Any 43 Mauser fans here loading IMR 7383

[johnly]

Spent some time casting some 390 gr. bullets from a RCBS 43-370 mold and now it's time to load some ammo for my M71/84 and take it to the range.
I could use H4198, 3031, or RL-7, but I have a huge stash of 7383 that is looking for a purpose in life. I've had really good success with it in my 358 Winchester and my 416 Taylor shooting cast bullets, so I would like to give it a try in the 43 Mauser. My concern is that the M71/84 is a 25,000 psi action, so there isn't a large margin for error as compared to modern actions. I could test similar loads in my 45/70 Encore rifle to see if any abnormalities are observed. Either way the loads will be shot over a chronograph to see if higher than expected velocities are observed. Frankly I'm expecting modest velocities and lots of un-burned powder, just like BP loads, but if it's accurate I'll be happy. Using 4350 as the burn rate, I'm only seeing 13kpsi with a full case.

Anyone traveled this route before me?

[GregLaROCHE]

If you have problems with unburned powder, you can try a tighter crimp and magnum primers. I had a powder that was specified for 45/70 rounds, but all the powder wasn’t burning. A tighter crimp and magnum primers helped some, but not completely. I finally got a faster powder to use.

[wyowillys46]

https://castboolits.gunloads.com/sho...-it-compare-to

I probably wouldn't experiment with a temperamental powder like 7383 in a 71/84. A more modern action, maybe.

[pworley1]

There will most likely be a good bit of unburned powder unless you get the pressure above 35000 psi. It will shoot, but I think you have better choices for the 43.

[sharps4590]

Yes sir, I'm a fan, a big fan of the 11.15 X 60R. No sir, I have no experience with 7383 and am not likely to. My absolute best results have been with 5 grs. of SR-4759, (I expect any other powder known for success in duplex loads would work as well), under 68 to 70 grains of Schuetzen, Old Eyensford or the first generation of GOEX Cartridge...which hasn't been available for about 30 years. but, I have a couple pounds left. I like that RCBS bullet but it wouldn't regulate in my Goldmann double rifle. The Lyman bullet for the various 43's at about 350 grains is the one that shot best for me and it is cast 25-1.

That was my experience after about a year of experimenting with a bunch of powders under various bullets. The Hawk jacketed bullet gave good results but not enough better than cast to justify the expense.

I think it's an excellent old cartridge and a lot of fun in an 1870's double rifle.....good killer too!!!

[Gobeyond]

No, don’t use that stuff- too high tech. Some of the others you mentioned seem a better choice. BP is fun and a natural for the 11mm Mauser. Smokeless is allowed but don’t be too much a maverick in your choice. 390 sounds like a good bullet, good penetration and all and the right weight. I use 73 gr of bp and shooting a 480 gr postell, pretty decently.

Where would you even start with that powder? It might be position sensitive. Isn’t it for magnums?

[Dhall_37]

I load the 42 Russian, very similar to the 11mm Mauser. I’d stick with 3031 or 4198 they’d give the best burn rates and velocity. However I load BP for the Berdan II.

[dogmower]

I shoot the lyman 446110 powder coated, over 29 grains IMR 4198 in my 71/84. Connects easily with a 9x13 steel plate at 200 m