Pretty Sure My Sharps Isn't a 45-120

[harringtondav]

Per my post from a few years ago I'm still working on firing my Dad's 45-120. ...at least he thought that's what he owned based on his meticulous 1960's notes.
Taking his word as gospel I ordered some Bertram brass and loads. ....got tired of finding someone who could get Norma brass.
Empty brass fit just fine. Loads bottom out long. I measured the distance from the receiver face to the start of rifling, not the counter bore face. Roughly 3.28". The cartridge is about .68" long, measures 3.65" long.
Clearly the gun is chambered for a shorter cartridge. Please help and tell me the correct size.
Thanks, Dave

311998
311999

[Don McDowell]

Might want to get some cerrosafe and do a chamber cast to measure the chamber length and throat length and diameter. Sounds like it may be a 2.6 or maybe a 2 7/8 chamber, but before you start sawing on the brass some good measurements need to be done.

[harringtondav]

Thanks DM. I bought a Lyman die set for the 45-120. Do you know if the brass taper angle is the same with the shorter brass?
Assuming it is, and the neck expanding and seating die can adjust down I'd like to use these dies once I figure out what I have.

[Castaway]

Don, I’d normally defer to your wisdom, but why wouldn’t the rifle be chambered in 45-120 if the brass fits? Depending on nose shape, the bullet may have to be seated more deeply into the case. If I load a Lee 500 gr Govt bullet in my Shiloh Sharps, the bullet only has 0.386” sitting above the case mouth. Any more and it just won’t fit

[HWooldridge]

That silver scratch on the bullet nose may be where the bullet is hitting the beginning of the rifling. You might need a smaller profile bullet.

[harringtondav]

I used a bore light to look at the chamber. I noticed the machined diameter where the cartridge centers (throat?) ended before the rifling, with a recessed clearance between. The cartridge length is 3.24", just short of the dist to rifling of 3.28". I'd have to seat the bullet nearly flush to close the breech.
I just calculated the distance from the rifling marks on the bullet, minus the distance it was long and came up with 2.63" from brass face to rifling.
Maybe that length corresponds to the correct cartridge size.

[scattershot]

“Empty brass fit just fine.”

Seat your bullet deeper or use a more tapered ogive.

[Woodtroll]

Comparing the two photos, it looks like the "loaded" cartridge case is sticking out quite a bit more than the distance from the cartridge mouth to the scuff on the bullet would imply. From your measurements and the fact that the empty brass slides all the way in, I think the brass matches the chamber length.

Is it possible that the chamber is a tight one and/or the bullet is oversized, so that the brass is jamming in the chamber before it is fully seated?

Good luck! I hope you get her shooting!

[indian joe]

“Empty brass fit just fine.”

Seat your bullet deeper or use a more tapered ogive.

If you cant get a chamber cast done - bell (flare) the mouth of an empty case and load it all the way home - might tell you something useful?

[Don McDowell]

Don, I’d normally defer to your wisdom, but why wouldn’t the rifle be chambered in 45-120 if the brass fits? Depending on nose shape, the bullet may have to be seated more deeply into the case. If I load a Lee 500 gr Govt bullet in my Shiloh Sharps, the bullet only has 0.386” sitting above the case mouth. Any more and it just won’t fit

Because it’s possible the sized brass coul fit right up the throat
It is possible to load a 2 7/8 case with 120 grains of powder if only going by load data that could be what he called 120
Chamber cast is the only way to know for sure

[Don McDowell]

Dave it is does turn out to be a 2 7/8 your dies probably work ok
But if it’s 2.6 either ha ego get another set or have your dies shortened

[Lead pot]

Do a chamber cast. That will answer most of your questions.
If you don't have cerrosafe melt down a candle and pour it in the chamber. Lightly oil the chamber push a rolled to patch or what ever ahead of the chamber and pour in the wax. let it cool and push it out with your cleaning rod with a patch on the jag.
This will let you measure the chamber.

[Kenny Wasserburger]

Measure the outside diameter of your loaded cartridge at the case mouth.

This will tell you much also measure the diameter of your bullet just ahead of the case mouth. If it’s over .450 you have bulged the bullet while seating the cartridge. A common nob mistake when first learning to load this lead bullets. You’re compressing the powder with the bullet upsetting it.

If an empty case 3.25 long fits the rifle. Then you’re are doing something wrong when loading the cartridge.

Kenny Wasserburger

[Minerat]

Why not insert a boolit in the chamber until it just touches the lands? Then use a caliper to measure from the bullet base to the breach face. Then add that measurement to the boolit length and that would give you the max cartridge length. Which could be compared to known measurements for the 120 to see if it matched.

The true measurement you need is from the first drive band to the base of the case but having MCL you could be close enough to get you an answer..

[harringtondav]

Cerrosafe looks easy enough. Will a compressed wad of cotton or cleaning patches work to block the bore?
But I think I already know the answer. I dug out an old box of 45-70 Govt. cartridges. 2.535"OAL. ...close to 2.6"
Second pic shows the 45-120 from rifling marks to breech face against 2.875". Looks like a no go.

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312015

[Don McDowell]

Yes a flannel cleaning patch and a Colton ball about an inch into the rifling will work
Kenny and Mine Ray have both given some good suggestions to look at doing before the chamber cast
But with no chamber or caliber markings on the barrel a good chamber cast will answer a lot of questions
Is that an original rifle or something your dad rebarreled?

[semtav]

Quickest way to find out. Is take a piece of brass that fits in it, fill it full of black powder, put a couple wads on top and fire it. You should be able to see what's going on then.

Or smokeless and cornmeal

[harringtondav]

Below is a scan of his notes on that very topic. Seems he owned a "Franken-Sharps" and knew it. But he was sure it was a 45-120.
He dabbled with the gun Nov and Dec 1963. He noted he had trouble getting the breech to close with Nonte-Taylor cases. He cast up Lyman 457191 bullets, but couldn't get the breech closed. His mold for the heavy patched bullet is also shown.
His last note in 1983 was on making grease lubricating patches. The gun stayed in the closet until I cleaned out his house in 1992.

If it turns out be a 45-70 all isn't lost. Those 45-70s are likely smokeless, but I can reuse the brass and bullets with the appropriate black powder charge. ....I'll be back for advice on those loads if the time comes.

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312042

[Don McDowell]

I'll about bet it has been chambered for the 3 1/4 case at one time, but it was with the tight paper patch chamber. Any bullet over .450-454 diameter isn't going to chamber. Unless it's one of the really short 300 gr express bullets.
You might see if you can get ahold of some .444 slicks and wrap them in 8 lb paper, if you don't have his mold. Over 120'ish grains of 1f powder a .060 fiber wad, a 1/16 grease cookie and a thin wad punched from wax paper or a playing card.
Neat old rifle to be sure.

[harringtondav]

I've made more measurements and assumptions on this. Please advise if I'm fixing to blow my face off.
-Chamber appears to accept a 45-90 WIN.
-My 45-70 Govt. loads are nearly ready to be made into 45-90's. The difference seems to be 20 grains more BP and seating the bullet to a 3.3" overall cartridge length.
-I can verify by pulling a bullet, resize and expand the empty case neck, and loose assemble to 3.3" If the breech block closes and a 3.3" cartridge comes out I'll assume I have a 45-90 FrankenSharps.
-45-90 original bullet was 300 grain, mine are 405 grain. Am I in the danger zone using this bullet?. On another forum shooters go over 500 gr.
-Assumption is my cartridges are BP which can be reused. I'll weigh on disassembly. 70 grains will be BP, less will be suspect.

If all these pass your sniff test, I'll have more questions before I try firing the beast. Paper patch vs. grease. Bullet size for either, etc.
Thanks, Dave

312508

[country gent]

I believe the 45-90 case is 2.4"long not the 2.1 of the 45-70. also check your twist rate. A lot if the reproductions were 18 twist good for 500 grn. Some are 1-16 and will handle even longer bullets.

I have a C Sharps hepburn in 45-90 with 2.4 inch starline brass I get around 82 grns under a 550 grn bullet. Nw manufactured brass sis solid head and thicker than the older id meaning less powder capacity.

[Gunlaker]

I'd still do a chamber cast. There could be any sort of custom chamber on that rifle. A good chamber casting will tell you not only what cartridge the rifle is chambered for, it'll also give you some clues as to what bullet it'll shoot well. You can easily get freebore diameter & length plus leade angle. The chamber casting is going to be a lot cheaper than buying several molds. Plus you can re-melt the chamber casting and reuse it for another rifle at any time so it's nearly free. Before I did my first casting I was resistant to doing one but then I found out how easy it is and how useful it is. I've done more than a dozen of them since starting.

Chris.

[harringtondav]

Thanks, and dang. My brass measures 2.1".
But all is not lost. I have enough 45-70's and 45-120's to swap for 2.4" brass.
The copper mold below was my Pop's. .441" dia, 1.5" long, 525 gr. ...thinking paper patch (?).
So it looks like I may be able to recreate your recipe. I believe my barrel is original, but I don't know the twist. 16# rifle with a heavy octagonal barrel.
Thanks again.

312515

[Don McDowell]

The 45-70 cases won’t stretch
The worst that can happen is you’ll lead the heck out of the barrel or possibly ring the chamber if you fire enough rounds

[Huvius]

I'll about bet it has been chambered for the 3 1/4 case at one time, but it was with the tight paper patch chamber. Any bullet over .450-454 diameter isn't going to chamber. Unless it's one of the really short 300 gr express bullets.
You might see if you can get ahold of some .444 slicks and wrap them in 8 lb paper, if you don't have his mold. Over 120'ish grains of 1f powder a .060 fiber wad, a 1/16 grease cookie and a thin wad punched from wax paper or a playing card.
Neat old rifle to be sure.

THIS^^^

Your mold will patch up to .449-.450" and likely slip nicely into the bore while your 120 case sits nicely in the chamber - just as it was intended.

I'll throw my hat in for a chamber cast as well. I wouldn't mess around with any other paths until you do that and know for sure what the chambering is.

[Bent Ramrod]

Looks like you have a Yankee Specialty Co mould for a .45 paper patch slug. Four wraps of 0.002” thick tracing or vellum paper should bring the diameter up to 0.449” or so for a slip fit into the bore.

Any chance the barrel is chambered for the original Sharps 2-7/8” case? That was sometimes referred to in the old days as “.45-120” because with sufficient compression, 120 gr of powder could be stuffed into the case with a card wad and a bore diameter paper patch boolit barely seated into the case mouth. The normal loading was 110 gr or so, however.

Winchester treated the 2.4” case as an Express round, with a slow rifling twist to shoot short 300 gr boolits for a flatter trajectory at the typical 125-yd+/- blackpowder hunting ranges, calling it the “.45-90 WCF.” Sharps made their rifling twist quicker for this case to suit a longer boolit in the 425-500 gr weight for better stability and penetration at long ranges, and kept the shell length description. Up to 100 gr or so of powder could be put into this length case.

I would go along with the general recommendation for a chamber cast. Given the scarcity of long .45 cases nowadays, a couple ounces of Cerrosafe (which can be melted out of the chamber if the casting sticks along the learning curve, and can be recast over and over and saved for the future) is a cost effective alternate to possibly messing up cases in trying to figure out what you have.

[harringtondav]

Yes. I stopped beating around the bush and just now ordered Cerrosafe. BTW Bolton Metal products was 1/2 the cost of Brummels.
After I get a good casting I'll know for sure the chamber dims. I wasn't aware that a 2-7/8" existed. I'll report back with the dimensions
I have (20) 3-1/4" cases that are basically boat anchors, so I can cut them down to match what I find in the casting.

I plan on getting 1" or so of rifling so I know true bore size.
This gun has five groove rifling. Not the easiest to measure dead nuts accurate. Is there a stickey on the forum that explains how to measure bore size with an odd number of grooves?

[harringtondav]

..bad post. ...meant to quote another.

[harringtondav]

Yes a flannel cleaning patch and a Colton ball about an inch into the rifling will work
Kenny and Mine Ray have both given some good suggestions to look at doing before the chamber cast
But with no chamber or caliber markings on the barrel a good chamber cast will answer a lot of questions
Is that an original rifle or something your dad rebarreled?

I'll be pouring a chamber casting once the Cerrosafe comes.
I want to follow up on your ref to Kenny and Mine Ray before I try this. ....who are they, and how do I find their writings?
Thanks.

[John in PA]

When you get around to doing the chamber cast, use Duxseal or modeling clay to create a dam around anything you don't want metal to flow into. Once it solidifies in your extractor groove or lever spring mortise, it could be a bugger to get out. When in doubt, dam it! A small empty soup can with a spout bent into the lip works just fine to melt in and to pour.

[Gunlaker]

One other suggestion for pouring cerrosafe is to take a coke can and cut it in half. Bend it to make a pouring spout. I preheat the barrel around the chamber until it is hot to the touch with a heat gun. I also use the heat gun to melt the cerrosafe in the coke can. I plug the barrel with a few patches maybe 1" ahead of the chamber end.

Also, the stuff solidifies pretty fast and then starts expanding a little as it does. I'd advise not listening to the instructions and us a cleaning rod to knock the casting out maybe 30-60 seconds after it's solid.

There are formulas to convert cerrosafe casting dimensions to actual dimensions based on the casting age.

Chris.

[harringtondav]

When you get around to doing the chamber cast, use Duxseal or modeling clay to create a dam around anything you don't want metal to flow into. Once it solidifies in your extractor groove or lever spring mortise, it could be a bugger to get out. When in doubt, dam it! A small empty soup can with a spout bent into the lip works just fine to melt in and to pour.

Thanks, I made the chamber cast shown below using your method....almost. I forgot to dam the extractor. But with an O ring pick and a little direct heat gun directly on the extractor I got it cleaned out.

I sanded a 1/2" fluted dowel down until it was tap snug in the rifling at the end of the chamber. This worked well.

I've cut a 3.25" case down to the 45-110 2.875" length, loose fit the original bullet to the 3.36" spec OAL.

This leaves me with another question: The bullet will now have a .300" 'jump' to contact the rifling. Is this OK?

Pic shows an original 45-120, the chamber cast, and a 45-70 Govt for reference.
326027

[harringtondav]

When you get around to doing the chamber cast, use Duxseal or modeling clay to create a dam around anything you don't want metal to flow into. Once it solidifies in your extractor groove or lever spring mortise, it could be a bugger to get out. When in doubt, dam it! A small empty soup can with a spout bent into the lip works just fine to melt in and to pour.

Thanks, I made the chamber cast shown below using your method....almost. I forgot to dam the extractor. But with an O ring pick and a little direct heat gun directly on the extractor I got it cleaned out.

I sanded a 1/2" fluted dowel down until it was tap snug in the rifling at the end of the chamber. This worked well.

I've cut a 3.25" case down to the 45-110 2.875" length, loose fit the original bullet to the 3.36" spec OAL.

This leaves me with another question: The bullet will now have a .300" 'jump' to contact the rifling. Is this OK?

Pic shows an original 45-120, the chamber cast, and a 45-70 Govt for reference.
326027

[kootne]

Those old chambers were not cut the same as what we consider "best practice" 150 years on. Here is a photo, cast from a Sharps 1874 Factory conversion from a percussion carbine to a "Business Model" configuration. I have seen similar chambers in 1878 Model 45/70's. The chamber cast is marked with a scribe mark on the red felt tip marker spot. The scribe mark is 2.03 from the front of the rim to show where a 2.1" case would be in the chamber. It is .325 to the beginning of rifling from that scribe mark. This chamber would freely accept a case of 2.3" long based on measurements of this casting
326044.

[elmacgyver0]

If you are using powder coated bullets and they are bore riders, that could be the issue.
I have this problem with my .45-70s.

[harringtondav]

If you are using powder coated bullets and they are bore riders, that could be the issue.
I have this problem with my .45-70s.

My guess these are powder coated, or some other lube coating. Chey-Cast 300 gr.
Not sure what you mean with a bore rider bullet. .457" dia. You can see the rifling bite marks on the nose.
When seated to length the same amount of bullet exposure as with the 45-120 loads. Approx .4" of a .76" bullet.

I've read bullet jump affects accuracy in smokeless rifles. I'm not too worried about this, but I am worried about safety and excess leading.
Do you think the .3" jump will be OK?
326050

[craneman]

Looking at your photo I'm not sure you cast the entire chamber. I like to have at least a 1/2"-3/4" of rifling on my casts to be sure I have a complete picture of the end of the chamber and leede. If you are short of the end you still won't quite know what you have or what bullet might work best in your rifle as you want a bullet that fits a fired case mouth and the throat-leede.
Todd