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Got a box of 20 45/70 Cowboy Load RNFT 405 gr cartridges by Grizzly. Any idea of the C.U.P./psi these generate? Are they safe in a Pedersoli Sharps? Or only for a modern barrel (eg Marlin 1895)?
45/70 Cowboy
- Thread starter Blackrock
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Cowboy loads will be fine in your Sharp's style rifle. Most 45/70 ammo is marked on the box as to the safe use in all guns or modern only.
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Cowboy loads dont always mean low pressure...Many are not but i would imagine its fine in a Pedersoli. They proof test ever single barrel.
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Which Cowboy loads are not low velocity/pressure? They are supposed to duplicate the old BP loads for the CB shooting events.
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No, they are supposed to duplicate the velocity and typically they are safe in any modern rifle. Just look at Trail Boss load data and compare the peak pressure to a black powder load.
A max load of Trail Boss makes over 25kpsi with a 405gr bullet at around 1000fps. So dont confuse "Cowboy" load ammo with low pressure like black powder. BPCR loads and Cowboy loads can be worlds apart in pressure.
https://hodgdon.com/trail-boss/
A 45/70 load of Blackhorn209 using the same weight bullet at 1200fps does not even break 18kpsi.
A max load of Trail Boss makes over 25kpsi with a 405gr bullet at around 1000fps. So dont confuse "Cowboy" load ammo with low pressure like black powder. BPCR loads and Cowboy loads can be worlds apart in pressure.
https://hodgdon.com/trail-boss/
A 45/70 load of Blackhorn209 using the same weight bullet at 1200fps does not even break 18kpsi.
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Factory Cowboy loads are safe in any 45/70 rifle. The manuf's load them below the pressure limits of the old rifles, with trapdoors being the weakest design. Hodgdon load data for trapdoors goes as high as 27,000psi. What do you consider the pressure limit for a trapdoor rifle?
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The box gives a velocity of 1000 fps. It states only use in modern barrels. So does a Pedersoli repro constitute a "modern barrel"?
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You may safely shoot them. Yours is a modern barrel. Damascus barrels are the ones to only use BP loads in.
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Hoping to hear that. Thanks!!
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Ok... I guess I am not worried about the barrel but the falling block apparatus. Grizzly Cartridge a disappointment. I have called twice and emailed about C.U.P. value but no response. The gal that answers the phone pleasant and remembered me when I called the second time. However, she said she does not have C.U.P. values -- only the owner does and she will give him the message to call me -- again. That was 5 days ago and no call nor response of any kind. Can't say I recommend Grizzly Ammo at present.....
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Falling block actions are not a problem, if anything, strongest action design ever!
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Working on acquiring components to load with BP. Have new cases, Swiss BP in 2F & 3F, drop tube, lubed bullets from Montana Bullets(Great outfit), and finally obtained some Federal Magnum Large rifle primers. So far only have a Lee Classic loader. So pretty much ready to begin. Much of my reading says to enlarge the flash hole to .096 with a #41 drill bit or a 3/32 drill bit. If I do this am concerned the bit will grab the side of existing flash hole. Do most of you enlarge the hole and if so, hold in hand and be careful or another method? Do I really need to enlarge? Also, getting "Do it" and "Don't do it" recommendations regards annealing the brass --even tho straight supposedly softens and they last longer. Cost of things definitely an issue for me being retired and all the inflation of late.
My motto in old age is, "When in doubt, don't." I wish I had thought of this prior to walking down the aisle, but that issue has been resolved.
To drill the primer pocket, drill a piece of wood to accept the brass, split through the hole, insert brass and clamp in a vise just tight enough to keep the brass from spinning. Using powdered sugar to stop spinning is better than over tightening the vise.
To drill the primer pocket, drill a piece of wood to accept the brass, split through the hole, insert brass and clamp in a vise just tight enough to keep the brass from spinning. Using powdered sugar to stop spinning is better than over tightening the vise.
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You absolutely DO NOT need to drill the flash holes...........ever.
Annealing case mouths is a good thing.
Compression die is optional.
Yup. You need .030 or .060 wads. poly or fiber.........your choice.
You need a set of calipers to measure case length after you resize cases.
I use a lee case trimmer to trim cases. 45-70 cases should be trimmed to 2.095
A lee or rcbs inside/outside case chamfering tool is good to use after you trim cases.
Don't forget that you need to clean the cases after firing. X
Drilling primer pockets for real black powder used to be a standard. I have no idea what the protocol is now.
There should be a ton of info available with the popularity of BPRC matches. If I was you, I would also look into using Super Grex rather than wads. Super Grex is the filler Winchester uses to buffer shot in shotgun cartridges. I have used it quite a bit in smokeless 45/70 loads.
Super Grex can be dipper loaded on top of the powder to a level that compresses when the bullet is inserted. It works surprisingly well. It will not move and mix with the powder, it holds the powder in place, and dipper loading is plenty accurate as it weighs practically nothing.
There should be a ton of info available with the popularity of BPRC matches. If I was you, I would also look into using Super Grex rather than wads. Super Grex is the filler Winchester uses to buffer shot in shotgun cartridges. I have used it quite a bit in smokeless 45/70 loads.
Super Grex can be dipper loaded on top of the powder to a level that compresses when the bullet is inserted. It works surprisingly well. It will not move and mix with the powder, it holds the powder in place, and dipper loading is plenty accurate as it weighs practically nothing.
Right you are on that point. It does not change the fact that some people did and may still drill primer pockets for black powder. I am asserting nothing as to it being right or wrong. If you are so sure it is wrong, why don't you climb down off your high horse and provide documentation proving your point. As it is, all you are doing is insisting we bow down to your, in your mind, wisdom.
