My rebarreled Marlin XL7 (.270 to Shaw .338-06) shows a preference for Speer 225 gr. BTSP bullets regardless of powder or velocity. I was working on new loads with Sta-Ball powder this morning and my ‘LH’ bench shooting gave a decent 4 shot group without actually trying very hard. I normally shoot ‘RH’ but was giving that achy shoulder a break today. These or similar results have been seen with four different powders over a 200 fps velocity range. It shoots Nosler 200 gr. CT bullets nearly as well but the groups open up slightly with Nosler 180 gr. BT bullets / have not been able to get under 3” with Federal 200 gr. Fusion. At least I know which bullets to restock!