Just picked up a 10rd 223 case gauge from Armanov and am really impressed with it.
They make these stackable sleeves that are 10rds each. I only have one 10rd sleeve so far, but you can couple 5 of them and transfer directly to mtm boxes if that's yours thing.
Don't recall ever seeing people mention them on here and thought I would tempt a few of you.
https://usa-shop.armanov.com/product/case-gauge-223-rem-10-rnd-stackable/Load it first with the part sitting against the table. The bullet will sit on the table by design and push the case out of the gauge. This is so you can visually inspect to see if you have some OAL seating issues.
Attached FileNow pick up the gauge and the round will fall into the gauge. Now it operates just like a case gauge, but you can test 10-infinity rounds all at once.
Attached FileHere's a video demonstration
Armanov Case gauge .223 REM Stackable
I have no affiliation with the company, they're based out of Slovenia. I'm really impressed with the device though!
They also make a 100rd version for 9mm that I picked up. Equally as impressed with it.