Still reading n researching. My NEF 45-70, at what Vel. do you need to use a GC ? I plan on staying in the nice recoil area of Trapdoor loads but using smokeless. My tick toter hunting range is 100 yds n less. I don't think i can see 75 yds on my place once the leaves fall. I have Meister 350gr cast boolits to load, they are .458. I am going to start with 4759 powder at 22gr.