Depends... Let me explain...
Are you going to have it built or due it yourself. If you are going to have it built talk to the smith doing the work and go with is recommendation. That way you don't get the "I told you" attitude if there is a problem.
Now if you want a do it yourself project I would definately use a Savage action, and have. Only thing you need to do is decide if you want a singe shot or repeater. Barrels are easily installed with a minimal investment in tools. Find you don't like the whisper, change the barrel to something else.
Here is a link to the Savage Users forum
http://www.savageshooters.net/
There is a fella on there called Northland that sells actions, stocks and such and is good to deal with. I have dealt with him in the past and Jimmy is OK.
Lots of info here on Savage guns and friendly folks to boot.
As for twist, again it depends. Wanna shoot subsonic or hang a can on it (silencer) they 1X8 is mandatory to stabilize the 200 gr+ bullets at subsonic (silenceable) speeds. Gonna push heavy light bullets (168 gr or less) at supersonic speeds then you can get buy, in most cases, with a 1X10 twist. If you order a custom barrel I would go the 1X8 cause it allows you to do both. Barrels are availble from a number of folks try checking out folks like Sharp Shooter Supply ( I have dealt with these folks and they are great) or Pacnor (never dealt with them but they have a good reputation).
I hung my barreled action in a Ultimate Varminter Stock from Choate. Took a day or two to assemble when I got all the parts together. I have since put together a few more savages in various calibers. They are easy to change and accurate.
Finally if you are considering a semi auto there are number of folks, Model 1 Sales comes to mind, that offer AR15 uppers. These are compete and ready to go. I have on and have been pleased with its performance (it has an adjustable gas block which is a requirement for shooting subsonic), 1X8 twist barrel, shoots and functions very well.
So there you have it... My $0.02 on getting a 300 whisper..
Hope it helps, drop me an email if you have any questions...
DonT
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