Need your help?

[edgemark]

I am new to the forum, and have asked this elsewhere. Someone said that this is THE place to ask the question.

A little background. I make muzzleloaders that shoot smokeless powder. Most use Savage actions and premium barrels. I want to test some experimental breechplugs and don't want to scrap an expensive barrel so I am looking for a cheap substitute.

I can pick up a NEF Handi-Rifle in 45-70 or 50 S&W for about 200 dollars complete....can't get much cheaper than that 

I really want a cheap 45 to play with since this is only to experiment with, and accuracy is secondary.

The Handi Rifle comes in 500 S&W ( 50,000 psi )and 45-70 too, but the 45-70 is generally a low pressure cartridge since its origins are in BP.

My loads will be in the 50,000 psi range.

Two considerations need to be taken into account as to load pressures:

1) The Barrel. If the 500 S&W Magnum is a 50,000 psi cartridge, AND the 45-70 and the 500 S&W utilise the same barrel contour then I think that the barrel is up to the task in the 45 version too;

2) The Action. Bolt and Falling Block actions are known for their strength. Break open actions and lever guns are not. Clearly the action needs to be able to take the full pressure should you experience a case head separation. The 500 S&W Case is 0.526 in diameter under the head which would translate to a case separation pressure of 10,865 and the 45-70 Government is only .505, which translates to just 10,000 assuming a 50,000 psi load.

My question is does anyone have any knowledge about the Handi rifle that would make you not use full power loads in a 45 barrel ( 50,000 psi)?

I realise that this may seem to be off the wall, but I really just need to know if the 500 S&W barrel and the 45-70 barrel have the same outside contour, AND is there any reason to think that the 45-70 barrel is NOT up to the task of 50,000 psi loadings.

Thanks for your assistance with this project.

edge.

[quickdtoo]

All H&R/NEF barrels cept the 10ga and 12ga slug gun are the same diameter at the chamber swell, ~1.1", the .45-70 and .500S&W have close to the same barrel contour, but the .500 is about .090" larger at the muzzle. FWIW, Smokeless Muzzleloading makes smokeless barrels for H&Rs.

Tim

http://smokelessmuzzleloading.com/

[edgemark]

Thanks Tim.

I am well familiar with SMI and their quality work.

I am just looking for an inexpensive way to experiment with a new breechplug design. A 1.1 inch diameter should be a plenty strong barrel for smokeless loads. I appreciate your help.

edge.

[billy_56081]

The only thing I can think of that might keep me from using 50k loads in my handi is recoil.

[Mac11700]

All H&R/NEF barrels cept the 10ga and 12ga slug gun are the same diameter at the chamber swell, ~1.1", the .45-70 and .500S&W have close to the same barrel contour, but the .500 is about .090" larger at the muzzle. FWIW, Smokeless Muzzleloading makes smokeless barrels for H&Rs.

Tim

http://smokelessmuzzleloading.com/

I've always check my loads for signs of pressure...mic'ng the cases...checking the primers & pockets...going over the brass with a fine tooth comb ...but...the guys in the link Quick provided say this on their data page...

THE ABOVE LOADS ARE MAXIMUM LOADS , ALL LOADS SHOULD BE REDUCED BY 10 PERCENT AND WORKED UP TO MAX LOADS WATCHING FOR SIGNS OF PRESSURE.

What pressures signs are the looking for? The gun coming apart all of a sudden?...( a little tongue and cheek humor here )

Mac

[edgemark]

Edge, show a pic of the work you have already done and what you plan to do. The one you showed on LRH is a work of art.

For now I just want to test a breechplug idea that would not destroy the barrel. If it works you could switch back and forth between cartridge and ML with little effort. No pictures yet, just thoughts rolling around in my head 

edge.

[edgemark]

In looking through the Hodgdon cartridge reloading data for the 45-70 Government ( Modern Rifles ), they list a max load of a300 GR. bullet, H4198     63.0grains, yielding 2532fps  @ 50,000 CUP

If worked up slowly in a Handi, would this be a safe load ?

I would prefer a 250 grain bullet, but this load would work for my testing......my shoulder may not look forward to it, but my breechplug needs the testing.

edge.

http://data.hodgdon.com/cartridge_load.asp

[quickdtoo]

Shooting a lot will most likely cause the underlug to set back some resulting in a loose barrel eventually. I don't think you're going to see any catastrophic failure from what we've learned of their frame strength and proofing, but I wouldn't advise shooting that load a lot, there have been a few .500 S&Ws reported shooting loose from max loads, and the same thing happened to a .308 Win barrel rechambered to .300WSM, although that was with full factory loads. H&R will tell you that levergun loads are the limit, so I wouldn't tread in that territory a lot. NFG has chrono'd 300gr bullets over 2600fps in a 32" BC barrel, but I've only pushed 300gr Nosler PPs to 2425fps in my 22" Handi, that's a good stiff levergun load that's safe in an 1895.

Tim