Sharps 40-70 SBN

[bigted]

So have had this old barrel for awhile. It is a "ol Reliable" by C Sharps on top flat along with 40 cal. Under the forearm area is stamped a wolfs head and stamped "Shilo Sharps co"

My conundrum is the chamber. It is very close to a 40-70 Sharps bottle neck but a little off.

I lubed and pounded a 45-70 into the chamber to get a likeness but it was just a bit short. Next I cut down a 45 basic cartridge ( picture ) and messured it out. Here is the basic messurements from the pounded 45 basic cut to 1.150 which could be a bit short yet.

Length ... 2.150 , could be as long as 2.250.
Neck length ... .475
Body length ... .1.560 ish
Neck taper length ... .100 ish
Neck OD ... .442

So as you can tell, it is close to the 40-70SBN.

Next question ... wonder why those loading dies are so very expensive.

Would like to have a no powder or primer reloaded ( or at least sized ) case in 40-70 sbn to try to chamber and see how it chambers.

[Chill Wills]

How about a hot glue chamber cast for a quick clue on length? I would have to look up what your measurements are but not close to the book just now.

[DocSavage]

You might have better luck with Cerrosafe from Brownell's to make a chamber cast the stuff is a little pricey but it will give you better results than pounding brass into submission.

[Wayne Smith]

And cerrosafe is re-meltable and re-useable - a major advantage. I second that recommendation.

[ragnar]

How about a hot glue chamber cast for a quick clue on length? I would have to look up what your measurements are but not close to the book just now.

Exactly what is this and how is it done? Will paraffin canning wax yield good chamber casts?

[upnorthwis]

Candle wax works too. Knocks out easy, is harder than you think, and measures well.

[bigted]

Now THAT I can do! Wax is rite there in the shop and I have the means by which to both heat the barrel for a good cast ... and melting the candle wax.

I will attempt this tomorrow ... I hope.

[country gent]

We used wax and clay for measuring in the shop. The reason dies are so expensive is the low numbers sold and needed, its just not feasible to make a run of them. That wouldn't be a bad lathe job to modify a 40-65 straight die for or any smaller existing die would be a pretty straight forward job to lathe bore and polish. given the chamber cast or a fire formed case. ( size a couple cases down in 40 65 die or neck die enough to chamber and fire form to match chamber. This would give useable dimensions to bore the die to. Not having a reamer makes it a lathe job

[ndnchf]

Don't let anyone tell you a .40-70bn won't shoot well. I shot this a number of years ago when my eyes were better. Not high level competition worthy, but not bad for a weekend plinker. Good luck with yours.

[bigted]

Well all I have is this ol barrel. BUT ... I have a couple actions I am thinking about putting it on. If ever I get a for sure on the chamber. Could be that I shorten it enough to rechamber for a proper chamber.

Ruger 45-70 is one old donner.

Old military 43 spanish Roller is another thought.

OR ... my Shiloh chambered in 45-3.25 is another thought ( this SOB kills me with every shot AND is hungry for lead AND powder ).

Bore on this barrel is spotless and in a #10 shape. Shame to not use it on something. 40-70 Sharps bottle neck seems a very good chamber and prolly fit my needs very well.

[bigted]

This is the wax cast with Gulf wax and orange crayon for color.

[bigted]

Here are the exact measurements.

... 2.175 overall chamber length
... 1.435 body length to shoulder
... .120 shoulder length
... .490 neck length
... .150 free bore length
... .065 rim thickness
... .613 rim diameter
... .508 body diameter at rim
... .485 body diameter at shoulder
... .404 groove diameter

So there she is ... these are actual measurements.

What say ye.

[Hiwall55]

Pretty nice chamber cast Ted.

[beltfed]

I don't know for sure, but it is possible the candle wax cast
may have shrunk a bit after cooling. So, Be careful how you use those dimensions.
As another person said, Cerrosafe is made such that it comes back to actual "as cast"
dimensions 1 -1 1/2 hours after casting the chamber
beltfed/arnie

[bigted]

I was interrupted in my explanation. These measurements are off from my " handloaders manual of cartridge conversions " from the 40-70 SBN cartridge drawing and measurements. It is close but off in critical dimensions ... length for one, neck length for two, neck diameter for a third.

My measurements were taken right after exiting from the barrel ... read still warm. However after some 6 or 7 hours, I went out and took comparison measurements and after this amount of time, they stayed within .001 inch of the warm measurements.

Still n all some measurements are off by .100 for instance on cartridge length, and head diameter by .050.

Guess I could have it shortened and re-reamed but ... if going to this length ... I would have a hard time not re-threading to Ruger threads and reaming a chamber to 40-65 Winchester as I am already set for that in my old sporting Remington roller.

[Lead pot]

Arnie wax will make a very accurate chamber cast. I compared the wax cast with cerrosafe and I can't measure any difference with the micrometers I have between them. Wax tends to shrink on the inside of the cast. Yes you need to let it cool before driving it out.

Attachment 245511

[bigted]

Lead pot, glad you wondered by. Can this be a chamber differing from OEM by ol Wolfgang? It is a Wolfgang barrel ... or Shiloh barrel for a Wolfgang rifle.

Nother question is ... could this be a muffed chambering removed from the trash heap and somehow wondered onto the open market?

Definitely sharps threads and it does have the Wolfgang free bore.

[sharpsguy]

A friend of mine has a 40-70 Sharps BN. I have a Sharps 40-70 straight, and a Sharps 40-65. All three of the rifles are Shilohs. If I could have only one caliber of the three, it would be the 40-65, hands down.

[bigted]

A friend of mine has a 40-70 Sharps BN. I have a Sharps 40-70 straight, and a Sharps 40-65. All three of the rifles are Shilohs. If I could have only one caliber of the three, it would be the 40-65, hands down.

I agree 100 %

[Lead pot]

Ted I don't know anything about Wolfgans rifles. I once ordered a .50 but backed out because of the long wait. But the freebore and the what looks like a 45 degree transition into the throat was common with his rifles.
The only experience I have had with a .40 BN was a old Roller a long time back.
Your chamber length sounds more like a .40-50 then a .40-70 that was 2.25" also the rem neck diameter was was larger than the Sharps.
But I'm working on memory Ted, but your chamber closer matches a .40-50.
Kurt