.45-70 in a 45-120?

[The Trinity Kid]

Howdy Y'all.  Didn't know where to post this, so figured here was a good place to try.

Question is; would it be possible to shoot a 45-70 from a rifle in one of the longer 45s?  Would that be a sort of 357/38 type of situation?  Just curious.  Thought I might put something like that in one of my books, but wanted to check the correctness of it.

--TK

[Ranch 13]

Yes it's possible, but the difference in case length leaves a bunch of freebore, and accuracy will likely not amount to much, and the leading problems will be astronomical.

[The Trinity Kid]

I know you can do it with 45-60 into a 45-70, I just was wondering about it all.   Would a 45-90 have better accuracy with a 45-70 through it, than say, a 45-110?

--TK

[Ranch 13]

No, a 45-90 will have the better accuracy with 45-90 cases. There's 3 tenths of an inch difference in case length. That's 3 tenth of an inch that the bullet will have to bump up to .480 diameter and then squeeze back down to .458.
45-100 is 1/2 inch, longer 45-110 is nearly 3/4 inch longer, and the 45-120 is an inch and a tenth longer.
If a person buys a rifle with the longer chambers, then you'll just have to face the music and buy the longer cases.

[Abilene]

The Kid isn't planning to shoot it, he is asking for fictional writing purposes.  So yeah, Kid, if your hero needs to use a 45-90 rifle (or 100 or 110, etc) and all he has is a 45-70 round to shoot through it, then go for it.  But luck will be involved so don't have the shooting distance be too far if you want to be realistic.

[Ranch 13]

Oh hell if it's fer fiction, just have the hero shave some thin leather off his chaps, and wrap 45 colt catridges , and kill all the bad guys at 1000 yds, then hop on his black horse after an early morning cup of coffee in ol Cheyenne, and trot on up to Ft. Laramie to have lunch with his favorite girl..

[The Trinity Kid]

Not a bad idea....

Actually, I have a guy with a rolling block, in 45-120, and he'll need to go close range, but doesn't want to burn his good ammo, so he's going to borrow army fodder.  Better story than any o' that el crapido on television today...

--TK

[Drydock]

Actualy this is NOT a good idea.  The problem is that these .45 rifle cases are not STRAIGHT cases, like the pistol rounds mentioned, but have a fairly pronounced taper.  Thus not only do you have freebore, but a progressive widening of the chamber rearward.  While the round would go down the barrel, you would have a great deal of blowby, and possibly split cases in the longer chambers.  This would lead to rapid fouling of the action, interfering with rapid fire.  No knowledegable rifleman would do it.  The base diameter is the same, but the shorter the cartridge, the steeper the taper.

Here's another thing: the Rolling Block was never chambered for that round.  Unless you reshape the breech block you can't chamber anything that long.  Thus the Rolling Block in the higher capacity chamberings used bottleneck cartridges.

I realize this is fantasy, but its something to consider.  Just my humble opinion, nothing more.

[Pitspitr]

If I understand correctly the Rolling blocks had a problem chambering the long cases. (45-120 and 50-140) I know this is the case with the 50-140. I have a friend who built a 50-140 roller and had to modify the hammer or the breech block (I forget which) to allow the long case to clear it during loading and unloading.

OOPS I should have read Drydock's post

[Ol Gabe]

Speaking of fiction...
In the Heston movie '55 days at Peking', the priest and some of the other defending troopers locate an old broken down howitzer, reattach it to a carriage and proudly announce it as a cannon of dubious character that will shoot "...ammo of approximate caliber..." or words to that effect. It is used in the movie to slow down the Boxers as they try to overrun a defended wall. After several successful blasts the barrel explodes killing the gun crew.
If fiction follows the normal course then this is where some pundit might wryly say "...you'll shoot your eye out!" as the potential for a disaster is always there, especially in something like what you are proposing.
For the sake of discussion in your plot line, you might have the feller scavenge for proper loads from local gun shops, similar to the blind kid running a gun shop and searching in a box for the proper cartridge and tossing it to Russell Crowe's character in the street fight sequence in the movie "The quick and the dead'. Yup, that'll work.
Best regards and good writing!
'Ol Gabe

[The Trinity Kid]

hmm...plot modification.  gears turning...(grinding sounds, smoke billowing from ears,  eraser chewing, mind at a gallop.)

Eureka!

45-90, instead of 45-120.  maybe he'll stick to long-range with rounds loaded while shooting.  He'll fire a shot, pour some powder, thumb a bullet in the case, load 'er up and take down another city dude at seven hundred paces.  After he takes down the gang, he'll go back to the town, pick up the girl(maybe the bankers daughter? ) and ride into the sunset.   Work in progress.

--TK