43 Mauser - PP Bullet size?

[arclight]

Hi all,

I'd like to test out some Paper Patch loads in my .43 Mauser. I have the Lyman .446 Mold, and that bullet will barely chamber unless I post-size the loaded round.

I'm new to paper patching. Can someone give me a suggested boolit to start with? Maybe a .440 or the smaller .43 Spanish slug?

Arclight

[45 2.1]

Hi all,

I'd like to test out some Paper Patch loads in my .43 Mauser. I have the Lyman .446 Mold, and that bullet will barely chamber unless I post-size the loaded round.

I'm new to paper patching. Can someone give me a suggested boolit to start with? Maybe a .440 or the smaller .43 Spanish slug?

Arclight

Measure that round that will barely chamber on the neck. Whatever that is subtract 2 case neck wall thicknesses and 4 patching paper thicknesses then add 0.001". That is your boolit size pre patched. The Lyman 43 spanish slug casts out at 0.440" for me and patched with two wraps of 9 lb. onionskin (0.002" thickness) paper gives 0.447" patched diameter. My rifle will accept a 0.450" boolit also, yours would seem to have a smaller throat in it. Make sure to engrave the loaded patched boolit into the throat origin into the rifling some. Patched boolits won't tolerate a jump to the rifling if you want accuracy.

[docone31]

I do not if this helps.
I have a .303 British Smelly. The reccomended jacketed bullet is .311. My bore is loose, it prefers .312 jacketed.
When I tried paper patching, it was reccomended I try .308, wrapped with two wraps of Meade Traceing Paper. That gave me .3125.
When I fired the reccomended sizing cast, I got 20ft groups. When I fired the paper patched .3125, I got 5ft groups.
That said, I tried 3 wraps of Meade Traceing paper. I got 3" groups with what would be considered a stout load for lead. Paper does make a difference.
What I needed to do, which I later did, was slug the bore. I had read the bore was .303. I got .304.
The Meade Traceing Paper measures .0015. Two wraps gave me .003. So, .308 plus .003, I got .311.
.3125 gives me 3" groups with no pressure signs at minimum starting load for jacketed.
I am going to try .314 with two wraps of notebook paper.
I do not know the jacketed dimension reccomended for your rifle. However, a .308 with three wraps of .0015 gave me good results on a bore that is .312.
If you can get slug dimensions, then convert my numbers, you might get a starting point.
It is simple to slug. With your rifle, you might try a .38 lead wadcutter driven down the bore.
I had the benefit of someone who had done it previously to help me with a starting point. They were loose for me, but it got me a start.
The main thing is to get a baseline to start with. I have read that paper goes .002 over total bore.
Once you get it dialed in, I think you will find it comfortable to do.
There lots of folks who should be able to fill in the blanks.

[arclight]

I'd be willing to trade boolits with someone to get my hands on a few .430-.440 dia slugs in the 340-400gr range.

I can trade:

.446 Lyman 350GR
Various hard-lube .358 boolits
1.25oz Lyman 12ga slugs
7/8 Lee slugs


Cheers,

Arclight

[uscra112]

The Mauser 71/84 has a deliberately small neck. Not designed for nekkid boolits at all.

Ijust posted the dimensional data for the original paper-patched OEM Mauser rounds in the "CB /Military Rifles" forum. (I have a double handful, and pulled a couple down for study.)

The main trick will be to use a dead soft boolit, sized such that, when patched, you can just chamber it in a clean rifle, assuming that your are shooting smokeless. Shooting "dirty" with BP, the OEM dimensions should make a good starting point.

[missionary5155]

Greetings
That .446 boolit is the same I use in my 43.Spanish rifles.... In mine it shoots well enough it will pop coyotes out at 100 yards. Pure lead flat smacks-em into the turf.
The regular Spanish boolit from lyman falls at .4375 from my mold... Sort of big for PP... BUt if you have a .429 or so sizer die push the pure lead boolit through nose first (works better if you can do it in 2 stages .. start with a .439 if you have one) . Trim off ther "extended rims" and rap them. As ststed above you need to know bore size, paper thickness x2 and case neck... With 2F Black they will bump up in the chamber so you can be a hair small.

[arclight]

Thanks everyone for the input. I think I'm going to spin a custom mold for this and try it out.

I did the math, and I think I can make a round-nose pure lead slug drop at 375gr with the OAL I want. Since this will be PP, there are no grease grooves to worry about cutting, and I'm pretty sure I can make the cherry I need from O-1 drill rod.

Is there any problem with using a RN profile in the Mauser tube magazine? Should I make it a flat point instead?

Arclight

[pdawg_shooter]

Slug your bore, size your bullets .001 to .0015 over bore dia. Wrap with 2 wraps of 16# paper, let dry and clip the tails. Lube and size with a push through die to throat dia. or up to .001 under throat dia. Load like a jacketed bullet and go shooting.

[uscra112]

I've pulled down one of my OEM Mauser cartridges, and found that the bare boolit, which is swaged, soft lead, flat point, (meplat about .265 inches), no grooves, weighing 387 grains, has an outside diameter of .430 inches at the base, and about .428 at the point where the ogive starts. This makes sense to me - the slight draft angle would let them come out of the swage easier. Overall length is 1.040 inches. Base has a flat rim about .070 wide around a more-or-less spherical hollow about .030 deep.

With the patch, the diameter was (is) .438 inches. All 20 of my rounds are the same on this last dimension.

This should provide you with a known starting point. I think that these were as small as they were because they positively HAD to chamber in fouled rifles. In a clean rifle, you should be able to go as large as will chamber, which might well mean that your slug as patched would be .446 inches, inferring a bare slug of maybe .438 to .440 inches. However, you will need to look carefully at the throat - a boolit that large may be bigger than whetever passes for the entry to the forcing cone, and if that is the case, the patch may get torn or scraped off upon firing. I'm busily acquiring a reamer to correct that exact problem in one of my .30-30s.

Round nose is a major non-no in that magazine, just as in any lever-gun. Don't even think about it, with those big powder charges right by your left hand and wrist.

[arclight]

Thanks for all the help on the dimensions. I finished making a cherry and cutting my first mold today. Check it out:

http://23.org/~arclight/photos/100_1614.JPG

http://23.org/~arclight/photos/100_1621.JPG

Link (Sometimes my gallery has issues):

http://23b.org/gallery/v/23b_members/Arclight/projects/metal/metal_working/bulletmolds/


I made a 3-flute cutter out of O-1 drill rod, cut the reliefs with a file and then hardened with the oxy-acetylene torch and a motor oil quench. I ran a couple of test boolits, and they seem to drop at around 340gr and .436 with some mixed WW alloy I had in the pot already. I'll have to get some softer alloy soon. But for now I have a couple of slugs to get my patch on with.

Arclight

[montana_charlie]

I looked at your pictures, Arclight.
You wanted something you didn't have, so you made it...and did a nice job, to boot.

I admire your attitude, and ability.

BTW...what made you pick your username?
CM

[arclight]

Thanks - I made a few mistakes, but it bullets fall out cleanly and the right diameter.

I've had this name since BBS days, when I could only have < 8 characters for a username.

Will get some pics of the machining setup soon.

If this works out, I'm willing to make more or lend out the cherry to someone with the right setup.

Arclight