Shiloh's 40-70 SS reamer - questions

Ask Shiloh questions about your Shiloh Sharps Rifle.

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august west
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Shiloh's 40-70 SS reamer - questions

Post by august west »

I have a rifle ordered in 40-70 SS and have secured a large quantity of new Jamison 405 Winchester brass. I'm going with this brass partly because I didn't want to use stretched 30-40 brass, and partly because I just happened on this by good fortune. I was prepared to have a custom reamer made if needed to use this brass (as others have done with the 405 Hornady brass - thus the "40-70 Hornady" reamer at Pacific Tool). But as it turns out, this brass is exactly, basically, 40-70 SS. It matches every measurement (except length of course) and is much more like 40-70 brass than it is 405 brass.

I have some questions for Kirk about Shiloh's standard 40-70 SS chamber reamer:

1. What is the case neck diameter?
2. What is the base diameter?
3. Is there free bore on the reamer, and if so how much?

The base diameter on my brass is .04525 - .04530.
The neck diameter is .0423-.0425.
The rim thickness measures .0685 - .0710.
My case neck thicknesses varied .0085 - .0094, new unfired brass.

These cases fit PP bullets perfectly - the bullets miked at .401-.402 over the paper.

These measurements are identical with all the info I've been able to find on the original SS case, and matches the thicker rim used by BACO for their Shiloh-specific reformed cases, where the rim is swaged to increase thickness to .068+. I realize that if I have some thick rims I may need to dress them down slightly for the block to close.

I'd like to use Shiloh's stock reamer if possible. I'll get a custom reamer if needed but it's looking like I may not need to. I do want to use the 7 degree leade that several have recommended - I'm assuming this is a feature of the stock reamer?

Thanks very much for any help.

Ryan
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Re: Shiloh's 40-70 SS reamer - questions

Post by Kirk »

Neck = .432"
Base = .458
Depth = .070
Lead = 2.5 degree with no free bore, the 7 degree reamer is used to eliminate the 45 degree case stop and blend into the 2.5 angle.

We can also use the PP reamer but then you are limited to PP bullets only. Neck dia. will be .423"

Kirk,
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august west
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Re: Shiloh's 40-70 SS reamer - questions

Post by august west »

Thanks Kirk! Fast reply.

(Disregard my question about the PP vs. standard reamer - I understand it now.)

This is a dedicated PP rifle, as far as I'm concerned. It might be fun to have a GG load, if that worked out, but my first priority is PP.

Thanks again.
Ryan
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Re: Shiloh's 40-70 SS reamer - questions

Post by Kirk »

I really hated seeing Jamison go down, he had some pretty nice brass.
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august west
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Re: Shiloh's 40-70 SS reamer - questions

Post by august west »

This brass is really nice - very consistent and very heavy. I also have a few Bertram cases and just holding them in your hand you can feel the obvious weight difference. It's gonna be hard to get 70 grains in there probably but that's fine.


Kirk - any rough idea when you will do round barrels next time, for this order?
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Re: Shiloh's 40-70 SS reamer - questions

Post by Randy Bohannon »

I have no problem getting 70 + grs. of powder in my Jamison 40/70 SS brass with DDPP greaser or PP. After playing with the 40-70 SS for long enough to know I only want one and have a 77 on order and scheduled for another 40-70 SS , it will get changed before being built.
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Re: Shiloh's 40-70 SS reamer - questions

Post by august west »

Good to know about the capacity.

Are you saying you don't like the cartridge? Lots of people have had great success with it. Was it hard to get it shooting well in your rifle?
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Re: Shiloh's 40-70 SS reamer - questions

Post by Randy Bohannon »

Temperamental tyrant of a cartridge,knowing what I know now I would get a 40-50 BN and not have the brass issues . 45-70 is a hands down winner for day in and day out consistently being accurate I cannot say the same for the 40-70 SS. I have spent equal time with both in a Shiloh Sharps 1874, I have three moulds for the 45-70 and seven for the 40-70 SS,consistent accuracy is elusive except under perfect conditions and not all the time. Is it a 40 cal problem ? I don’t think so ,we are not playing with original cartridge dimensions and I think the transition to what we use today is a temperamental tyrant.
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Re: Shiloh's 40-70 SS reamer - questions

Post by rdnck »

The ODGs had a way with words, and you often have to read between the lines to understand what they really meant when they wrote something. They were also often polite with their discourse to a fault. Consider what Harry Pope had to say about a 40-70 Straight. He opined that the 40-70 Straight "was an accurate cartridge " if a proper load can be found". The words IF A PROPER LOAD CAN BE FOUND say an awful lot, and in our desire to shoot the cartridge and our personal ego and belief that "I can make it shoot,even if the other guys can't" causes a lot of us to get blinded by the reality of the cartridge. I include my self in this group, and my 40-70 Straight would have gone down the road a long time ago if it wasn't the prettiest rifle I own. That , and the fact that on its' good days, it is damn near a magic wand. Shoot straight, rdnck
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Re: Shiloh's 40-70 SS reamer - questions

Post by rdnck »

The ODGs had a way with words, and you often have to read between the lines to understand what they really meant when they wrote something. They were also often polite with their discourse to a fault. Consider what Harry Pope had to say about a 40-70 Straight. He opined that the 40-70 Straight "was an accurate cartridge " if a proper load can be found". The words IF A PROPER LOAD CAN BE FOUND say an awful lot, and in our desire to shoot the cartridge and our personal ego and belief that "I can make it shoot,even if the other guys can't" causes a lot of us to get blinded by the reality of the cartridge. I include my self in this group, and my 40-70 Straight would have gone down the road a long time ago if it wasn't the prettiest rifle I own. That , and the fact that on its' good days, it is damn near a magic wand. Shoot straight, rdnck
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Re: Shiloh's 40-70 SS reamer - questions

Post by august west »

We'll see. I've got the brass now and I like a challenge. Lots of folks here swear by this round, some swear at it. Every cartridge has its lovers and haters.
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Re: Shiloh's 40-70 SS reamer - questions

Post by Don McDowell »

Usually hesitant to stay out of these type of threads...
I would urge you not to go with a "paper patch" chamber and just go with the regular chamber. The standard chamber will give you a bit more flexibility in bullet selection, and as tight as the Shiloh chambers are resizing after firing may or may not be necessary, and that will give you the ability to go with a fatter slick with thinner paper, and may prove to be the thing you need to get the most out of an extremely temperamental cartridge.
My 40-70 will shoot 2 bullets and 2 bullets only with any sort of consistency, and both of those are patched bullets a bit more in diameter than some would suggest.
I find the case to also be pretty picky about powder charge, interestingly enough both bullets that work in my rifle altho 40 grs weight difference use the exact same powder charge and wad stack.
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Re: Shiloh's 40-70 SS reamer - questions

Post by august west »

Don - thanks - I am in fact going with the regular chamber. I've been told there is no "accuracy" reason to go with a PP chamber. I would also like to work up a rough-use greaser load for hunting - something I can shove in a belt or coat pocket without worrying about the bullet falling out and the cartridge disassembling. The Jamison 405 brass seems to be very consistent and is identical to 40-70 SS brass down to the .001 - it's thick and heavy and I might have trouble finding a bullet that would seat in a tight Shiloh PP chamber. I'll have 500 new unfired cases - I think that will be all I'll ever need, or hope so anyway.

I'm relieved that it looks like I can use the standard reamer but will size and mike some cases today and see how they are after they've been run through dies. I'm hoping however to be able to reload cases unsized. Arnie S. is helping me through this process since he's done the same thing himself - no sense reinventing the wheel.

Just curious - what are your two favorite .40 bullets, Don?
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Re: Shiloh's 40-70 SS reamer - questions

Post by Don McDowell »

The two bullets that work consistently well in my rifle are the Baco .400360 and a dual diameter bullet Brooks built for me with a .400 base
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Re: Shiloh's 40-70 SS reamer - questions

Post by bruce m »

popes comment begs some questions like
was he talking about black powder, smokeless powder, duplex loads, breech seating, greaser or pp, and so on.
was he talking scheutzen shooting (we could be forgiven for thinking so).
accuracy levels compared to what? and how much difference.
today the 284 winwill outperform the 6mm ppc from 300 to 1000 yds, but can't touch it at 100 and 200..
which is the more accurate?
if pope was talking breech seating, the 40/70 case at 200 yds and less will not beat some others.
too much recoil for a start.
how can it have been so highly regarded in the day, way above the 45/70, for mid range.
they shot pp bullets dirty and got good results.
some guys today get them to shoot and some don't.
somewhere there must be a reason.
bruce.
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