I haven’t tried it, but here’s my two cents worth: try it and see. You don’t have anything to lose at this point. Worse case scenario, rebarrel it if you can’t get it to shoot. My money’s on it probably will shoot “OK” with 45-90.

 

Unless one intends to shoot black powder for a particular reason the 45-120 & 45-90 are not in much demand as the 45-70 with modern smokeless powders will duplicate the longer case performance levels. I would either sell it to someone that specifically wants the 45-120 or set the barrel back & set it up for the 45-70 & eliminate all the headaches! Just my two cents!

 

I already have a Sharps in 45-90, and an original Springfield Trapdoor & Marlin in 45-70. Aside from this Sharps being cheap (now I know why) it was the idea of something different. Rather than rebarrel or rechamber it, it will probably go down the road, and I'll get something else.

 

OK, range time with the shorter brass shows promise. Used Triple 7 powder, as that was handy. Next time I'll use real black.
Only shot at 25 yards, as I had no idea where this thing was pointing. Groups with 45-70 brass were nothing to brag about, 45-90 brass was better, with about a 3" group. Still not great, but proved getting the bullet closer to the rifling was better. Still looking for the right brass.

New problem. The nice (Pedersoli) Creedmore rear sight wouldn't adjust properly. Had to take it off to use the barrel mounted ladder sight. In the process, I stupidly lost the spring stock that locks the sight upright. Now it is loose and unusable. Email to Pedersoli did not get a reply, and internet seaches turned up nothing, not even a picture of what I lost.

If anyone out there has a Pedersoli Long Range Creedmore sight, and is willing to get a picture of how the sight locks, be it flat sprng stock, or ball, or something else, I'd appreciate a picture. Pretty sure I can make what I need, just need to see one.

Thanks in advance.

(Sight adjustment problem fixed once i cleaned "gunk" out of the threads.)

 

Those aren’t the best sights to begin with. What makes a good/great sight is one that is completely perpendicular to the bore from bottom to top, and the detects are very precise. Even a very minute amount of cant on this type of sight will ruin groups. Call Lee Shaver and look into one of his very good, and quite affordable sights. He may even have a part for your Pedersoli as he was at one time their N. American warranty guy.
If you’re using cast bullets you’re going to have to slug your barrel to even hope of getting any kind of accuracy out of that gun. I’ve owned several Pedersoli Sharps guns and they can be made to shoot great groups. You might want to try some 400/405g jacketed bullets out of that gun. I shoot Rem 405g JSP bullets out of all my Pedersoli guns and my Winchesters (Miroku mfg) they work with several different powders. I believe you can get that gun to shoot if you try some of those bullets and some Rel7, 4198, and or some 2400 powder. I could get consistent 1moa with all those powders. If you can’t get any of those bullets, I just bought another 500pcs off a gentleman on another site. I’ll send you some to try if you’d like if you simply pay what I paid plus the shipping. Up to you if you want to try some, I’m not trying to sell you anything. Just trying to help you out.
I let a younger friend of mine shoot one of my 45-70s with some “odds and ends” ammo I had with me. He hadn’t shot a 45-70 before and hadn’t shot this gun. Here’s what he got at 100 yards off a portable bench we were using. Not too shabby.

 

nsb: Lee Shaver was a good suggestion. He fixed me up with new spring and it dropped right in.

As for brass, I found someone with 450 Nitro Express brass and bought it. Several people on various forums believed it would work. I should have done the research myself. The NE brass is the right length, but the diameter is way too big. Doubt I can jam it into 45-120 dies without buckling. As for that, I can't even try. The rim is too big diameter to fit the 45-70-90-120 shell holder. I ordered one that should work from RCBS, but I probably threw my money away (again). I'll try to resize the NE brass when it arrives, bu at this point I am in the market for actual 45-120 brass again. In the mean time I'll try real black powder in 45-90 brass and see if it shoots better. Paper patching some freshly cast bullets to compare with ones with grease grooves too.

 

Did you slug your barrel yet? Are you shooting cast or jacketed? These are two very important questions to answer if you’re trying to get accuracy out of your new gun.

 

I only use cast in my 2 Sharps & Trapdoor (jacketed in Marlin). My Lyman sizing die is .458". The barrel slugs (using pure lead) .452"-.458" lands & grooves. The actual cast bullets, after sizing & lube with SPG bullet lube is .458". As I haven't had the opportunity to do any paper patching yet, I can't say what the patched bullets measure, but before batching the as-cast bullets are .453" and weight 475 gr on average. I have other molds for various bullet weights that I can eventually try, but even with properly sized bullets, the jump from brass to rifling may mess up decent accuracy. If all I get is "minute of cow" at 100 yards, I won't be happy.
I do have some 325 gr cast bullets for 45 Colt that are designed for a gas check. I paper patch those (without gas check) and they are quite accurate out of the Marlin. .454" as cast & .458" with paper.
My guess is using any shorter brass (45-70 or 45-90) will cause leading and I might have to clean the chamber between shots to maintain accuracy.
So with that lengthy answer, I am still in the market for 45-120 brass. Failing that, I may look into having the barrel set back to 45-70. My favotite gunsmith recently had a heart attack, so I'm not in any hurry to go that route.

 

Another note, I have a mold for a hollow base bullet. May try that, and see if it helps or hinders accuracy.

 

Found actual 45-120 brass! Bought 25 from a nice gent in Colorado, all new Norma brand. Should have bought more, but money wasnt available at the time. I since bought another 25 from the same source. 50 should be a lifetime supply.
Found I only had enough 2fg black powder to load 3 rounds. Someday I'll learn to think ahead! I do have 3fg powder for cap & ball revolvers, unsure how it would work in a rifle in large doses.
Supply of Schuetzen & Swiss 2fg enroute from Buffalo Arms. Should be here later this week. Then I can finally load up enough to make a range trip worthwhile.
Still haven't located anyone else foolish enough to have a 45-120, so can't get advice from an actual shooter. I'm relying on information from Mike Ventuino & Paul Mathews books. My shooting buddy (I use that term loosely) keeps telling me "should have bought a 45-70".
I'll post shoting results here when available.

 

.45-120 Nitro Express - AmmoGuide Interactive

The first SERIOUS reloading manual on the web.

ammoguide.com

AmmoGuide Interactive

The first SERIOUS reloading manual on the web.

ammoguide.com

I thought about rechambering my Buffalo Classic for 45-120, then I thought 450 #2 Nitro Express. Then I sobered up. But if you decide to hunt elephant or Cape Buffalo, you are all set.

 

No Ephalumps or Buffalo in SC, except the zoo. This is meant to be a toy, rather than serious hunting. I have other, much lighter arms to carry afield. Loading today with fresh shipment of black. Range time next week.

 

I've been told the 120 case tends to respond better to 1Fg or 1.5Fg and accuracy degrades with FFG and smaller. I just received a few cases, but I'm still waiting on bullets to load before I can experiment.

Where did you get your cases? I found some in Australia, which wasn't cheap and turned out to be Bertram not the Norma brass that was expected...

 

I got lucky and found someone in Colorado who had 100 new Norma brass. I initially ordered 25, as his price was steep, but...
Once received I decided to bite the "brass" and buy another 25, as that's all he had left. The brass was listed on Gun Broker, so youmight have to haunt that site for brass.
50 should last my lifetime with this beast. I have loaded 20 using 2fg Schuetzen powder and 385gr FN cast bullets. Used 100 & 110gr powder (by volume). I wanted a relatively light load to start.
I have yet to go to the range as it's been too D*mn hot, 99 yesterday, upper 90's for the past 2 weeks. I'm in South Caolina, and never thought it would be hotter than Florida when i moved here. Supposed to be "cooler" this week, 90 for today. I'll postresults once I get to shoot.
Good luck in your brass seach. Make sure you get 45-120 Straight and not any of the Nitro Express brass. I made that mistake.

 

By the way, you might want to invest in casting your own bullets. That's what I do, everythng from 38/357, 41, 45 for handgun and 30, 35, & 458 for rifle.