Your questions are a little generic for specific replies.
This rifle has been lights out and remains accurate but getting up in round count.
How many rounds fired are on this barrel?
Has the accuracy started to show a definite decline in accuracy. If yes from what to what?
Is the barrel starting to be harder to clean? (build up of fouling and maybe carbon, fire cracking)
Generally speaking, when a factory rifle barrel approaches the end of its accuracy life, there is very little reason to consider alternatives to outright replacement. If your current accuracy is showing a decline, I suggest simply replacing it.
If you do replace it, you have the option of using a slightly faster twist rate such as a 1:10" twist although the box length limits the use of longer, higher BC bullets.
Options include:
Setting the barrel back to allow for a minor improvement in the throat and freebore. The drawback here can be the lack of tenon length since factory barrels often use the minimum specifications in manufacturing to save money and weight (shorter tenons). Another deterrent is using a good quality reamer for cutting through potential carbon build up. Many gunsmiths don't like running their reamers into a carbon crusted barrel.
The problem you really need to look into is the magazine overall cartridge length. Tikkas are limited intentionally to the shorter length. The current trend towards the longer, heavier, higher BC bullets will generally exceed the maximum box length. I suggest calling Red Snake or Wyatt's to get the end all answer.
Best of Luck!
, pick your new caliber if you have one in mind Or keep it 300 W-mag,start reading about Custom barrels and Manufacturing of them barrels,next call and talk to Gunsmiths to see who will work on your Tikka/695 action there's much talk of pre fit barrels for the tikka T3 ask or call good luck Cheers!!!.
