Rebarrel/Rebore 338 WM Alaskan to 450 Marlin or 350 Rem Mag

Hello Savage experts,
I have a Alaskan coming in 338 WM. Thinking about turning it right around and sending to be re-bored (keeping the factory irons) or re-barreled and adding iron sights. I want to keep it in the 20" range and rebore it for a heavy cartridge that suits the 20" bore better. I have doubts that the 338WM was the best choice with a 20" barrel. What I am most concerned with is the action length and what my options are. I did look up the list of bolt face diameters and I saw options like 458, 358 norma, 350 rem mag and 450 marlin. To rebore I imagine having to go much larger due to the original chamber size. Can you help me understand what is possible?

What do you intend to hunt with the rifle? A short barrel 338 is more than enough gun for anything in North America, seriously. I'm putting together a FCP-SR in 450 Marlin right now just because I wanted a nasty short action with detachable magazine. You could put the 450 or 458 in your long action if you think you need it. For the cost, I would just get another barrel if you want another caliber, that way you can switch them if you want.

I was thinking that the 338 in a 20" barrel would be too short to efficiently make use of the powder, leaving some unburned powder on the ground. I may be wrong. What happened is I low balled a gunbroker auction and won the danged thing. This is kind of a dream gun for a dream life I would love to return to in Montana. I currently would only have use for it on hogs here in South Georgia. I just thought that the two aforementioned caliber choices would make better use of the barrel length which is why I bid on it to start with. Both also being a good hog/bear stopper. However if you guys believe that the 338 would do okay in its 20" configuration then I would keep it as is and would love it's inherent flexibility as an all purpose caliber choice.

I was looking for comment and realized after I reread my post that I didn't ask a question. So, what do you guys think about the 338wm out of a 20" barrel? not the right caliber for a 20" iron sited brush rifle?

For a dangerous game rifle, I think it'd be just fine. I like the 350 Mag, I have 2 and will be building a 3rd soon. The 338 is an impressive round, and it ought to throw one heck of a fireball out of that short barrel. If I had one in the safe, I'd leave it as is.

Good advice. I think I will leave as is or sell for a custom 338/06 build. I've been reading about the 338/06 and see a lot of upside, reduced recoil being a big one and ease of converting brass being another.