358 D&R Magnum

[Macduff]

Anyone heard of this caliber before?

I picked up a nice Ruger #1 chambered for it...but I can't find anything about it.

I'm guessing that it's a wildcat, as the only thing I can find is a single forum post quoting a post from a different forum, stating that it's a 378 WBY case necked down to .355.

Worst case, I'll get a new barrel for it, but I figured I'd see if any of yall know of the cartridge first.

IT came from the estate of a hunter in Indiana and he had used it on a hippo at one point, which was interesting.

 

[jruby]

Get a chamber cast done and then decide how to move forward. It is always good to know what you have and then make a decision. Once had a 35 weatherby was easy to neck up 300 weatherby to 35 and fireforn it. Friend has the rifle now.

 

[greyfox]

Jruby nailed it,, get a chamber cast.

Kits are (were?) available from Brownells. Wildcats are just that, and even if you have one marked as such, there are different manufacturers of reamers and the only way to know the specs are A: Cast the chamber or B: Shoot what you hope is something close or you'll not have to worry about shooting again!