I’m sorry you misunderstood my post let’s start over and I’ll clarify . first I use mason reamers and they are around 350.00 when you include go and no go gauges. That’s the purchase price ( my cost) The 1,000.00 I was talking about was for a reamer rental ,from me 60.00. the new barrel, and chamber by a gun smith .now you have a new caliber/375 . That is if you already have a 416 Barrett or a 50 call rifle. To be clear what I’m talking about is a barrel swap to another caliber that has the same base snd rim size as you existing gun .let me be very clear about this the gun that shoots my new cartridge ( 007-375 ) A -2” 50 BMG is built on an existing McMillan tack 416 retail cost 9,000.00 . To convert to 375 you need a new cartridge, a new barrel, a gun smith to chamber aprox 1,000.00 . or you could as you suggested build a hole new gun , or buy a new one 5.000-9,000 . This is not an experiment it’s done! my brass is built by RCC the gun shoots amazing . And it’s been a long time since some one called me sonney at 70 years old I do need my reading glasses . Maybe I’m not alone on that ! Part two , the new cartridge that has a cheytac rim size ( 640 ). Is in fact a new gun build for me . Stiller tack 408 1.45” action 30”-1/8” twist proof research barrel . Coustom carbin fiber stock and gun smithing by blagg rifles in penelton oregon and brass by RCC . this agin is not theoretical , it’s sitting here on my reloading bench! this cartridge has a rim size that’s compatible with the 640 size cartridges powder capacity is right between 375 Enabler and 375 cheytac 140/150 grs and agin to be very clear if you own a gun that has a bolt size of 640 for around 1,000.00 you could change change barrels , rent a reamer from me , rechamber and be shooting a new cartridge, that’s what I’ve been talking about hope I’ve cleared up any misconceptions for you thanks for for interest Mike