I plan on trying to shoot cast bullets to see what it is like. I would appreciated any direction to help me acquire the information I need to prepare my rifle for this. I will be shooting .308 caliber in a heavy barrelled Ruger M77. I guess the first step is to slug the barrel to know the exact groove diameter? Where are instructions on how to do this correctly. Do I need to get the bore perfectly free on any copper first? I thank you all for any help in getting me started. I am brand new to this forum. I did alot of shooting in the southern Arizona desert-good rifle country. I now live on a farm in northwest Ohio. The fields are small, the distances are shorter, so I still want to shoot .308, but slower and quieter.