You did not state what case you are shooting. Lyman's reloading manual is an excellent source of information on cast bullets of all calibers and weights. Generally, you can use jacketed bullet data for cast and be safe. Pressures will be less and velocities higher - generally. You always need to work your loads up. You have to be careful about achieving high velocities with cast bullets. Depending on the cast alloy being used, if they are gas checked or not, throat condition, cylinder alignment, etc you could range any where from 1200 fps to over 2400 fps and not get leading in your barrel. Soft lead bullets should be kept under 1000 fps and most probably 800 fps to be sure you do not get leading. If you purchase your bullets, in some cases, you can get data off of their web site or you can contact them for data. You must be loading a fairly big caliber if you are using 350 grain bullets. Are you loading for a hand gun or a rifle? You really did not give us much to go on. Good Shooting to you and Good Luck.