I'm considering building a .45-120 but don't know squat about black powder loads. I have several questions....
1. if I use black powder what kind and how much and any other advice you can offer
2. If I use a smokeless powder what kind and how much and any other useful info you can offer.
3. Cal I shoot .45-90 or .45-70 ammo in a .45-120 chambered gun?
If I build this it will be on a side X side 20 ga shotgun of modern steels but would confine myself to 35-40K PSI. It's use would be for pig hunting in southern states and not at all an African gun!
What's say you about paper patch bullets?....or should a hard cast bullet work best?

Great cartridge, i have two '74 Sharps 45 3-1/4, i take it you have dies and brass?

I would never load smokeless in a case that long, you're asking for a rung chamber.

100gr 2F blackpowder will do all that needs done, i shoot the 1881 Saeco 500gr grease groove bullet, compress your powder with a 458 cal compression die with 30 thou Walters fiber wad on top, compress enough to allow for a 3/16 ths or 180-200 thou thick grease cookie and bullet seated so just a bit of the top driving band is visible, close the case mouths with a taper crimp die or remove the decapping stem from the size die and use it, close just enough that you get a bounce when dropping a loaded round in the chamber with the butt of the rifle straight up, no need for over or roll crimping single shot rounds.

That's the load i shoot n my rifles, the velocity is 1488 fps, i have taken that bullet to1650 fps with 120gr Old Eynsford 2F, that's not necessary, i have a Saeco mould and cast my hunting loads with 16, 12, and as hard as 10 to 1 alloy, it all works, as would store bought bullets made with 20 or 30 to 1 alloys.

BTW, i have a 520gr paper patch hunting bullet mould, it's around 1.325 long, wears a .250 thou flat meplat, but, with only 250 thou of that bullet seated in the case, carrying around 45 3-1/4 paper patch loads makes one feel like a serious case of over-compensation, they work fine and shoot great, just look goofy.

gunner500, thanks for the info.....I do appreciate it. I'm not at all surprised that you warned against smokeless powder. Further, as I said, I am not at all familiar with black powder but I do know about 2f and can easily weigh 100 grains. I'll have to do some research on the bullets as I was expecting the use of the same cast bullets used in the 45-70. I have no clue what a walters fiber wad is nor what a grease cookie is.....but learning is part of the entire exercise.. Again, thanks for the feedback.

Gunner is a solid educator on these. I know I am continuing to learn as I listen. Those big BP cartridges are some kinda cool.

vapodog, you're most welcome.

Borrow or steal a square glass baking dish from your wife, buy some SPG lube from midwayusa or Buffalo arms, melt in oven on lowest setting, around 180 degrees till lube sticks are melted enough that they cover a spent rifle primer laying in the bottom of the pan, that's an easy to measure and will give plenty thick enough cookie.

After lube it cooled and after you have compressed powder with wad stab the case mouth in the lube, turn and pull back, thumb the cookie down then stab the top with a small screwdriver, i use a brass rod about the size of pencil lead, lets the air out from under the cookie, have the cases previously belled enough at the mouth that you can just start a grease groove bullet by hand, use die to seat cookie and bullet on down to the top of the wad, no need for a second wad over the cookie, a grease groove bullet will easily sit on top of a lube cookie.

You can buy at Buffalo Arms/Midwayusa:

Walters fiber wads in 458, 30 thou thick
Lyman or other make 458 cal powder compression die
Lyman or other make 458 cal taper crimp die

And yes, any cast lead or even hard cast gas check bullet for a 45-70 can be shot in the 45 3-1/4 inch, an 18 twist barrel will stabilize up to a 570gr bullet, if going 20 twist i'd keep bullet weight less than 520 grains or 1.330 long.

I like a flat nosed bullet with at least a 200 thou meplat for hunting light big game, deer/pigs, for elk, moose or buffalo a round nose is just fine, those large animals make ANY bullet nose shape work due to their sheer mass.

Thanks Big Buddy Beretz, it's a hell of a fun sport.

Correct me if I am wrong but I believe with black powder you don't weigh 100 grains of powder but rather fill by volume a 100 grain cylinder and then use that volume amount.

I would skip 45-120 and rather get a real Sharps round, the 45-110, 2-7/8. The 3-1/4" casing was never made in a production Sharps rifle, but the 2-7/8 was.

I use 103grs of 1F (have tried OE yet) with a 540 Steve Brook grease groove bullet.

Another place to get a lot of info for shooting BPCR is on the Shiloh Rifle site. Shiloh Sharps forum

What Gunner said. Hope the barrels regulate well

You weigh the charges and then slowly dump the powder down a drop tube to fill the casing or a vibrator to settle the powder in the casing

I have all three, 45/70..45/90..and 45/110... Wouldn't even consider the 120 for multiple reasons...All three of these shorter 45's are more than capable when stoked with BP using proper bullets & loading techniques , therefore any advantage you think it might have over the "90 or'110 comes with the cost of managing a very long powder column consuming mass quantities of BP to achieve similar performance with any minimal gains { I doubt there are any IMO } over the shorter 45's..

You're making way too much sense and I'm giving this serious thought!

You`re right. I have a 110..lots of BP. and I`ve shot smokless in it too, with a filler...you can also shot a duplex load with smokless to control BP fouling. Works,
Doing it again, I would go 45-70...many more options, including brass, factory loading etc, etc.

If you`re looking to impress, the 110 case with PP bullets sticking out will be a conversation starter.

YMMV

You bet Dan, in a modern built double rifle that the OP is contemplating building, what Sharps did or didn't do means nothing, the 45 3-1/4", short a bit of rim difference, is a twin to the great 450 3-1/4" Black Powder Express, a cartridge with a rich, rich heritage in the early African game fields, i can't think of a cooler build myself, plus, we all know what the 450 3-1/4" BPE turned in to with the invention of Cordite, the 450 Nitro Express, both 3" and 3-1/4"..........cool stuff Sir.

It is most impressive especially topped with PP...

It does mean something to a lot of people, including myself. I originally ordered my Shiloh with the 3-1/4 but changed it because I would also rather have something that also has originality with it. I wanted to make sure the OP is aware that the 3-1/4 wasn't a Sharps cartridge.

And if you really want a cooler cartridge try the 44-77bn or better yet, the 44-90bn

I know what you're saying, i have 44-77 SBN, 40-90 SBN, two 45 2-7/8, one of those is an original Sharps, two 50 2-1/2" a new double rifle build has nothing to do with original Sharps Rifle factory chamberings, it's all good though, Blast away and kill things to eat!

I built myself a 45x2 7/8 about 40 years ago. I built it on a Ruger No. 1. I used smokeless powder primarily, but also used black with a smokeless priming charge (700X). Of course, the Ruger is a strong action and the 45x2 7/8 could be loaded as heavy as you wanted to which. A 400 grain Speer bullet, at 2650 fps, did amazing things to a watermelon!
By the way, I once passed on a beautiful Lang & Sons double, BP proofed, in 45x3 1/4. Damascus barrels and both were unblemished inside and out. I should have bought it. GD

Yea, looked great in Quigleys` belt, no?
A friend asked what I was going to hunt with it...told him "anything I want". Killed a number of deer and one "Speed Goat" with mine..never had a chance on Elk.

more questions:
Is the 450 Nitro express the same as the .45-120?

Is the .45 Basic the same as the .45-120?

Both are said to be 3 1/4 ' long....

As said earlier there may be a slight rim difference, the 450 Nitro Express comes in 3 and 3.25" versions, i took it you had 45 3-1/4" brass, hence the title of the thread, i have some i'd sell.

BTW, the basic made by Norma is for the 45 3-1/4"

If you have some Norma 45-120 brass you want to sell please PM me a price. Maybe we can do some business.

I have Jamison, Bell and HDS [Huntington's Die Service]

My problem with black powder cartridge loading is that its different from smokeless. The guys who are into it act like they expect everyone to know loadjng techniques and that they know the terms and knowhow right from the get go. Its somewhat confusing for newbies.

Thats why even though im interested in it i didnt get started.

I find your statement completely wrong. The BPCR people seem to be more helpful in reloading than any other shooting group. Go for a gander to the Shiloh website and look at how many folks over there help the newbies shiloh forum

Also look for several BPCR books: MLV's BPCR Primer book and Paul Matthew's series of books are very helpful

Over my shooting life I have had about all the rifles and calibres I ever wanted and some rifle/calibre combinations i have repeated many times over ;0 The one regret is I never got one of those Shiloh rifles. Lots of things like when spare money was these I did not want the wait etc. i would have got the 45-120 but I am first to admit if I had gone ahead with a purchase and found out more then maybe it would not have been a 45-120

RifleCrank on the big 458 thread in Express Rifles forum has posted a lot about the fellow who did the real long range shooting with them and on game and plenty of pictures. Truly amazing.

as far as i am aware, the 450X3 1/4 nitro express as designed by rigby was always 3 1/4 inches long.

rim thickness is about .040 inches. in contrast to the 45-120-3 1/4 Sharps cartridge, which is shown in the lyman 50th edition as having a rim thickness of .070.