I am working up a load for my Winchester 86 in 45-70 and having quite a time geting something I like. I am locked into a 405 grn RNFP bullet cast with a lyman mold. I load with a good roll crimp and Win large rifle primers. my goal is to find an accurate load in the 1250 FPS range. I am currently using IMR 3031 and finding that is is very inconsistant. I have tried 36 grns of 3031 and was getting around 1200 fps with a wide diference in velocity from shot to shot. close to 50 fps SD. I will shoot 3 shots and get the following velocities 1150 1190 1230 So I bumped up to 37 grns an got 1230 1250 1300. As the barrel warms it seems the velocities het higher.

If I reduce back to 36 grns of 3031 and switch to magnum primers will I get more consistant velocities? I was loading 5744 and a cotton buffer and the velocities were very consistant <8fps deviation from shot to shot. If I can't get the 3031 to perform I will switch back to the 5744.

When I used to cast/reload 45/70, I used Unique and got similar results as with your 5744. Pretty good stuff. I used a Lee 405 mold, and it did a pretty good job of knocking steel plates at 100 yds from my Ruger #3. Mild recoil, too. Do you have Lymans cast bullet manual? Lots of info. If 5744 does well in the SD and is accurate, why change. Good luck.

Hello BobbinIL,

I have handloaded for many years with this cartridge and have never seen an instance that warranted Mag primers. Perhaps if you are loading ball powder or loading large loads of slow powder(4350,4831,etc.) Slow powder is relatively inefficient and leads to a high cost per round!
Try IMR4198 at 29-30 grains, 400 gr. lead or jacketed, always shot very accurately with only drawback being does not flow through powder measure well. Also, 24 gr. 2400, 400 gr. lead or jacketed, accurate and flows well.
See ya, Richard

Had to switch to Mag primers in my 45LC when using AA5744, just to get the stuff ignited a little better.

I am working up a load for my Winchester 86 in 45-70 and having quite a time geting something I like. I am locked into a 405 grn RNFP bullet cast with a lyman mold. I load with a good roll crimp and Win large rifle primers. my goal is to find an accurate load in the 1250 FPS range. I am currently using IMR 3031 and finding that is is very inconsistant. I have tried 36 grns of 3031 and was getting around 1200 fps with a wide diference in velocity from shot to shot. close to 50 fps SD. I will shoot 3 shots and get the following velocities 1150 1190 1230 So I bumped up to 37 grns an got 1230 1250 1300. As the barrel warms it seems the velocities het higher.

If I reduce back to 36 grns of 3031 and switch to magnum primers will I get more consistant velocities? I was loading 5744 and a cotton buffer and the velocities were very consistant <8fps deviation from shot to shot. If I can't get the 3031 to perform I will switch back to the 5744.
BobinIL,
I think that 3031 powder is a little slow burning in the 45/70 at those low velocities.I get unburned powder in my Trapdoors.
Try using 4198 or Reloader7. 30 grains of 4198 with standard primer will give you around 1300 FPS,and is consistant.
Frank

I was just about to ask a similar question.
405gr cast bullet
52 to 58gr Hodgdon H322 powder
CCI Primers
in a Marlin 1895 22in barrel

I have not shot this load yet but...

The load calls for CCI Primers. I have bought stock in 1000 Fed 215 Magnum Primers from my past 300win mag loading days (sold rifle).

What are the adverse affects of going to a Magnum Primer. I understand it is not necessary with some powders but it would be nice if I could shoot up these that I have already.

Any thoughts or experiences out there on this?

You won't hurt anything switching from standard to mag primer if you will back off a few grains of the powder load to compensate for the hotter ignition.

Switch to the mag primers and RX7 start low and work up as usual. You will find what you need. Take care and have fun. Swany

Switch to the mag primers and RX7 start low and work up as usual. You will find what you need. Take care and have fun. Swany
The 45/70 cartridge will accept any primer,if you match the powder to it.
I've shot a lot of Red Dot 'fun loads' with large standard pistol primers.
I also recall,a while back,a magazine article about using shotshell primers with surplus military powder. The primer pocket had to be enlarged.
I used magnum primers with IMR 3031 loads.That's the slowest powder that I ever tried in the 45/70.
Frank