I may have bought before I thought.Purchased an original J.E.Gebby mauser in his "22 Varminter". Super custom,but I need to know if this will handle 22-250 ammo??? Rifle will properly cycle loaded shells but have yet to fire one.Any info will be appreciated. Mark

As far as I know the 22-250 is simply the commercial version. I "thought" they interchange.

The .22 Varminter is another name for the .22-250 Remington before it was standardized by Remington.

I suggest though that you do a chamber cast or have your gunsmith cast the chamber for you just to be certain that your chamber is the proper dimensions.

You can also remove the extractor and use a Go, No-GO gauge to check the headspace.

Will it "handle" .22-250 ammunition? Well, the action is certainly more than adequate for SAAMI .22-250 pressures. Whether the chamber fits is another question since old-time wildcatters did not have SAAMI specs to rely on and cut their reamers to whatever dimensions suited them. However, if factory ammunition chambers it is highly unlikely that the headspace would be excessive enough (particularly with the Mauser claw extractor to hold the case against the bolt face) to create any significant danger of a case head separation on the first firing. After that you can determine from the dimensions of the fired case whether the headspace is tolerable with factory loads.

I used a 22-Varminter, built by McGowen, before there was a 22-250. The cases were made using .250/3000 cases.The RCBS dies are marked 22-Varminter.
When the 22-250 ammo became available it worked just fine in that rifle. Later the resized cases from that die worked just fine In a number of 22-250s I own and have owned.
If you are hesitant to a try a factory load or a modest reload, try chambering a factory load just to see if the bolt will close.If it doesn't you have an inadequate chamber. If it closes Just a little bit tite I'd say take the next step and pull the trigger. If it closes easily you may or may not have proper chambering.At this point I would go to the next step.
Try chambering a fired case from another rifle.. If it closes too easily we've learned nothing. If there is resistants in closing , full lenth resize that case and rechamber it. If your die is correct the bolt should close but you still could have some very slight resistance but that ain't all bad.

Start reloading. roger

Hey !! I didn't mean to kill this thread!! roger

Bartsche you didn't kill it but you covered the topic.
If it were my rifle I would try to chamber a 22/250 factory round and if it chambers I would fire it and compare the results of fired brass to factory, most likely same same...

I have a Gebby-built 22 Varminter that is a rebarreled and restocked Savage 1920 with a Lyman Target Spot 15x. The reamer that cut the chamber in my rifle was slightly different than the current SAAMI specs 22-250. The shoulder angle is slightly different, resulting in a slightly longer shoulder and a slightly shorter neck.

There is a slight difference on the older 22 Var. compared to the newer 22-250. The shop had the older 22 Var. reamers and gages and when the new factory round came out we had to change over to the new reamers. Check the Manson's Reamer shop to see if he has the difference in these chambers. It has been long ago and I can't remember what the difference would be. Neck dia. dimensions comes to my mind. Have it checked out with headspace gages. Remember that small calibers seems to blow up easier than the larger calibers. Know what you have before firing any rounds. I know of one case that blew the Fn action with a Mashburn made 22 Var. back in the early '60's.