Guys, looking for some advice and i know i'll get lots.
A friend bought a New Tikka T3 Hunter stainless in .223. It has Leupold scope and i think mounts. The gun shop fitted it all for him with a torsion wrench. He took it home and gave it a "couple" of turns himself...
We had a shot of it off sandbags and a bipod and we are getting 4-8 MOA with 50grain American Eagle factory ammo. I thought maybe the projectiles were fragmenting but the holes at 100m are the same at 25m so they are holding together.
I don't know what the twist is, so I've told him to get a heavier bullet try it, try another scope and try it. Apart from this i can't think of anything else that we can fix ourselves? (gun, ammo, mounts, scope) What other factors are there? (I haven't included shooter as i can put 5 shots in a 5 cent piece out of my .22 at 50m. Ahh, 5 cent piece is as big as your thumb nail)

Was the bore cleaned out properly.
Are the stock screws firm.
What shape are the groups, round horizontal or vertical.
Is the scope mount BASE tight.
Are the mounts correct/inline/not bending the scope.
Is the stock touching on one side.

By all means try different ammo and scope.
The tika is supposed to be guaranteed to do about MOA I believe.

Lots of Tikka .223s are 1:8 twist barrels, so the bullets could be the problem, but holes on the target would suggest otherwise.

I'd try remounting the scope, rings, and bases. The couple of extra turns may be the culprit. (What did he do this for anyway?) If it was to screws on the bases he might have turned one so far it's binding or pressuring the action. If it's screws on the rings, the scope may be torqued out of whack.

LWD

Also, are the groups consistent? Do they vary markedly in size when you wouldn't expect them to? If there's no consistency with the groups, that may point to something being overstressed somewhere.

LWD

Check to make sure the Objective lens of the scope is not in contact with the barrel.

Torque wrench or no, he shouldn't have been able to turn the scope mount screws. I'd take it apart and start over. Making sure everything is tight and nothing touching as I went. Another brand of ammo mightn't hurt.

I agree with stillbeeman !. When anything is mounted on a Firearm it should be tight , no slop in anything other wise repeatability is non existent . Try a different brand of Ammo also with a 55 -70 grain bullet . Doubtful the Scope is the problem Leupold builds real quality scopes .
I own a few my self and have NEVER had a problem with any of them even on my 338 Lapua Mag. Check clearance between barrel and scope Objective . Needs to be 1/8" or better .

When the rings are mounted with out the scope check to see if a ring alignment thingy matches up .

Shoot Straight Know Your Target . ...

Okay thanks guys, lots to try then.
Groups: Completely random. Some are near centre then another will be high left then high right. They bounce all over the place. None though are going low...Does this mean something?
Scope is clear and not touching anywhere.
He told me he cleaned it properly... as that was one of my first questions.
He's taking the mounts etc off after the new ammo and we'll find out.
(as for my .223, the permit to acquire is in. Now we wait, and wait and ...)
Cheers guys.

Yesterday at my cousins range he had a fellow stop by with his son and 2 friends. They were getting ready for hunting next Saturday. Three of the four rifles had scopes that would not respond properly to scope adjustments. There was a Tasco, Bushnell and a Simmons. The Bushnell had a ding in it near the turrets. The Tasco would hang upand needed to be tapped pretty hard in order to make any adjustment and the groups were all over the paper. All these scopes could be considered at the bottom of the price range. I have bought a few cheap scopes and only had problems when I had bad set of mounts.I bought a stronger mount and the problem was gone. I am sure that if we were not there to help them they would be hunting with those rifles next weekend.

Okay problem solved. Bought Winchester ammo with 55 Grain projectiles. It's shooting 1 inch groups at 150m consistently. Thanks guys.