My 45-70 Load

[doubs43]

For many years I've used the same 45-70 duplex load in my 1875 C. Sharps Business Rifle with excellent results. I've recently bought a Marlin 1895 Cowboy rifle and tried to work up a little lighter load. The best I'd found to date is 32.0 grains of IMR-4198 with a tuft of Dacron polyester filler and the RCBS 300 grain GC bullet. But, I wasn't really satisfied.

Then I thought "What the heck, let me try my Sharps duplex load in the Marlin". I needed sight settings for this Saturday's lever action match anyway so when the sun broke through today - after many days of steady, cold rain - it was off to the range. My load is the same 300 grain RCBS GC design over 3.0 grains of WW-231 and 57.0 grains of AA-8700. (My 8700 will soon be gone and I'll start using WC-860 that is pulled down surplus powder. It's supposed to be usable with 8700 data.)

The following is my 150 meter target shot while seated over crossed stakes. The high shot was called when the rifle went off. The group is 2 & 3/4 inches C-C. My 1895 Marlin is pretty darned accurate IMO.

http://i70.photobucket.com/albums/i99/doubs43/1895%20Marlin%20CB/1895CBTarget150MetersFromStakes.jpg

[doubs43]

Good shooting:Fire:, 1 5/16th" group without the called flyer, and at 150 meters whatever that is in yards[smilie=1:.

Our range is set up in meters because we used to host IHMSA events. Twenty years ago they were popular and when a match was held, it took two days to complete. Now we shoot a couple of silhouette matches using Buffalo rifles for one (40 shots) and lever action rifles for the other (30 shots). They only take a few hours for each.

150 meters = 164 yards.

So far I'm really pleased with the Marlin 1895. It's proving to be more accurate than I expected.

[dualsport]

I've used similar loads in a Ruger #3 45-70, only 5010 and 860. Did you get the idea from Paul Mathew's book?

[doubs43]

I've used similar loads in a Ruger #3 45-70, only 5010 and 860. Did you get the idea from Paul Mathew's book?

I've been using this same load for nearly 20 years. I did get the idea for it from an article or book but I can't say it was written by Paul Mathews. It made sense at the time as AA-8700 was selling for less than $4 a pound as I recall. It also made sense that such a slow powder would burn all the way down the bore and keep pressures low. The 3.0 grains of WW-231 is a good igniter for the 8700.

Many years ago I chronographed this load and it was amazingly consistent with a single digit average variation in velocity. I wish now that I had written the data somewhere permanent.

At one time I owned a C. Sharps in 40-65 and adjusted the load for the smaller case. I used 2.5 grains of WW-231 and as much 8700 as the case would hold with a seated bullet giving some compression. The compression and a moderate (not heavy) crimp is needed for consistency. The 40-65 was very accurate but I allowed myself to be talked out of it. Another "wish I'd never sold it" story. :sad:

[Al57]

doubs, that is a fine group . Was it acheived by the factory Marlin iron sights ? Also, what do you feel you gain by the duplex load vs. just a slow powder with a standard or magnum primer ? Long time 45-70 fan here too, and my current load is a 405 gr. boolit on top of 32 grs. of IMR 4198. Runs about 1350 from my 22 " bbl and has proven to be quite accurate and a quick whitetail stopper . Regards

[doubs43]

doubs, that is a fine group . Was it acheived by the factory Marlin iron sights ? Also, what do you feel you gain by the duplex load vs. just a slow powder with a standard or magnum primer ? Long time 45-70 fan here too, and my current load is a 405 gr. boolit on top of 32 grs. of IMR 4198. Runs about 1350 from my 22 " bbl and has proven to be quite accurate and a quick whitetail stopper . Regards

I've added a Marble's tang sight because my old eyes simply can't use barrel mounted open sights any longer.

The duplex load fills the case and actually pushes the bullet back out about 1/16th of an inch after it's been seated and crimped. AA-8700 is so slow that even a magnum primer won't ignite it efficiently and leaves a lot of unburned powder grains in the bore. The 3.0 grains of WW-231 does a great job of ignition and leaves very few grains of powder in the bore. No filler is necessary and the consistency of the duplex load velocity was in single digits when I ran it over a chronograph.

I tried 32.0 grains of IMR-4198 with a Dacron filler (just enough to hold the powder in place) and it did well but I use the duplex load in my 1875 Sharps and staying with one accurate load in both rifles keeps it pretty simple.