Mild 45-70 Load

[Crowman]

I'm working up a mild load for an ASM reproduction Sharps single-shot cavalry carbine. The Laser Cast book listed 21.0 grains of IMR 4198 as a starting point and 27.5 as a maximum for their cast 405 grain Flat Point bullets. I want to use 25.5 grains, sorta mid range load.

When I looked on my bench, I found that I have H-4198 instead. The Hodgdon's manual listed 27.0 grains H-4198 as a starting point, capping out at 31.0 grains.

My question, is 25.5 grains H-4198 too low to use under the cast 405 grain FP in the Sharps repro?

 

[SHR970]

Just looking at the Hodgdon on line data, that charge is low for either flavor of powder.

Me myself, I would bump it up to at least the 27 grain starting load. The on line data shows this as a 14,200 CUP load. That is really mild pressure wise. Going much lower and you risk a squib load.

 

[rcmodel]

Yep!

Lyman #49 says a 405 cast Trap-Door start load of IMR-4198 is 31.5 @ 12,400 CUP.
Can't imagine H-4198 would be that much different.

rc

 

[ArchAngelCD]

I'm shooting 32.0gr IMR4198 under a 405gr LFN bullet in my Trapdoor. When using H4198 you do use less powder than with the IMR version so drop the Max back by 1.0gr and the starting charge back by 2.0gr.

 

[FROGO207]

I like Trail Boss for the trapdoor loads and have had really good results in my rifle. If you decide to try a different propellant I would recommend you try this one for any lead bullet.

 

[kutter]

Wait, this is s trick question by the OP right, like what colour is a Unicorn? There is no such thing as a mild load for a 45-70, it is a mythical beast, it is like BIGFOOT!

 

[Crowman]

Once you've ran Garrett Hammerheads through a Marlin Guide Gun, then "mild" .45-70 loads take on a different meaning.

Thanks for the info, guys.

 

[jack44]

what about 13 18 grain of unique? and a 405 or 350 cast bullet thats soft and mild.

 

[Asherdan]

I wouldn't call it the 'best' soft shooting load but if it's what you have on hand following the current the Hodgdon data for H-4198 and a 405g cast certainly works and is safe for your type of rifle. I would not go as low as the Oregon Trail data suggests.

If you don't mind something new...

Accurate 5744 is really good in the 45-70 for "BP" level loads. The current manual even has data specific to 5744 and the Laser Cast bullet you're using.