Not very familiar with Wby cartridges, but I have an outfitter friend that wants me to build him a 257 Wby...Can this be done effectively on a 98 Mauser or mod. 70 action is my question..I looked at a 240 and that looks do-able, but I recall the 257 Wby is a larger case..so will a Rem 700, 98 Mauser or mod. 70 work and if not what will besides a Wby action?

Sure; .257 Wby is just a standard Magnum (.530) case, cut off to 2.5 inches. So any action you would build any other magnum on, you can do with a 257 Wby. As long as the OAL of 3.2 inches can be accommodated.

Just think of a 338 Winchester necked to 25 calibre or a 264 Win or 7mm Rem necked to 25.

Actually I find I amazing that someone who has been on AR for so long is not aware of what a 257 Wby is like.

quote:

Actually I find I amazing that someone who has been on AR for so long is not aware of what a 257 Wby is like.

Ouch!

If you are converting a "standard" action you will have to open up the magazine port. I haven't done it to Mdl-70 or the Rem 700 but have done several M-98's. Watch out that you don't open it up too much because you will loose the ability to stop the mag follower and it will pop up out of it's box into the action. I only did that once converting an 8mm, 98 to 300 mag. That required lengthening the port as well and then redoing the ramp. All of this is way too much work for me anymore. If it's not a mag action it doesn't get a mag chamber.