Reloading for the .43 Mauser?

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Hello,

I have recently acquired a .43 Mauser rifle and some brass/cast bullets & proper dies. I am planning on reloading for it, but can't find any smokeless load data for that cartridge anywhere. I want to reload it in smokeless-only (Alliant's Unique) and I'm not interested in BP, even though it was originally designed for it. And yes, I know that there are quite a few who don't approve of it, but this is the way I intend to do it. My objective is mild loads anyway, nothing hot.

Now, according to the info I gathered so far, there are certain pointers out there. Could anyone please confirm these?

  • Unique load range: 11 gr (mild) to 15 gr (hot);
  • When using smokeless, one has to use half sheets of toilet paper to make a wad/buffer inside the cartridge to compensate for the free space;
  • The use of large pistol primers is to be favored over large rifle primers, because the M1871 firing pin may have difficulty denting modern rifle primers;
  • Some smaller diameter bullets may have to be wrapped/patched with paper (?) if they're too small. Apparently, that's how the original German BP cartridge was designed... :confused:

If anyone has any confirmations or additional pointers on reloading for that caliber, please let me know. I've had some great pointers in the past from many of you, so I'm certain there are at least a few people who have experience with this one. Thanks in advance!

:)
 
Slug barrel to determine proper bore dia. so you can use proper fitting bullets, most folks looking for accuracy in the .43 for CBA matches prefer AA5744 powder.
 
I've been shooting these guns quite a bit for the past five years and find almost none of that necessary.

Use Springfield Trapdoor 45/70 loads. No filler is required for Unique, and I haven't found it necessary for H4198 which I prefer. I use Large Rifle primers and have never had an issue. Cast bullets (of course), correctly sized are usually the biggest challenge. I use 45 Cal bullets sized down to 0.448" (my bore is 0.446" and the chamber neck is of a generous size), but there is a 0.446" sold by both Lyman and RCBS.
 
Thanks for the info. The bullets I have are supposed to be the right diameter, but I will measure it to make sure.

This may seem a bit like a stupid question, but what exactly is needed to down size a bullet? So far, I've never actually ran into a necessity of doing that.

Here's one load I've found so far... seems to be right on the money.


45-70

Bullet: 300gr LRN
Powder Weight: 12.0 gr
Powder: Unique
Velocity: 1,100 fps
OAL: ?
Primer: Win LP

Description: An accurate load in the Marlin 1894CB. Very light recoil, fun to shoot. Definitely not meant for hunting. Plinking or Cowboy shooting only.
 
Unique is a lot faster than something like IMR 4198. For that reason, I would never use any filler at all with Unique (i.e., no toilet paper). I'm not saying it is dangerous, though it might be if you get too much filler in there, I'm just cautious about using filler with fast powders.

Back when I was a teenager, I had a 43 Mauser and at that time, could buy ammo at the store (I think it was Imperial that made it). Anyway, the store bought ammo was smokeless powder, but I have no idea of the load. For this type of cartridge, I prefer medium speed powders such as 5744 or IMR 4198 (or Andy's H4198). You might even consider trying IMR 3031. If your load is too light, the pressure will be inadequate to seal the brass against the chamber walls and your brass will be all sooty on the outside. This results in higher than normal thrust against the bolt face. I like to increase the load until the soot disappears.
 
Win 38-55 said:
Unique is a lot faster than something like IMR 4198. For that reason, I would never use any filler at all with Unique (i.e., no toilet paper). I'm not saying it is dangerous, though it might be if you get too much filler in there, I'm just cautious about using filler with fast powders.

Back when I was a teenager, I had a 43 Mauser and at that time, could buy ammo at the store (I think it was Imperial that made it). Anyway, the store bought ammo was smokeless powder, but I have no idea of the load. For this type of cartridge, I prefer medium speed powders such as 5744 or IMR 4198 (or Andy's H4198). You might even consider trying IMR 3031. If your load is too light, the pressure will be inadequate to seal the brass against the chamber walls and your brass will be all sooty on the outside. This results in higher than normal thrust against the bolt face. I like to increase the load until the soot disappears.
Click to expand...

Thanks! I'll keep that in mind. I'll start with let's say 13 gr of Unique and see what happens. I would try the IMR powders, but for the time being I don't have a source where I could get them.

Thanks for the info... I'm learning more and more every day. This forum is great!

:D
 
I'd have sent you the reloading data that another kind member sent me, but my hard drive crashed and burned this summer.

Kind CGN'er - if you're out there, please repost your data! It was good stuff!
 
H Wally said:
I'd have sent you the reloading data that another kind member sent me, but my hard drive crashed and burned this summer.

Kind CGN'er - if you're out there, please repost your data! It was good stuff!
Click to expand...

That would be very nice indeed.. too bad about your hard-drive. Next one you buy, make sure it's the "Seagate" brand. Best drives in the world and well priced too. You'll never have a problem with these. Samsungs and Maxtors are another story (uber cheap quality!)

tactical870 said:
Anyone know of a factory jacketed bullet that can be used in a 43 mauser application?
Click to expand...

Jacketed? Why would you use that? It will just mess up that old vintage bore... personally, I'd stick to lubed cast bullets only (as recommended for antique guns in my Lyman reloading manual).
 
Some great advice here.

If you want to start with Unique, it's a great powder that doesn't require filler and produces a lot of loads in a pound of powder. However - it will not produce anywhere near top velocities, and will rarely produce the most accurate loads (good, but not the best).

If you decide to go with something slower, here's a few powders that work well and require no fillers:

Varget, IMR 4064, IMR 4895, H4895, IMR 3031, Benchmark, and IMR 4198.

Hodgdon provides load data for all of them for bullet weights from 300gr to 485gr at safe pressures. Remember to look for Springfield Trapdoor 45/70 loads. In fact the Mauser 71 and 71/84 are a bit stronger than the Springfield Trapdoor and the 43 Mauser case is slightly larger than the 45/70, so you could even go a few % higher with your loads, but why would you?
 
Andy said:
In fact the Mauser 71 and 71/84 are a bit stronger than the Springfield Trapdoor and the 43 Mauser case is slightly larger than the 45/70, so you could even go a few % higher with your loads, but why would you?
Click to expand...

Thanks again for the info. I will indeed stick to low pressure loads, as I don't need anything too powerful anyway. I'll see if I can get my hands on some IMR at some point and give that a try as well.

;)
 
Try SR 4759 if you can find some, it is my favourite powder for target loads in .45-70, Win 1886 and trapdoor Springfield.

I use 20.0 grs SR 4759, 405gr cast with large pistol primers for about 1000 fps.
 
Anyone here shooting BP? I was told to load my 43 mauser with 55gr of BP. The downside is I don't have a scale at home. Can I load 55 gr BP by volume with a sliding powder measure? How much free room is allowable in the case? There's room for another 15-20 grains (I have tons of cornmeal for filler if needed). I'd like to shoot this thing tomorrow if possible......
 
IIRC my favorite load was

<insert legal disclaimer here>

CCI 200 LR primer
31.5 gr H4198
~ 1 gr of filler
RCBS .446 bullet
homemade brass formed from 348 Win

1250 fps from carbine barrel

s>
 
Loading with black in the .43 is the same as others, fill with black so that it is slightly compressed(don't use the bullet to compress), there should be NO airspace in your loaded round, you will have to determine how many grains that is. I don't buy the "55 grs. regardless" theory, in some makes of brass, it could be dangerous to your chamber.
 
I am using 77gr of goex ffg used a cardboard wad0n top of powder then a felt wad soaked in beeswax on top for lube and cleaner. can't remember bullet wieght but bought at a gunshow last year. seems accurate enough, cause I am going to try to fill my whitetail tag tomorrow. This is a stout load so copy at your own risk!!! I can't find the website that I got this from.
 
sunray said:
There's one unverified Unique load using a 370 grain bullet on Reloader's nest.
Click to expand...

Thanks, I'll give it a peep for sure. :D

By the way, does anyone know what the case/OAL length of the 43 Mauser should be?

My dies came without the small Lee pamphlet, so I don't have much of a reference (and a google search wasn't much help either)... I saw 2.376" as trim-to case length somewhere... can anyone confirm this?

Thanks!
 
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