Cummins Industrial Mini Mill info please

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Yeah, mostly 80% lowers (10 and 15 type) and DOM tubing receivers. Want to make a receiver that I can switch barrels on easily using a Savage bolt for the interchangeable bolt head. I'm thinking of having a free floating barrel with a piece of DOM that threads over the receiver and holds down a lever that clicks into the barrel similar to a M2HB BMG set up. I will have to use a go-gauge every time I change barrels to set headspace but I shouldn't need to torque it together or anything.