WC872 load data for 7mm Rem Mag?

[Poodleshooter]

As my stocks of H870 dwindle to nothing, I'm left with an 8# jug of this fine 20mm cannon pulldown powder to shoot up. The seller quotes H870 data as working well with this powder. Hodgdon of course predicts dire consequences if I load any surplus powder with H870 data. As I understand it, H870 was formerly "WC870". Given the usual military nomenclature,this leads me to guess that this $35 jug of WC872 burns just a tad bit slower than 870.
Does anyone have experience with it? I'm planning on a starting load of 70-73grs under a 140gr Winchester PSP,using WLRM primers and working up from there. Max using H870 is 79-80grs with a 140gr SP bullet.

 

[Chainsaw]

Poodleshooter,

I load a 140 Barnes X with WC 872 in a 7mm Remington Magnum A-Bolt rifle. I doubt that you can overload this case with a 140 grain bullet and this powder, as I got to 78 grains and quit there. I would have to use a drop tube to get more in the case. Pressure signs are non-existant but accuracy was 1/2MOA.

My 8lbs. of WC872 is from Pats reloading out of Ohio. The lot# is 45452

My load is:
78 (seventy eight) grains of WC 872
Remington case
CCI250 primer (Rem. 9 1/2M primer worked well also)
140 Grain Barnes X bullet

Of course YMMV----I'm interested in how you end up, so please post back.

 

[Poodleshooter]

Excellent! I should be quite safe. Oddly enough, I'm also using this in a Browning A-bolt (w/Boss). I'm not using a Barnes X though,so I should definitely be safe. If any bullet will cause overpressure with a load given for a generic bullet weight, the X bullet is it! I'm surprised you even got 78grs in there with an X bullet. Those suckers are long, and rather compromising of powder space. The terminal effects are worth it though.
I've got a mixed lot of cases, mostly Remington nickel plated,IIRC.
I'm not sure if I'll get to it this weekend or not. I'll post back with results. Did you chrono your loads? Were they compressed heavily?

 

[Chainsaw]

I used the load data out of Hodgdon's number 26 manual and it showed just the one load of 79 grains@ 3153 fps and a pressure of 46,800 CUP well below the SAMMI spec, for bullets of 139-140 grains.

I then started lower and with a micrometer kept measuring web expansion rings compared to the factory fired cases in the same rifle and could only get 78 grains and the bullet in the case without severe compressing of the load. I did notice you could gently tamp the load down slightly by tapping the case on the reloading bench surface so I wasn't real worried about severe over compression.

For some reason I never chronographed these loads. I'll look further in my notes and see if I can come up with something but it doesn't look like it now.

I am experimenting with the 7mmSTW and 120 grain bullets and this same powder as well.............Chainsaw