Duplexing .45-70 with WC872 + heavier bullets

[oldblinddog]

This is simply not true. Duplex loads can be safe and are needed for a clean burn with ultra slow powders like WC 872 in large cases like the 45-70. The Oneal - Keith - Hopkins crew did use duplex charges of powder, but ignited the charge from the front via a brass tube installed in the case. The OKH experience should not be conflated with duplex loads in general.

The OKH "duplex" was simply the tube, which was 1/2 the length of the case body. Being ignited in the middle of the charge, the ignition went both directions, hence the term "duplex". There was only one type of powder in the charge.

[KYCaster]

............Simply drop the igniter charge and then dump the main charge on top of it. For the 45-70 or the .43 Spanish the igniter charge is sufficient to remain in place when the main charge is dropped.

...............Buckshot

You mentioned using a drop tube when throwing the main charge into the rifle case. Where could I go to learn more on the subject? So far I have never used compressed loads and would like to learn since I just got 8lbs of 872 and 680.I really hope this is a typo!! WC680 is not the same as WC860!! DO NOT USE ANY OF THIS INFORMATION WITH WC680, YOU WILL DESTROY YOUR GUN AND POSSIBLY CAUSE SEVERE INJURY OR DEATH TO YOU OR OTHERS NEARBY! WC680 is a VERY FAST BURNING rifle powder similar to AA1680, not at all suitable for 100% density loads in large cases. PLEASE BE CAREFUL! Also how do you start to add the main charge of powder over the kicker so you don't move the kicker powder away from the flash hole?

Noted, the miss-type powder designation and changed to 860 in the original post. Good catch!

...............Buckshot

[iplaywithnoshoes]

My response may be a little late but yeah, I haven't noticed any issues with the kicker charge being displaced by the main charge. I used H50BMG which is a stick powder with very large, dense granules. If displacement had occurred whilst dispensing the main charge, it would have shown up on paper for sure. Therefore, these ball powders should not have any issues with displacing the kicker charge. Seeing that a smaller stick powder like 4198 takes up more volume per granule than WC872, there are certainly less concerns with the two intermixing. My 2 cents.

shoe