I have Model 1873 Springield Trapdoor in .45-70 that I have been reloading for for several years. I took a break from handloading for a few years and when I recently set up my equipment I found some ammo I loaded at a documented 32.0 grains of IMR 4198 with a RCBS 405 gr. gas check bullet. I NEVER use loads outside of what I find in a reloading manual but I cannot find this load in any of the manuals I have unearthered from my collection thus far. Can anyone direct me to a site where I can find this load and determine its safety before I fire these cartridges? Thanks.

Here is the info from the Hodgdon Website:
300 GR. CAST LFP 300 H4198 .458" 2.465" 30.0 1390 14,400 CUP 35.5 1641 16,100 CUP


300 GR. SIE HP 300 H4198 .458" 2.525" 45.0 1807 16,700 CUP 55.0 2221 27,600 CUP


385 GR. CAST LFP 385 H4198 .458" 2.505" 28.0 1302 13,300 CUP 32.0 1483 14,700 CUP


405 GR. CAST LFP 405 H4198 .458" 2.540" 27.0 1251 14,200 CUP 31.0 1459 17,100 CUP


485 GR. CAST LFP 485 H4198 .458" 2.540" 28.0 1279 16,400 CUP 32.0 1434 20,400 CUP


According to them you are 1 grain over max. It is entirely possible that 32 grains may have been listed in an older manual. If this is an original trapdoor made in the 1800s I would be hesitant to shoot them but in a newer replica with modern steel it should be fine.

You can find the Hodgdon site here http://data.hodgdon.com/main_menu.asp it is free to use and is updated frequently.

There are a lot of loads listed for .45/70 Trapdoor rifles. Take care...
Oberndorf





http://data.hodgdon.com/cartridge_load.asp