I just started my foray into casting and powder coating my bullets. My .38 cal 158g SWC came out really well. I have an Arsenal mold - highly recommend them, very well built. I used Eastwood Ford blue powder coating, shook in a #5 container with plastic beads then 20 minutes at 400 degrees in the toaster oven. Now I want to venture out into the realm of rifle bullets for my Marlin 30-30 model 336. I’m looking at the 170g Ranch Dog clone that Arsenal makes. I have a choice of gas check or no gas check. If I powder coat these bullets do I still need a gas check on them? Marlin people are recommending a .311 diameter bullet for the micro groove rifling which is what the Arsenal mold produces. Thanks