Have an opportunity to help a buddy put a gun together, but his needs and wants pull him in different directions for caliber. I suggested that we use a savage action for a switch barrel setup in .300 WM and ??? He wants the primary cartridge to be a bit cheaper and easier on the shoulder. I initially thought .270, but wanted to get some input here. Don't the WM and the .270 have similar trajectories? If I start with a WM rifle, can the .270 cycle from the mag well? Have to swap followers? Planned to buy the barrel for the smaller caliber as it will likely see more use, and might go with something a bit heavier than standard. The .300 would just be for an occasional elk trip. The rest of the shooting will be everything from varmint's to MO whitetail.
Your choice of platforms is excellant. I might add that choosing a cartridge based on the 06 or .473 bolthead size seems to be a better choice.
At savageshooters.com you will find many doing every day what you are asking about.
By choosing the .475 bolthead you can load in the standard magazine without issue, a 22-250 or 243 for varmint. 243-270 for deer and maybe a 338 X 06 for the occasional elk or bear hunt.
Rifle takeoff barrels ARE READILY AVAILABLE for 0-$200. I usually pay $45. for about any caliber I want. I have a bunch of Savage takeoff barrels and every one of them shoots great.
270 isn't even on the same level as a 300wm and the 300 is not that hard on shoulders or barrels unless your a 10 year old kid! IMO if you stick with an 06 derivative first pick would be old faithful 30-06, then 280, then 6.5-06. 25 and 27 cal bullets suck and the wildcats are to heavy for that cases and are not usually of the best design and require much faster twist rates. Good luck.
Just go with 270Win. It's an awsome elk getter, even with 130gr bullets. You could just do different loads for different aplications.
I'm not against the switch barrel idea, go with detacable box magazines that are set up for the different cartriges. I would think a good center feed set up would have the least problems. I would use a second bolt for the other cal.
I use 300wm for all big game. I think the 270 my cousin uses makes bigger holes. I didn't actually use a tape measure, when the .300 180 SPBT Hornady has quarter size exit hole and the .270 130 GS Speer has a soda can sized exit hole there's an obvious difference.
There are only two seasons: Hunting season, and Getting Ready for Hunting season. -DAD