 2866 fps SD=0 !! (full case)

7mm Weath Mag, 150 gr bullet
76.0 grs 2792 fps
78.0 grs 2879 fps (full case)

All velocities taken with Magnetospeed, 2 shots per charge weight. Did not shoot or record group sizes just velocity.

as you can see, I got near full speed velocities from both 7 Mags, especial the 7 Rem Mag 160 gr loads. Note the very low SD's albeit a limited number of shots (2)

270 Win is useable but powder is too slow to get anywhere near full velocities

30/06 I would list as not applicable unless under extreme shortages. I do not know anyone who would be happy with a 180 gr load that clocks 2227 fps.

Anyway these were my results and please use with caution.

My next milsurp workup will be a milsurp powder listed as IMR 7383 which is supposedly a military replacement for 4831. Not sure when I will get to it but it is on my list of projects.

Maybe closer burning rate to H869 or RL33?
I’m looking forward to seeing what it will do from my 26” X-Caliber barrel. He hasn’t got around to shipping it yet but it should be within the next couple weeks.
 
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