I am just getting started in reloading. I have a Remington model 722 in .257 Roberts. The factory bullets I have (Remington Core Lokt), have a crimping groove. A year ago I had planned to get started reloading but I have not found the time until now. I bought some powder, primers and bullets at the local gunshop. The bullets have a crimping groove. If a bullet has the crimping groove, does it have to be crimped or can it be loaded without crimping? And- how do I know if crimping is necessary, or beneficial? My rifle has a box magazine so the shells aren't stacked end to end. I have been reading the Speer reloading manual, BTW. Thanks.