I carried my 45-70 SBL in Alaska last spring for protection. I was carrying BB loads +P. But since that time I have become a fan of HSM and their 45-70 405 grain "Cowboy" load. This a 15BH (?) hard cast, no gas check and it shoots wonderful and clocks about 1300 fps from my Marlin SBL 18.5 barrel. Kills deer, hogs and steel gongs with authority and is accurate and mild shooting.
But their 430 grain "Bear Load" is a true thumper with a very hard cast bullet that has a huge metplat. And herein lies the problem, they load them over length at 2.555 which is slightly over maximum length of 2.550. This over length coupled with the huge cylindrical shaped bullet and huge flat metplat will sometimes have the bullet catch on the ramp into the chamber. The ramp in a Marlin is not smooth but has a few little ridges (every Marlin 45-70 I have ever seen is this way) as the parts come together and the over long cartridge and fat bullet do not like to make the turn into the chamber and will try to jam.
If I cycle the lever smartly they feed fine but with my rifle ALL OTHER ammo, factory, home loads of all sorts and bullets, feed reliably but none are over length.
I would like to understand the HSM load, so I can duplicate it with another bullet of more favorable dimensions. I have taken a leather strops and worked the edge from the HSM and this helps feeding but it does not address the over length condition.
Does anyone have a suggestion for a suitable 420/430 grain hard cast with gas check? And I would love to know what powder and load folks use for such rounds, intended for use against big, toothy and dangerous critters.
3C
But their 430 grain "Bear Load" is a true thumper with a very hard cast bullet that has a huge metplat. And herein lies the problem, they load them over length at 2.555 which is slightly over maximum length of 2.550. This over length coupled with the huge cylindrical shaped bullet and huge flat metplat will sometimes have the bullet catch on the ramp into the chamber. The ramp in a Marlin is not smooth but has a few little ridges (every Marlin 45-70 I have ever seen is this way) as the parts come together and the over long cartridge and fat bullet do not like to make the turn into the chamber and will try to jam.
If I cycle the lever smartly they feed fine but with my rifle ALL OTHER ammo, factory, home loads of all sorts and bullets, feed reliably but none are over length.
I would like to understand the HSM load, so I can duplicate it with another bullet of more favorable dimensions. I have taken a leather strops and worked the edge from the HSM and this helps feeding but it does not address the over length condition.
Does anyone have a suggestion for a suitable 420/430 grain hard cast with gas check? And I would love to know what powder and load folks use for such rounds, intended for use against big, toothy and dangerous critters.
3C