45-70 Reloading Data Manual Inconsistencies

[Texasgrillchef]

Looking at the following data manuals for the 45-70 caliber from the following reloading manuals. All are the latest newest versions/editions.
Hornady, Western Powders, Lyman.

Each of the manuals will list at least 3 different categories for the 45-70.
Springfield Trapdoor, Marlin 1895, and Ruger #1. Along with the various pressure maximums for each category.

Lyman’s trapdoor data is maxed at 18k, marlin 1895 at 28k, and Ruger #1 at 40k

Hornady’s, is 25k for trapdoor, 40k for Marlin 1895, and 50k for Ruger #1.

Western’s data is 19k, 28k, and 40k.

Lyman, and Hornady, both state those limits as CUP, while Western quotes as PSI. I understand there maybe a difference in those two terms, as well a possible difference in equivalency. Yet even if you consider them on the same scale or different. Their seems to be some logic missing.

I have Marlin 1895SBL in 45-70 which I have verified with Marlin is capable of handling a steady diet of 40k rounds with no issue. That doesn’t mean I will use 40k rounds, just like I don’t drive 250mph even though my Shelby Mustang is capable of doing that speed.

What is interesting to note, is that two manuals have listed close to 18-19k for trap door, but Hornady jumps up to 25k. If this wasn’t safe for Hornady to publish, for liability reasons, I’m sure they wouldn’t publish such data.

Same goes with the Marlin 1895 data, with 2 giving 28k pressures (one CUP, the other PSi), and the third giving 40k in CUP.

For Ruger #1, you have one listing 40k CUP, the other listing 50k cup, followed by 40k psi.

While 50k and everything less is perfectly fine for a Ruger #1. The problem of safety and misreading data comes into play with the Marlin 1895, and the Springfield Trapdoor.

You wouldn’t want to put a 40k load in a Marlin that could only handle 28k. Likewise, if your Trapdoor can only handle 18k or 19k you wouldn’t want to put a 25k load in it either.

Which now has me wondering about commercial loads. You can go to almost any major retailer of ammunition and buy OTC cowboy loads for being safe in your trapdoor, and stronger loads safe in your Marlin. Through speciality outlets, or special order you can even get heavy and hot loads rated in the 40k and 50k areas. Where depending on the ammunition they clearly state not safe for trapdoors, safe for Marlins and Rutgers, or not safe for Marlins and Trapdoors and only safe in Ruger #1’s.

That’s just the start of the inconsistencies, now fo look at the data and compare for even the same powders and same bullets across all three manuals, across all three rifle types. (9 options total) and while the basic grain range will be in the same proximity. The lower minimums and upper maximums, for a given pressure, bullet and powder will vary from 1/2 grain to as much as 2 grains difference.

Yes, obviously the gun, the primer, and the case they used varies between the three manuals, and yes 1/2 grain difference in a 45-70 load may not make that much difference in relation to the total volume, as well as powder used. But 2 grains could. Which is obviously the reason one works up a load until they get the results that they want, or the maximum is reached. Also this makes a good reason to chronograph your results and compare them to results of commercial ammo that you yourself chrongraphed as well.

Now for my Marlin 1895, I know I am pretty much safe with working with the data for all three that state 40k loads, and not from the singular Hornady 50k data.

When I compared same bullet, with same powder at 40k with all three manuals. They were all in the same range. Except for the minimum and maximum data being off by about 1 grain + or -.

I have had my rifle a while and while I have been reloading for a little over a year now, I am just now getting into reloading the 45-70. As now I have collected enough brass worth reloading. I have been only reloading 380, 9mm, 45acp, and 45 colt until now. I will be loading light and hot loads in 300, 400 grain bullets.

Anyone else out there with a Marlin 1895 class 45-70 rifle and reloading?

Did you start off with using any of these manuals? If so which one? What are your top 3 powders of choice?

I am starting out testing with the following 4 powders. Accurate 5744 & 2130, IMR4198, and Reloader 7

 

[Jim Watson]

SAAMI maximum for .45-70 is 28,000 whether CUP or ppsi. They make no allowance for 19th century or 21st century guns.
I think the Lyman top "Trapdoor" load at 18000 is about right. The original Accurate Arms manual arrived at a standard by firing full charge black powder loads in their pressure gun and got about 20000 in various BPCR calibers, so they decreed that the maximum with smokeless.
A Pedersoli replica Trapdoor of "modern" materials is CIP proof tested for use at 28000 and will probably stand up to it ok.

When the new 1895 Marlins came out in the 1970s, they were advertised as "suitable for 1886 Winchester loads" and with "conventional rifling for cast or jacketed bullets." Times have changed and I am sure they will now tell you to stick to SAAMI. But there are heavier "lever action" loads all over the place.

 

[ericuda]

1895 gg. 5744, imr3031 and trailboss. My shoulder limits me more than the gun. I limit it to 1500 fps which is plenty for anything I need.

 

[Texasgrillchef]

SAAMI maximum for .45-70 is 28,000 whether CUP or ppsi. They make no allowance for 19th century or 21st century guns.
I think the Lyman top "Trapdoor" load at 18000 is about right. The original Accurate Arms manual arrived at a standard by firing full charge black powder loads in their pressure gun and got about 20000 in various BPCR calibers, so they decreed that the maximum with smokeless.
A Pedersoli replica Trapdoor of "modern" materials is CIP proof tested for use at 28000 and will probably stand up to it ok.

When the new 1895 Marlins came out in the 1970s, they were advertised as "suitable for 1886 Winchester loads" and with "conventional rifling for cast or jacketed bullets." Times have changed and I am sure they will now tell you to stick to SAAMI. But there are heavier "lever action" loads all over the place.

Which for me raises several questions.

Obviously a large number of shooters are loading 45-70 in these hotter loads of 28k, 40k and 50k, as well as buying commercial ammunition in these levels. So much so that not just one but at least 4 different companies release the data for loading at these levels, as well as companies having enough demand to cause several to sell this ammo. The Vihtavuori reloading guide, ONLY lists the load for the Ruger #1. They don’t say if it’s a 40k load or a 50k load.

Many are safely doing so, or I don’t believe it would be published at those levels by at least 4 companies, and ammunition sold by at least 3 that I can find.

So one of my questions that I am wondering is why doesn’t SAAMI release standards for these new modern rifles?

When 45acp and 9mm were first introduced the +P moniker was unknown. Now you find +P of both these calibers as well as the data to be quite common place. It’s also common place to see it stamped on the brass by many different companies.

So why is it we don’t have a +P and a ++P designation for 45-70 as well? Seems like 45 colt has a similar issue as there are standard 14k loading data and High pressure 30k loading date available, as well as commercial 30k 45 colt as well.

Is there a reason why SAAMI doesn’t want to standardize the 45-70 and 45 colt higher pressures?

I assume this is also the reason why those companies that make the Brass also don’t want to release brass with the +P and ++P monikers stamped on the brass as well?

 

[Fyrstyk]

Looking at the following data manuals for the 45-70 caliber from the following reloading manuals. All are the latest newest versions/editions.
Hornady, Western Powders, Lyman.

Each of the manuals will list at least 3 different categories for the 45-70.
Springfield Trapdoor, Marlin 1895, and Ruger #1. Along with the various pressure maximums for each category.

Lyman’s trapdoor data is maxed at 18k, marlin 1895 at 28k, and Ruger #1 at 40k

Hornady’s, is 25k for trapdoor, 40k for Marlin 1895, and 50k for Ruger #1.

Western’s data is 19k, 28k, and 40k.

Lyman, and Hornady, both state those limits as CUP, while Western quotes as PSI. I understand there maybe a difference in those two terms, as well a possible difference in equivalency. Yet even if you consider them on the same scale or different. Their seems to be some logic missing.

I have Marlin 1895SBL in 45-70 which I have verified with Marlin is capable of handling a steady diet of 40k rounds with no issue. That doesn’t mean I will use 40k rounds, just like I don’t drive 250mph even though my Shelby Mustang is capable of doing that speed.

What is interesting to note, is that two manuals have listed close to 18-19k for trap door, but Hornady jumps up to 25k. If this wasn’t safe for Hornady to publish, for liability reasons, I’m sure they wouldn’t publish such data.

Same goes with the Marlin 1895 data, with 2 giving 28k pressures (one CUP, the other PSi), and the third giving 40k in CUP.

For Ruger #1, you have one listing 40k CUP, the other listing 50k cup, followed by 40k psi.

While 50k and everything less is perfectly fine for a Ruger #1. The problem of safety and misreading data comes into play with the Marlin 1895, and the Springfield Trapdoor.

You wouldn’t want to put a 40k load in a Marlin that could only handle 28k. Likewise, if your Trapdoor can only handle 18k or 19k you wouldn’t want to put a 25k load in it either.

Which now has me wondering about commercial loads. You can go to almost any major retailer of ammunition and buy OTC cowboy loads for being safe in your trapdoor, and stronger loads safe in your Marlin. Through speciality outlets, or special order you can even get heavy and hot loads rated in the 40k and 50k areas. Where depending on the ammunition they clearly state not safe for trapdoors, safe for Marlins and Rutgers, or not safe for Marlins and Trapdoors and only safe in Ruger #1’s.

That’s just the start of the inconsistencies, now fo look at the data and compare for even the same powders and same bullets across all three manuals, across all three rifle types. (9 options total) and while the basic grain range will be in the same proximity. The lower minimums and upper maximums, for a given pressure, bullet and powder will vary from 1/2 grain to as much as 2 grains difference.

Yes, obviously the gun, the primer, and the case they used varies between the three manuals, and yes 1/2 grain difference in a 45-70 load may not make that much difference in relation to the total volume, as well as powder used. But 2 grains could. Which is obviously the reason one works up a load until they get the results that they want, or the maximum is reached. Also this makes a good reason to chronograph your results and compare them to results of commercial ammo that you yourself chrongraphed as well.

Now for my Marlin 1895, I know I am pretty much safe with working with the data for all three that state 40k loads, and not from the singular Hornady 50k data.

When I compared same bullet, with same powder at 40k with all three manuals. They were all in the same range. Except for the minimum and maximum data being off by about 1 grain + or -.

I have had my rifle a while and while I have been reloading for a little over a year now, I am just now getting into reloading the 45-70. As now I have collected enough brass worth reloading. I have been only reloading 380, 9mm, 45acp, and 45 colt until now. I will be loading light and hot loads in 300, 400 grain bullets.

Anyone else out there with a Marlin 1895 class 45-70 rifle and reloading?

Did you start off with using any of these manuals? If so which one? What are your top 3 powders of choice?

I am starting out testing with the following 4 powders. Accurate 5744 & 2130, IMR4198, and Reloader 7

IMR 4198 has been my go to powder for my Ruger#1 in 45-70.

 

[Texasgrillchef]

IMR 4198 has been my go to powder for my Ruger#1 in 45-70.

Which manual did you start off using to reference first?

Have you had any issues finding any imr 4198? i havent been able to find any. Other then 8lb bottles. wanted to start off trying 1pb worth before going to that amount.

 

[Blue68f100]

Where all using the same bullet?
Same OAL?

A difference in these can greatly impact the load.

 

[Texasgrillchef]

Where all using the same bullet?
Same OAL?

A difference in these can greatly impact the load.

Yes, compared the same bullet, and they had same OAL as well.

 

[Sistema1927]

The nice thing about .45-70 is that you can duplicate the 19th century load performance, and still take any critter in North America cleanly. While you can hot rod it up considerably in modern guns, you really don't gain much, possibly a little flatter trajectory, but with increased recoil and stress on the gun.

 

[AJC1]

I shoot trail boss loads and very moderate 3031 loads. My marlin lever gun han handle more than I can by a lot. I shot a few of the lever revolution rounds was done.

Why is there different data, because each company has different lawyers and came to the final risk assessment a little differently. I dont believe you will find a load in a current manual that would be dangerous in a well maintained good condition weapon.

 

[mrawesome22-250]

The 450Marlin was the answer to all this confusion.

 

[Trashyshoots]

Take this with an industrial size grain of salt, since I do not reload yet, but have read basically everything I can on the subject. But I would be inclined to use varget for 4570 loads. Varget seems to have a much lower pressure than other powders in 4570s. Infact I bought varget for 4570 loads and it seems like it will be good in 223 loads for my contender as well.

 

[lordpaxman]

I’m following this because I recently obtained a Henry .45-70 and will be reloading soon. Henry doesn’t recommend reloads, but I plan to load trapdoor and Marlin equivalents. My shoulder doesn’t need the upper end loads.

 

[40-82]

Take this with an industrial size grain of salt, since I do not reload yet, but have read basically everything I can on the subject. But I would be inclined to use varget for 4570 loads. Varget seems to have a much lower pressure than other powders in 4570s. Infact I bought varget for 4570 loads and it seems like it will be good in 223 loads for my contender as well.

Actually, you've hit on something quite good. I've used Varget behind my 325 grain RCBS cast bullet to reach 1800 fps, a trapdoor level load. Twice, this load has killed two deer in one shot. It would have been more economical still, had the bullet lodged in the second deer, and I could have recovered it, and melted it down, and used it again, but that didn't happen.

The good thing about the 45-70 using cast is that you can eat right up to the hole. It makes a wonderful wild turkey cartridge.

You won't recover many cast bullets from game out of the 45-70 unless you shoot something bigger than a whitetail.

 

[Trashyshoots]

Thats excellent news.

 

[Fyrstyk]

Which manual did you start off using to reference first?

Have you had any issues finding any imr 4198? i havent been able to find any. Other then 8lb bottles. wanted to start off trying 1pb worth before going to that amount.

My load is from the Hornaday manual (Don't know the year) for a 300 grain bullet using 50 grains of IMR 4198. This load is not a maximum load, but it gives me 1.5" groups at 100 yards. Its all I need for deer. It drops them on the spot usually. I have a good supply of IMR 4198 as I bought 2 8# cans several years ago when a gun shop was going out of business. I use the powder in the 45-70, .222, 30-30, and .375.

 

[Jim Watson]

So one of my questions that I am wondering is why doesn’t SAAMI release standards for these new modern rifles?

Because nobody has asked them to.
SAAMI is not a marketing organization or a consumer representative, they are a standards organizer akin to ASTM.
If some MEMBER ammunition company wanted to standardize .45-70 +P, there is a rigamarole to go through,
Example:
SAAMI Registration
The .277 SIG Fury was filed with SAAMI in summer 2019 and the registration is expected to be completed early in the first quarter of 2020.

 

[badkarmamib]

When my father bought his Henry lever action in .45-70 and asked me to help him with reloading, I found the same problem. Dad really liked the Sierra 300gr JHP, and I like Hodgdon powder. I went to Hodgdon's site, where I found IMR4198 data for trapdoor loads was higher than Lyman lever loads (or something like that). After much contemplating, we followed Hodgdon's data, as they used the exact bullet and powder. To be safe, we only loaded 5 rounds at the 45 grain starting load, which, again, was the starting load for trapdoor from Hodgdon, but a high lever load from other sources. He fired those 5, liked the group, 2,000FPS was plenty for whitetail, and, on a later trip when I tried it, we decided it was plenty of recoil, as well. He has since run a couple of hundred of this load through the rifle, and is still pleased. The one problem, partially unrelated, that I will caution you to watch for, is crimp. 45-70 needs a good crimp to burn properly, otherwise the primer flash could push the bullet into the lands, before fully igniting the powder, leading to much frustration.

 

[SlowFuse]

I’m following this because I recently obtained a Henry .45-70 and will be reloading soon. Henry doesn’t recommend reloads, but I plan to load trapdoor and Marlin equivalents. My shoulder doesn’t need the upper end loads.

Sounds like a good plan! Your Henry probably doesn't need the upper end/modern rifle loads either for too long. Same logic as shooting +P out of an auto pistol constantly, the Henry can handle it but I find the 2000+ fps loads unnecessary. I haven't heard any reports on the strength of Henry's newer single shot rifles, but assume you have the lever..

After you experiment in the Trapdoor and lever range i'll bet you find the trapdoor loads are just fine for general use and lever loads are enough when you want a little more push. Trapdoor is the range I use most often, a 405 grain piece of lead going 1500-1600 fps still packs quite a punch. Jacketed lever loads going over 1800 get uncomfortable for me after a while, especially out of the lighter 1895 guide rifle.