I have a partial box of 60 grain WW shells. The 250 brass measures only .260" at the base. The most undersized brass I have ever seen. GD
.460" maybe?
I had the same experience! I picked up about 5 boxes of Winchester Silvertip loaded ammo several years ago. I noticed the cases sometimes fail to eject as expected, sometimes falling back into the ejection port. I Called Ruger, suspecting the rifle was out of spec. To their credit, they asked me to send it in to be checked out. Before I did, however, I measured a few Winchester cases and compared them to Remington .250 cases. Yes, the rim diameters were .460 and .473, respectively. I certainly have plenty to learn about guns/ammo/handloading and such, but this is the only time I ever have known factory cases to be that far undersized in rim diameter. I never sent the rifle to Ruger. It works perfectly well with Remington cases and had it been out of spec, I expected they would have offered to just replace it, with another in-production chambering such as .308 or .243. I like my .250-3000 and didn't want to do that. I think the .250 chambering may have been a special distributor run, and so not currently in production.
So why would Winchester do that? Or how could it have happened accidentally? From the little I do know about factory loading machines and setup, a change in case dimension is bound to cost LOTS of money, starting with production of the cases themselves, and then followiing through to the loading process.
