Well I just read all the posts about getting the Mkv Ultalight to shoot and also the Tikka T3, so thought I would put in my experience with both rifles as the Weatherby Mkv is my favourite brand of rifle followed by the Tikka T3.
I have two Mkv UL's. One an older wood blued in 25-06 the other one is a current synthetic in .240 WBY mag.
When I bought the wood blued 25-06 over 10 years ago I could not get anything that would come close to being accurate. Nothing would group under 2 inches. So I bedded the action and floated the barrel. Next it took quite some time to find a load that would eventually shoot a decent group. That load is the 115grn Ballistic Silvertip ontop of 55grains of AR2213sc. Groups ended up being half inch or better! To this day that rifle is close to my favourite gun and still shoots great. But it will not shoot any other load decently enough.
Next up is my 4 year old synthetic Mkv UL in .240 WBY. From the moment I pulled that rifle from the box it shot everything close to half inch groups. There was no messing about having to bed it or take the time to carefully tailor a load. She just shoots great!
Especially with again a charge of 55grns of AR2213sc but with the 6mm 90grn Swift Scirocco ll projectile.
Then there are the 4 Tikka's that I own. A SS in .243, Wood blued in .260, Camo Stainless in 7mm-08 and the Laminated Stainless in 7mm Rem Mag.
Now everyone of these rifles shoots anything you put in them, factory or reloads, absolutely perfect! I have played with another 10 or so Tikkas as well and not one of them has shot badly. I do not know what it is about Tikka's but they just seem to shoot straight regardless!
So there you have it, my 5 cents worth. Although I am a dead set Weatherby man owning quite a few and plan on owning them all, if I cannot afford a Mkv then the next choice is more than likely a Tikka T3..