Pump action for 45-70

00scoots

I've always preferred a pump action rifle over a lever action, but as far as I know a 45-70 has never been made in a pump action....and I would certainly like to correct this if possible.

Would it be possible (and I'm just thinking out loud here) to fit a rifled barrel chambered for 45-70 onto the pump action of a shotgun?

Certainly the tubular magazine and shell carrier of a 12 guage would be far too large for a 45-70, but would a .410, 28 or 20 guage work?

Is the pump action of a shotgun of sufficient strength to withstand the chamber pressures of a 45-70 cartridge?

I was just wondering the possibilities..........

You can never have too many guns!!!

RockinU

Uhh, that sounds a little dangerous to me...I'm thinking that most shotguns aren't designed for those kinds of pressures...I think instead of tinkering around with something like that, you might just try to find a rifle that fits your needs that is already produced in a pump. I have a .270, and I know there are plenty of other options our there.

v35

Hmm, a Winchester Model 42 in 45-70. The idea sounds neat. The breeching lockup of the gun would have to be analyzed and tested because even the light 45-70 loads operate at 50% greater chamber pressure than the 410. If you go up in shotgun size to 12gauge, the breech will work with the higher pressure 25000 psi .45-70 loads.
A conversion of a Remington high power pump rifle would be a better bet if it could be done because then +P loads could be used.

00scoots

The reason I bring the subject up is because I have come across VERY inexpensive Norinco and IZH SXS 12 guage boxlock shotguns that come with inserts to chamber AND FIRE 45-70 cartridges!!! I believe Stoeger offered a similar inexpensive shotgun with inserts in the late '60's, but senility and time can play tricks on memory!!

I figure if a VERY inexpensive boxlock with inserts can fire the 45-70 cartridge, then a well crafted Remington, Winchester, Browning, or Ithaca pump action shotgun may very well do the same!

You can never have too many guns!!!

JudgeColt

A single or double barrel shotgun has a standing breech that will hold huge amounts of pressure. (Look at the amount of metal behind the case head.) However, a repeater shotgun has a moving breech block and cannot stand very much pressure. Just look at the usual shotgun lockup. It is often just a door-latch style arrangement. These actions are not designed for even low rifle pressures.

If you must have a slide action .45-70, get a large-frame Colt Lightening in .45-60, 45-65 or 45-85. Anyone will chamber and fire the shorter .45-70 at standard pressures, the same as a .357 will chamber a .38, etc.. The Lightening action is not strong enough to hold a hot-rodded .45-70 like we now see edging toward .458 power, so stay with factory loads to avoid destroying a valuable gun and yourself. Although expensive, a large-frame Lightening in shooter condition would probably not cost much more than what you would spend trying to adapt a shotgun to fire a rifle cartridge. (Where would you get a rifled barrel for a Model 42, for instance?)

As far as converting a Remington M760-type pump rifle, I doubt that could be done. I converted a M742 to .300 Winchester Magnum and the bolt face was just large enough, after modification, to accept the larger cartridge head. A .45-70 cartridge head is about the size of the outside diameter of the bolt on a M760. How would you fit an extractor when the entire bolt face is removed? How would you get the rimmed cartridge to feed? What would you use for a magazine?

I love to do things out of the ordinary, but I think this is beyond anything practical or safe.



Edited by - JudgeColt on 04/27/2002 00:51:00

v35

You can turn 45-70 case heads down to '06 dimensions and use the unaltered Remington bolt face. The 45-70 body diameter is close to the '06 base diameter so you may have less of an alteration than you think. It's no big deal to lathe turn the 45-70 straight case heads and reform them to '06 size.
It sounds like an exciting project.

JudgeColt

In response to v35's reply, if a custom case is acceptable, I would just start with the .30-06 case and blow it out to accept a .458 caliber bullet. (The cartridge would look a lot like a "derimmed" .45-70.) Then all you have to do, is rebore or rebarrel any standard Remington .30-06 casehead-based pump and you are there. However, I understood that the desire was to use an unaltered .45-70 case, which I do not think can be done in any reasonable fashion.

Again, just buy a large-frame .45 caliber Colt Lightening and be done with it!

gap1916

OK What about a bolt action 45-70? Gibbs Rifle company makes one. Check it out.

00scoots

Well, after finding a couple of Colt Lightnings for sale and none in 45-70, but all at museum prices, I have decided to further investigate case alterations.

Milling down 45-70 case heads to the dimensions of an '06 case head appears to be a project that can be done by the amateur home gunsmith.

What is needed to "blow out" an '06 case to accept a .458 caliber bullet? Could this be done at home without upsetting the neighbors?

Which way would you go?

You can never have too many guns!!!

v35

A decent machinist could make you a rim reforming tool to put in a lathe toolpost that would make all cuts in one shot. Why not make up a couple of dummy rounds each way and see what you're up against in the Remington pump receiver and magazine. The 45-70 case will have to be rebated since it is .030" larger in diameter than the '06 base.

pit-sitter

Shooting from the hip, thatis without looking up the measurements.
I think that a Savage m170 pump action rifle might be a solution.
They start out as 30-30 and a rebarrel might take care of everything.
On the other hand somebody will probably be along soon to explain what is wrong with this idea.
Chris