I was at a little Wisconsin shop today, and picked up a well sporterized Remington P17. It was too cheap to not buy at $275. The barrel was shortened to 20 inches, and never crowned. I was thinking of just having it crowned and keeping it as a 30-06, but also am toying with the idea of having the (military) barrel bored out and turning it into a 35 Whelen, simply because I have never owned one.
Any thoughts on a 20 inch Whelen? What twist, 1 in 12 or 1 in 16?
I'm open to any random thoughts. If I decide to re-bore, any suggested shops?

I wouldn't spend my $$ having a military barrel rebored. You can have a new one for installed for basically the same price. I like the Whelen but I would also like a touch more barrel. If you go with the rebore I would go 12 or at the most 14. To me 16 is too slow.

I was under the impression that a rebore had to retain the original twist...I could be wrong. In any event, I wouldn't bother with a rebore of an original military barrel especially one that has been chopped to 20 inches. Just buy a new 35 cal barrel and have it installed.

My $.02

Edit: After seeing Paul's reply, I realize my advice is only worth $.01 (if that).

A re-bore cleans out all the rifling so any new twist that the boring machine can do can be done.
Barrel length; your choice I guess, I like them long on the Whelen. You can get a very good fellow to re-bore your barrel at http://www.35caliber.com/ at quite a bit less than a new fitted Barrel. 1 in 14 works well with about every bullet but he can guide you in that too I would think.

A Whelen needs a 24 inch barrel to perform to its capability IMO..I also prefer the IMP 35 Whelen and the Brown Whelen is the best of all if your so inclined to the trouble of fireforming..

I'd just crown it and shoot 220 gr. bullets if you like the whelen, that's pretty close balistically. Otherwise get new barrel.

Yup, go with a new barrel at 24" if you go the Whelen route. I'd only rebore if there was an expensive sight set-up I wanted to retain or if the barrel had a full rib or something, otherwise it doesn't seem cost effective. I have the improved version, but if were to build one today I would go with the plain vanilla version. Just not enough to be gained to justify the extra work(fireforming). Solids do look cool in the improved case though...