Don't know how much difference there is between feed rails on a factory long action magnum and say an 06 based receiver but the feed rails on a short action for 223 is narrower than feed rails on a factory 243/308. I know because I used a 223 based receiver for a while barreled to 6x47 Lapua. Cartridges would bind up about 1/2 the time. This even after I removed a bit and polished them up. Finally got a 243/308 based receiver and screwed barrel on it. Feeds 100% now. Used the first 223 receiver for a 223AI and with the bit I removed off rails and being polished it works much better now. Used to have a pic with the 2 recievers side by side but photobucket now has it for ransom.
