Looking for cowboy load speed 45-70 data with IMR 4198

[burneyr]

Picked up a JM Marlin guide gun recently. I have a few hundred pieces of brass prepped and primed along with five pounds of IMR 4198 and 405gr lead bullets.

Ideally I'd like something soft in the 1200 fps range. Thought I'd start with Trapdoor equivalent load data. Has anybody here had experience with this gun / component combination?

 

[DWalt]

27 grains of 4198 will get you there. MV should be around 1300. If you want more, you can increase to 32 grains. That is what I use for a Trapdoor rifle.

Hodgdon's Cowboy Load data sheet recommends 27-31 grains 4198 behind a 405 grain cast bullet. http://www.survivorlibrary.com/library/hodgdon_2002_blackpowder_reloaders_manual.pdf

 

[rockquarry]

I think the Lyman book has loads broken down by the strength of various action types, and probably plenty of IMR4198 loads.

 

[burneyr]

DWalt thanks a million - the other loads in that pdf will come in handy too.

Before now I had never used any 4198, but looking through my manuals it seemed very efficient for the 45-70. Just set up and calibrated my electronic dispenser - this stuff meters like cordite.

The kids ought to have some fun with this over the holidays. Appreciate your help.

 

[mod29]

31-gr of IMR 4198 with a 405-gr cast bullet gives me good accuracy out of my Ruger #1. It's at the bottom of the chart in the Lyman's reloading manual for trapdoor loads, but it still packs a good punch.

 

[jeeps]

13-14 grains of Unique with hard cast 405 bullet. No filler needed Unique is not position sensitive. Very accurate!!

 

[DWalt]

When I bought my first .45-70 (a trapdoor Carbine) in the late 1960s, it came with a Lyman 310 set and a couple cans of IMR 4198. A friend was a bullet caster and made me some 500 grain bullets. I don't remember my loads, but they were light. They had to be as shooting that carbine with anything else was rough on my shoulder. I later sold it and bought an 1884 trapdoor rifle which I still have. Also have an 1895 Marlin from the mid-1970s. I never really enjoyed shooting it much and never hunted with it, but it looks cool.

 

[Kinman]

13-14 grains of Unique with hard cast 405 bullet. No filler needed Unique is not position sensitive. Very accurate!!

A friend of mine uses a load very similar to this with his Marlin Guide rifle, its his plinking round and does quite well at 50yds. Something else to consider if you are just looking for something to plink with is trying a lighter weight bullet. I have an early trapdoor that was converted to a "Gemmer" style Hawkin rifle, with a half stock and Douglas Octagon barrel. I only use black powder but that custom bullet only weighs 325gr. There is a huge difference in felt recoil between the 325-405 using the same amount of powder. I developed that load to use on a bear hunt this coming year, very accurate at 50 yards.

 

[venomballistics]

Been orbiting this thread for a while.
Essentially your looking for a cowboy action load.
You don't need a 405 grain baseball sized chuck of lead here.
Something 300 - 350 would be more than sufficient.
4198 should work out, but you have a gun that can take some pressure
I'd comb the data sources for 4227 loads. The theory being that taking advantage of the higher operating pressure can give you more consistency at a reduced velocity

 

[smoothshooter]

The Lyman Cast Bullet manual is your friend.

 

[TheTinMan]

27 grains of 4198 will get you there. MV should be around 1300. If you want more, you can increase to 32 grains. That is what I use for a Trapdoor rifle.

Hodgdon's Cowboy Load data sheet recommends 27-31 grains 4198 behind a 405 grain cast bullet. http://www.survivorlibrary.com/library/hodgdon_2002_blackpowder_reloaders_manual.pdf

Thank you! Another nice data source, and not just for .45-70.

 

[Nemo288]

I'd comb the data sources for 4227 loads. The theory being that taking advantage of the higher operating pressure can give you more consistency at a reduced velocity

IMR4198 is faster than the "H" version (ADI AR2207) and works fine for slightly reduced loads.
I have used IMR4227 with good success in the 444 for even more reduced loads.
Then 2400 for 44 mag carbine equivalents in the big brass.
The case is about half full here and I do use filler at this point.
The 45-70 and 444 use very similar reloading technique and philosophy.
Your idea of keeping the pressure up while reducing the velocity is sound and one I concur with.
Going further down the line, Unique has been used for mouse loads in just about every rifle ever made.
As mentioned the Lyman cast handbook is our bible there.

 

[steelslaver]

I fill my cases completely full of FFg black powder then use a die with a cut off de priming insert to compress it to where the base of the bullet will be when seated past front band.

Best if fired with a slight breeze from behind or to one side. Do not fire into the wind.

My 45-90 gives off 29% more smoke.

 

[venomballistics]

IMR4198 is faster than the "H" version (ADI AR2207) and works fine for slightly reduced loads.
I have used IMR4227 with good success in the 444 for even more reduced loads.
Then 2400 for 44 mag carbine equivalents in the big brass.
The case is about half full here and I do use filler at this point.
The 45-70 and 444 use very similar reloading technique and philosophy.
Your idea of keeping the pressure up while reducing the velocity is sound and one I concur with.
Going further down the line, Unique has been used for mouse loads in just about every rifle ever made.
As mentioned the Lyman cast handbook is our bible there.

I also see Red Dot in some of the legacy data.
Reducing "too far" kinda conflicts with my sensibilities. At some point, things are better served with some flavor of PCC. There's absolutely no shame in a Henry Big Boy in 44 magnum.
A sound arm to consider for this years Easter Egg hunt.
As the 45-70 goes ... I'm almost exclusively mid lever level 405 grain. It's a rifle that must be fired twice, as recoil is used to reset the shoulder dislocated by the previous shot.
If ya need some mercy, I have smaller things to hand ya

 

[Skeet 028]

I shot 30 grains(mostly H-4198) with a 405 nominal cast bullet out of my Marlin 1895 Cowboy rifle(24 inch Octagon). As someone said the 2nd shot resets the shoulder.... and it was Magnaported. The Contender was no fun with that heavy a bullet. I used a Lyman 290 gr HP bullet in the Contender. It was still a thank you Jesus load after the 5th or 6th round. IIRC I also used Reloader 7 in the 45-70

 

[venomballistics]

I shot 30 grains(mostly H-4198) with a 405 nominal cast bullet out of my Marlin 1895 Cowboy rifle(24 inch Octagon). As someone said the 2nd shot resets the shoulder.... and it was Magnaported. The Contender was no fun with that heavy a bullet. I used a Lyman 290 gr HP bullet in the Contender. It was still a thank you Jesus load after the 5th or 6th round. IIRC I also used Reloader 7 in the 45-70

After discovering that the Hornady FTX brass was short, I designated it for use with 500 grain.
In a "if you could have just one gun" debate ... one could do worse than a 45-70. There's a lot of playground in that cartridge.
I might not exploit that range of utility as I do other chamberings, but I certainly recognize it.
A coated .460 round ball, flat sided through a sizing die might be interesting over one of the legacy red dot or unique loads.

 

[Kinman]

I fill my cases completely full of FFg black powder then use a die with a cut off de priming insert to compress it to where the base of the bullet will be when seated past front band.

Best if fired with a slight breeze from behind or to one side. Do not fire into the wind.

My 45-90 gives off 29% more smoke.

I'm going to agree with Ken completely about using black powder, the recoil is much more manageable for one thing. I switched over to Swiss a few years ago for just about anything that requires accuracy. Swiss does not require the compression that Goex does, fills the case more consistently, a .030 wad is about all I have between an 75gr. load and target bullets in my Sharps 45-90. My 45-70 Gemmer rifle uses a 325gr. bullet over 70gr. 1-1/2F Swiss and a .030 wad, must use Winchester cases as they have the thinnest wall allowing maximum powder charges. The beauty of the 45-90 is finding the sweet spot between 70-90 grains of powder, mine settles down with 75 gr. 1-1/2 F Swiss and a 538gr. P. Jones bullet over a .030 wad. Couple years ago I was challenged by an old friend to shoot 2" at 200 yads, or MOA. I answered his challenge with a solid 1.75" five shot group in the 10 ring.

 

[burneyr]

Bumping this one back to the top-

I usually reply with actual data after soliciting assistance so it might help others who run into this thread later. Many thanks to those who pointed me in the right direction.

Chronograph results out of a JM Marlin 1895G 18 1/2 inch factory ported barrel. These are five shot averages all using Winchester standard large rifle primers, Starline 45-70 brass, 405gr HiTek coated T&B bullets, and IMR 4198.

Very pleased with the accuracy - ladder test produced a vertical group in my test target around 1 1/4 wide by 3 inches tall in a solid slit at 50 yards. I'm using the XS brand sights which have a very generous rear aperture. Never expected that it could deliver repeatable results given the opening size.

I fell a tad short of my desired 1200 FPS target velocity, but the accuracy was superb for this combination. Called it close enough - it's a pussycat and can be shot all afternoon without being beat to death. Smacks an 8 inch steel plate at 100 yards with boring regularity and authority.

Onto the results:

27gr IMR 4198 - 1092 FPS

28gr IMR 4198 - 1128 FPS

28.5gr IMR 4198 - 1156 FPS

29gr IMR 4198 - 1194 FPS

 

[smoothshooter]

Get a reloading manual.
Lyman Cast Bullet Manual is one of the best.

 

[Timb1]

13-14 grains of Unique with hard cast 405 bullet. No filler needed Unique is not position sensitive. Very accurate!!

I have an 86 Browning that I shoot a 340 grain cast bullets with 10 grains of unique. It is very accurate and has the recoil of a 22lr.