elkholic i sure do like the sherman case , it looks good. I have a 338/06 AI and it likes reloader -15 powder. I think I get 2800 with the 215 so your sherman out shoot it at least 50 fps and you are in the same energy as the 338 win. I have a 375 Brown Whelen that Harry Mcgowen did for me after a conference with P O ackley son in law 30 years ago and it will really = the H&H factory loads and I think your sherman will do the same with a better neck to seat the bullet. it likes Reloader 15 also. and I am sure both will like R-16 just as well.