I'm sure when weatherby confirms the gun sub moa they shoot the gun from a solid vise. I will have to say your problem isnt the gun. it is most likely shooter error.

I've used bags and all kinds of rests for years. All I can say is, in my experience, there are just a few things that can produce unpredictable results like it seems you're describing:
a: riflescope malfunction
b: mounting system malfunction
c: bedding problems
d: ammo inconsistency
e: rest placement.

You can fiddle with a thru d but sometimes where you rest the rifle foregrip on the rest can affect impact. If the barrel's free-floated (I think all weatherby's come with free-floated barrels) then check the barrel to stock clearance. I've had rifles where impact changes if I rest the tip of the fore-end on the sandbags, and then on subsequent shots, rest the rifle closer to the action. It's a less expensive thing to check out before you start paying for shipping or gunsmith services... Considering some of the other chamberings you are experienced with, I would tend to discount 'shooter-error' or flinch as a cause. Then again, sometimes a rifle can be just a "dog"...and I've had those too ! Good Luck.

As it turns out, Kreiger is right here in my back yard. SoI will have them take a look at the barrel to confirm that it is ok, then I will re mount the scope with Leupold mounts and re test. I'll keep you updated.

If I couldn't shoot any gun sub MOA I would consider shooter error, but as I said both my 30 378 and 338 378 consistently shoot sub MOA. and if I do get an occasional bad shot off I now exactly were it is. This is NOT the case with my 7mm. 3 shots that I consider perfect can be2 to 2.5 spread. Also the first two shots in the same hole, then all the rest at least 2 inches high ? Seems strange.

Contrary to what most people are made to believe the barrels used on the factory weatherby rifles are made by a company called Criterion which is owned by Kreiger.They are not the famous Kreiger cut rifled barrels.

Quoted from the weatherby website
[*]Free-floated Krieger™ Criterion™ 26" heavy contour barrel with longitudinal flutes to trim weight and dissipate heat (.705 muzzle diameter).

Quoted from the Kreiger website

Yes Criterion is a sister company of Kreiger. Kreiger was very helpful, they said bring it in and we'll take a look at it as well as having the guys from Criterion look at it.

Please keep us informed. Good luck with your rifle!!

I would start by ensuring that the action screws are tight. Then I would check the barrel channel. Is the barrel completely free floated? If not, any pressure points need to be relieved. Is the action bedded (pillar or glass)? Ifnot, it should be for best accuracy.Then I would check the mounts. Make sure they are tight. Possibly try another set of rings and mounts. Make sure the barrel is clean, clean, clean. Remove any copper fouling. Sweets 7.62 is the best copper remover I've found. Though some of the new foaming cleaners are very good, I like the Gunslick brand.

Then pick a very calm day to test. Missing a change in wind can really wreck groups. If you are not familar with shooting over flags and "doping" wind it can be a steep learning curve.

Try getting a friend who is a good shot to shoot it as well. I once had a "problem" gun. I did everything I could think of for it and it still wouldn't shoot for me. I had my buddy shoot it. He put five rounds through a jagged hole. I think sub consciencly I had given up on the gun and was wrecking my own groups. OBTW I ended up selling that rifle to my friend and it has shot great ever since.

Weatherby accumarks have an aluminum bedding block. The guy at Kreiger suggested getting it glass bedded. I did talk to Weatherby about that and basically they said you could do it but they didn't think it was needed. The barrel is free floating and I can easily slide a dollar bill through it, but it does seem to migrate in the channel somewhat. Weatherby changed their torque specs. on their triggerguard screws (decreased). Before this the barrel would stay put, but with the decreased torque as I said, it does seem to migrate a little, but remains free floating. I have not noticed any change in accuracy because of the change in torque however. If the gun would shoot consistent groups even 1.5 inch I would be alright with that. But it just seems something is wrong, or moving. If Kreiger/Criterion say the barrel is good, then I will try Leupold mounts. If still a problem I will probably have to sell the gun at a considerable loss. The last day I shot it was very, very calm. No felt wind at all. I did have another guy at the range try it, a stranger, but he did seem experienced with guns. His group was very similar to mine, not 1 inch, probably 1.75 to 2 but seemed quite happy with that.

I don't like the sounds of that one bit. Not at all. If the barrel is moving around then you have no chance of good accuracy. I think you just found the problem.Glass bed the recoil lug recess andthealuminum block. I bet that will solveyour "migrating" problem. You can't expect good results downrange if things are moving around in the stock.