45-70 Black Powder Loads

[ADIDAS69]

I ordered up a PEDERSOLI 45-70 trapdoor rifle, yes because of a Garand Thumb video. PEDERSOLI Recommends black powder load with bullets of 300 grains or less. Does anyone have or know where to find load data?

[105kw]

I bought my Pedersoli Trapdoor 20yrs ago. They weren't saying BP only then.
I shot trapdoor level loads through it for about 5yrs before I sold it to a coworker.
Last I heard he and his son had taken a couple of deer with it.
Look for Mike Venturinos book on Single Shot Rifles, has a lot of BP load data.

[Jim Watson]

Pedersoli Recommends black powder load with bullets of 300 grains or less. Does anyone have or know where to find load data?

Absurd
The original 1873 load was .45-70-405, the 1881 load was .45-70-500
I would not expect good shooting with bullets "300 grains and less."

https://www.amazon.com/Loading-cartr.../dp/157579019X

https://www.amazon.com/Shooting-Buff...s%2C244&sr=8-2

[ADIDAS69]

Dear Mr. Hetrick,

You can use smokeless cartridges, light type, not exceeding 18000 P.S.I.
Our Springfield Trapdoor rifles .45-70 caliber go through the same forced proof test of the much stronger Sharps and Rolling Block rifles actions.(By law we have to proof test all the guns in Italy).
It is true that our TD rifle is manufactured with improvements which are possible only with now- days technologies, however it comes from an original design which mechanic presented some weakness in the old days.
Therefore the suggestion is to use reloaded cartridge with black powder that do not exceed the 18.000 PSI (1,241 bar) or to load commercial smokeless powder cartridge, light type with bullets within the 300 grains.

Best regards,
Customer service

DAVIDE PEDERSOLI SRL
Via Artigiani, 57
I-25063 GARDONE VALTROMPIA
(Brescia) Italy
ph. +39 030 8915000
fax +39 030 8911019

[ghbucky]

FWIW, unless there is a typo somewhere in there, your original statement about "black powder load with bullets of 300 grains or less" is not what Pedersoli is saying.

The response you pasted is "load commercial smokeless powder cartridge, light type with bullets within the 300 grains"

Exactly what powder to use and how much is something you need to research into.

I don't much about loading black powder, but how are you supposed to know if a black powder/ bullet combo is under 18000 PSI?

[Scorch]

I don't much about loading black powder, but how are you supposed to know if a black powder/ bullet combo is under 18000 PSI?

Not a problem with black powder, it is not a progressive burning powder. As pressure rises, BP burn rate slows down. It's pretty hard to get a BP load above 20,000 psi unless your barrel is plugged.

A lot of people use smokelss to achieve "black powder equivalent" loads, but they really are not BP equivalent because of the burn rate of smokeless powder. At best, they are low-pressure loads that fall in the maximum pressure range of real BP loads. The pressure curves will be very different.

Loading BP replacements like Pyrodex or 777 will get you close, but fouling will cut your shooting short. I loaded American Pioneer powder in BPRC for several years, I like it and fouling is non-existant.

[mehavey]

Read & heed:
https://www.buffalobore.com/index.ph...f%20the%20ammo.

Then go to https://www.hodgdonreloading.com/rel...c=true&type=54 (45-70 TRAPDOOR)
for multiple weights (all the way up to 535gr) and stay within 20,000psi or so.

Lottsa options....

[ligonierbill]

Maybe I missed it, but it seems everyone is assuming the OP knows how to load holy black. ADIDAS69, if it is actual black powder, you simply fill the case to the point that the bullet will compress the load slightly. Do not leave air space. With a 405 or 500 grain cast bullet, this is still a formidable load. Black powder substitutes can be used, like the American Pioneer Scorch mentioned. I often use Alliant Black MZ, no longer sold, but I have found I need to use 15-20% less than I would FFg black to get the same velocity.

Today, many load modern jacketed bullets, and Pedersoli is recommending you limit your ammo to 300 gr. Heavier 0.458 bullets are available, of course. Most load manuals and data bases include appropriate loads. How do you know you are under 18,000? You don't. You are depending on the manufacturers' tests. Keep it between the lines, and you'll be fine.

[mehavey]

Again, see Post #7

[Unclenick]

Interestingly, Hodgdon's 405-grain bullet Trapdoor loads have some pressures just the same as their levergun loads. I would ask them if that isn't an oversight. I've always heard numbers like 21,000-22,000 psi max for original trapdoors, and 18,000 psi would certainly help keep fatigue down.

Pedersoli's statement that their guns, which will be made with stronger modern steels, pass the same proof as any other 45-70s. The CIP rates the 45-70 cartridge at about 32,000 psi and the proof mean value at almost 40,000 psi. Their instrumentation system is a bit different than SAAMI's, but their mean proof pressure is about the same (39,500 psi is the SAAMI mean proof value and 39,885 the conversion from 2750 bar, which is the CIP mean proof value). Nonetheless, if Pedersoli says to keep jacketed bullets down to 300 grains, that is likely because heavier weights, with their greater inertia, combine with the jackets to provide higher start pressures, and that may well put more wear and tear on the design so that I would stay with that weight number for jacketed bullets. Lead, it appears, can be shot with any safe pressure load up to the 500-grain weight without a problem.

Black powder is fun to shoot but is a cleaning chore.

[Savvy_Jack]

During 1878, the following results were achieved




Two smokeless powders used today from Lyman's 49th is 4198 and Reloder 7, used with the 405gr lead bullet.

4198/35gr/1,463fps/17,700cup
Reloder 7/39gr/1,578fps/17,900cup

[Savvy_Jack]

From the 1874

DESCRIPTION AND Rules for the Management OF THE SPRINGFIELD RIFLE CARBINE AND ARMY REVOLVERS CALIBRE 45

https://books.google.com/books/conte...9%2C653&edge=0

[std7mag]

I'm gonna go out on a limb, and say 70gr.....

Hence the 70 part of the 45-70.

[mikejonestkd]

Modern Brass has slightly less capacity that original 45-70 brass.
I typically use 66 grains in my 45-70 loads - its just enough to get compressed when i seat the bullet

[Jim Watson]

The usual recommendation for factory loads in a trapdoor is the 405 gr bullet.
Contrary to Pedersoli's notions, the usual American idea is that the 300 gr is usually loaded for as much velocity as can be done and is likely to crowd the maximum.

[Road_Clam]

If you want to correctly learn all there is to know about loading for the 45-70 and separate from all the internet BS get "the" book from J.S. Wolf :

https://the4570book.com/

[pbcaster45]

Here's a black powder load I use in my 1874 Sharps Hartford Model.

Bullet: Paul Jones 540 gr. Creedmoor (.459/20-1/SPG)
Powder: Swiss 1.5Fg 60.0 grs. (0.30 Walters Vegetable Wad)
Primer: Remington 2 ½
Case: Winchester
Comments: No compression