I’m playing around in CAD and making a 375 Whelen reamer drawing. I’ve seen several other 375 Whelen reamer prints with neck diameters ranging from .398” to .407”. I want to just use 35 Whelen brass and neck it up. When you guys spec a neck diameter, do you just use the maximum possible brass thickness of the parent cartridge as your starting point or do you bases it on how the neck will get slightly thinner as it stretches? I know I am making this too complicated, but I’d like to know how you do it. If I base it on the thickness of the parent cartridge, the maximum neck diameter of the 375 Whelen will be at .405”. If I base it off a loose calculation for getting thinner as it stretches, the neck diameter will be .4038”. This is all at the case mouth. You can probably tell that I don’t want to turn necks. I’d appreciate some insight from you guys to hopefully avoid some headaches.
