Rimmed 10mm magnum

[Aggie01]

I'm wondering who can help me with ideas for the shooter grade OM 357 I got via Kings6 the otherday.
I want to have it chambered in 10mm magnum, and also be able to make rimmed cases for the same chambers. Will .41 mag ./ 30-30 brass work for this (like a 401 powermag), or is there a better solution? I think that 10mm magnum brass will be fine for everything I want to do with this thing, but I would like to have a rimmered option I f I can.
I'm looking to shoot 180-200 gn standard .40/10mm/.38-40 style lead out of it. Most commercially available projectiles for the above calibers have relatively short NTC lengths, so I don't think I'll have any OAL problems.
Sound reasonable? (note: please only apply "reason" to the specifics of the project, NOT the project as a whole.)
I'm not going to have it refinished or remarked until I decide if I like shooting it, so this will be an "economical" conversion, as far as conversions go. (Notice I didn't say "cheap")

If anyone has a 6.5" OM 357 barrel available, I might be interested, that way I could send it out for a rebore without having to ship this gun off right away.

[Lee Martin]

I'd do it on 30-30 brass and headspace off the rim. The 10mm Magnum is a potent round, but it's better suited for autoloaders. Another option is to do a 401 Bobcat which is based on 220 Swift.

-Lee
www.singleactions.com

[Aggie01]

Sorry I forgot to mention, I'm specifically looking to be able to reload with standard .40/10mm carbide dies, & cut the chambers with a standard 10mm reamer. This project will get shelved for a while if I have to add expenses for custom dies and and reamers to it at this point. I think that rules out the Bobcat, right?

I have a preliminary dummy round made up based on 30-30 brass.
Since I didnt have a .40 expander, (which I should be able to use one for a 38-40 or a 400 corbon) i turned a .40 FMJ bullet upside down and drove it into a cut-off 30-30 case. On this particular piece of brass, it has a .422 base dia, and a .421 OD where I forced the bullet in.

[onegoodshot]

I am having a contender 401 mag barrel being made now. I tried using my 40/10mm dies to neck down some 41 mag brass and ran into problems. I had the best results using new starline, but I still couldn't full length resize down to the proper size. I could get almost 3/4 of it resized, but it would leave a lip on the brass about 1/4" above the rim.
I ended up running a couple orig 401 powermag brass through the dies to make a few dummy rounds. Once I get the barrel, I'll play with it and see what I can come up with. Should be here soon, I'll keep you posted.

[Lee Martin]

Definitely rules out the Bobcat. That requires both custom dies and reamers.

-Lee
www.singleactions.com

[Aggie01]

May 26, 2009 13:08:53 GMT -5 onegoodshot said:

I am having a contender 401 mag barrel being made now. I tried using my 40/10mm dies to neck down some 41 mag brass and ran into problems. I had the best results using new starline, but I still couldn't full length resize down to the proper size. I could get almost 3/4 of it resized, but it would leave a lip on the brass about 1/4" above the rim.

What I read about that (maybe from Lee's 401 article? maybe Fryxell's?) was that you should use a piece of flat stock instead of a shell holder and drive the case all the way into the die, then knock it out from the top with a piece of dowel.

[nobearsyet]

Man, you got me, but let me know what you come up with, this could be a fun one.

[Aggie01]

Welcome to Cartridge Jeopardy!.

The answer: .40 & .41 magnums.

What is the question?

[Lee Martin]

It's funny....when I designed the 401 Bobcat back in '93 or '94, I never figured 15 years later folks would still be interested in middle-bore wildcats. I guess the work of Eimer, Boser, and Herters lives on.

-Lee
www.singleactions.com

[Lee Martin]

May 27, 2009 14:13:32 GMT -5 Aggie01 said:

Welcome to Cartridge Jeopardy!.

The answer: .40 & .41 magnums.

What is the question?

The answer does just fine on its own. No need for a question.

-Lee
www.singleactions.com

[shorty500]

LEE is 100% right on that!! i ignored the .41mag for years because they weren't common around here and duh, i had multiple .44 & .45's etc, etc. then when had chance to put together a semi-matched set of both 4" & 8-3/8" S&W's i learned the ERROR OF MY WAYS! although my 4incher from '67 aint the most accurate gun it is more than acceptable and it's longer tubed companion from '75 is the most forgiving easy to feed revolver i have owned that was a standard production model from the major manufacturers! it absolutely dont care what you feed it. as slow or fast as you want, light or as heavy a slug, factory or handloads--
it just piles the slugs in small round groups and it doesn't drastically shift the point of impact through any of that out ti say 50yards or so. durn i just remembered i need to hunt that gun this fall when deer season opens!

[nobearsyet]

When I still lived in Ohio, the 41Mag was as common in deerstands as the shotgun, kind of almost makes one wonder if you actually need anything bigger for deer.

[Lee Martin]

The 41 has made a nice comeback. When I first built my 401 Bobcat, the old Rem Mag seemed to be on its way out. Ruger dropped it from the Redhawk line and discontinued the 41 Blackhawk for a while. S&W only offered the 6" 657. Since then, Freedom Arms chambers it in their 83 and 97, Taurus added a couple of models, and Ruger has done limited runs as Acusports and Hunters. Even Marlin produced a few 1894s in 41.

41 is a long way from being dead.

-Lee
www.singleactions.com

[nobearsyet]

A very long way from being dead, if I do in fac tbuild the 41 B&W you ca nbet there will be a second properly throated cylinder in the old rem mag as well.