I had one in the 454. I think I shot two 454 through it and then went to light loads of 45 colt. Very goo shooting gun. I didn't really have a need for it and didn't shoot it much so I traded it. It is really good using the same trigger unit as the GP100. It was much better than the 45 colt Redhawk I had. It had a terrible trigger and busted my knuckle when I shot it. The Alaskan was much better.
I had an Alaskan and also a 7-1/2" Redhawk in 480 Ruger. After a couple of summers of load development and shooting them, I discovered 2 tings: 1) when shooting at the range, 20 shots was enough, and 2) I was getting 1250 FPS with 21 gr's of 2400 and a 365 RNFP bullet when shooting the 7-1/2" gun and the same load yielded 1025 FPS with the Alaskan shooting the same load. Surprisingly the Alaskan's recoil was not any more brisk than the 7-1/2" gun was. There are more powerful handguns out there to shoot, but I think the .480 is about the limit for most shooters. I sold them both to concentrate more on other guns.
I do not own a Ruger Alaskan 480, but I have a Super Redhawk 9 1/2” target gray model. I load this revolver with H110 and a 400 grain WFNGC cast bullet (BHN-22) with a velocity of 1103 FPS. Really does a great job. It is my favorite hunting revolver with a reasonable recoil compared to the 454 Casull or the 460 S&W….IMHO