OK. I know this isn't a 1000 yd. cartridge. But, I have a question that is way out of my league. Currently awaiting my new .20 Practical with a no-turn .233 neck. It's the only reamer PAC-NOR has. I sized my .223 Lapua brass as follows: .223 FL die, bushing die with .233 and then finished with a .225 bushing,( process used to turn .223 brass to .20 caliber). So, I loaded a dummy round using a 40 gr Berger and it measured .227-.228 at the neck. I believe I read somewhere that it's recommended to have at least .002 clearance in the chamber. So, am I right that my loaded round should measure around .231?? REM 700 SA and Lapua unturned cases. Or do I have to actually fire a round and then bushing size the case with a bushing that will get me closer to the chamber .233 neck? Hope I made some kind of sense.