Don’t own one but did put a couple rounds through a Shiloh Saturday.  I think there was a thread on the 50-140 a few months ago where they did some discussion on accuracy. My opinion is after shooting one….I don’t know how anyone could get a good group with that recoil.  But, then I am a recoil wimp!  Sure could ring steel with it though.
Bob

An aquatince of mine had one many moons ago. He didn't want to use black so he loaded smokeless ( don't know what) behind a 550 grain bullet and no filler.  Almost every other round  hang fired until one he counted to twenty without the boom so he thumbed back the hammer unlocking breach just as it decided to go off. It spit hot gas and brass shrapnel all over his arms,  chest, and face. Thankfully he had glasses on which saved his eyes.  Big cases with smokeless is not a good idea. There is a reason Shiloh advised against it. I saw it first hand and it wasn't pretty.
Flatlander

I had a C. Sharps in 50-140.   It shot it with 140gr of powder and a 698gr Creedmoor bullet.  It was way too much gun for me to shoot well.  As I've aged I learned a few things along the way, often the hard way 

Chris.

I bought my Sharps 50-140 new in 1984. I was still in my late 20’s living in Nevada. I used it for hunting big mule deer. I loaded it with an Elmer Keith load of 130gr. 3f, 10gr. Shotgun powder over the primer, 3/8” grease cookie over a card wad, and a 725gr. Home made paper patch bullet. The rifle was the sporting configuration. It was a great hunting rifle, never had to shoot it more than once at anything! I still have the rifle….
Side note: I shot at a big buck mulie one time in the mountains of Nev. he was standing on the back side of a big Ponderosa pine tree. I fired, the bullet passed clean through the tree and the deer and kept on going… rifle never was lacking in power!
Tom

...

Several years I assisted running target rig at the Vintage cups. Two rifle classes stalking and stopping. Stopping the biggest guns possible single shots and doubles. African rife calibers mostly some Buffalo guns too. 

They were only shot offhand crossing and charging targets crosser diagonal 25-50 yards depending were they took the target  The charger from 50 yards out to were shooter had to step aside or be hit by the charging target. Third target at 50 yards turned, from edgewise to full face to edge in a few seconds 

Watching many, my observation, some could shoot them very well for a while putting shots in a 12 inch circle . Some could go longer, others had the worst flinch you could imagine. We even had a guy let go of his rifle and it went flying after the first barrel fired. 

Groups ? Hitting a bucket offhand 25 yards is about as good as I would expect most people could do. There are exceptions Malcom McGregor could shoot big stoppers all day with no ill effects. He had one of the most desirable single shots I have ever seen. Holland and Holland falling block re stocked by Griffin & Howe to Elmer Keith’s specifications, Keith’s personal African gun.

Chris Christensen ASSRA Schuetzenmaster at Columbia was one of the better shooters with a 12 Gauge Rifled hammer double using BP and a single round ball. Less recoil than most, met the stopping rifle rule & very accurate. Chris won several events with it.

My favorite as a shooter would have been Chris’s rifled 12 but Elmers single shot would have been the bragging gun.


Boats

I have a C sharps that I bought in .50-140 it was very hard to get it shooting tried everything I could think of it came with. Two molds a Lyman  450 gr. And a RCBS 512 gr. I believe it shot ok with smokeless but not black . Finally I try some Buffalo arms 650 gr and some 700 gr. bullets and 130 gr. Of Goex ctg and my 200yard targets now had groups on them instead of patterns but I started getting a very bad pain in my right eye and said goodbye to the .50-140 now it’s a tack driving .40-65. Also I tried a lot of reduced Blackpowder charges with fillers that was a complete waste of time.

I have a .50-110, had another one I sold here to I can't remember who a while back.  

At the risk of getting that same "Big difference between a 50-90 and a 50-140 in internal case capacity", I'll say that it's not an unreasonable rifle to shoot.  My standard load is 114 of Goex express, and a 740 grain bullet.  

I don't shoot it in preference to my .45-90's, only tried to shoot it in a match once, at Alliance NE for the 1000 yard.  In practice, I found my bullets wouldn't chamber reliably, so I shot the .45 instead.  I should load up a couple hundred rounds and try it out one of these days.

A lot of people have trouble handling even lighter recoiling rifles, particularly if they see the big case first.  One of my favorite rifles is my Fields Patent .450 3- 1/4".  I used to take it to the range with 20 loaded cartridges (all the brass I used to have).  I made up a charging elephant full size target that we'd put up at 30 yards, where the rifle is regulated to.  We'd all step up to the line, bring up the rifle and take one snap shot offhand.  Walk down to the target and sign the bullet hole.  Closest to the 2" kill zone took the target and bragging rights home.  A lot of onlookers at the range wanted to try it.  I'm amazed at how many missed the 4 foot elephant head target altogether, at 30 yards.  I could usually put the shot within or very close to the 2" kill zone, as could a couple other of the regulars.  The .450 is really quite tame, it uses a 360 grain or so bullet behind about 105 grains of 2f.  

Black powder works ok. Problem start when someone loads too small smokeless charge in cavernous case. .
Flatlander

Too large area with too small powder charge causes erratic primer flash powder ignition and pressure spikes. Powder lays in bottom of case with empty air space. If you load smokeless in any of the old large black powder cases I wish you the best as I have seen bad things happen. I'll say nothing more. No arguments.
Flatlander

Cbashooter wrote on Nov 23^rd, 2023 at 1:24pm:


When I boke down loaded .50-140 rounds I got with my Sharps that were loaded by Eldorado Custom Loading in Boulder, Nv. back 30 years ago I found rolled up tissue paper filler stacked above the charge of 4198 powder! I was a bit surprised as I avoid such things, and wondered how they might have shot? But I was too scared to try them as the data showed the load to be 1650 fps with a 678 gr. bullet, and didn't appeal to my shoulder, or my Sharps.