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Outhuntin
08-07-2012, 06:07 PM
Bought a new tikka 243 this past winter and reloaded some shells and soon found out the twist rate was not right for my barrel due to the keyholing. So we changed loads and all seemed good. Now my neighbour who is an avid reloader moved to ft mac and i am in the position to either buy shells or reload. I had ran out and went and bought remington 100gr core lokts (thats the brass i shoot) and i cant group the shots. Two will group nice and then one is about 4-5" out. Is this just a poor shell or would i have damaged my brand new gun after keyholing. What are your thoughts on this?

Thanks

bigshell
08-07-2012, 06:28 PM
I highly doubt yer rifle is damaged,try a different brand of ammo or go to a lighter projectile.

Lefty-Canuck
08-07-2012, 06:33 PM
What twist rate does your rifle have?

If it is a 1 in 10 you might want to try a 90gr or 87gr bullet. 100gr will be right on the edge to work well IMHO....but it sounds like a bit more testing or experimentation is needed.

LC

Outhuntin
08-07-2012, 06:44 PM
Yeah it is a 1 in 10. My load was a 95gr nosler ballistic tip before this. I am using this gun for coyotes and deer so i didnt want to go too light. I went back to a 243 from my tikka 270 wsm so i would get more comfortable with the gun and shoot a lot of rounds out of it, compared to my 270 which i only used for bear and rifle season.

Smokercraft
08-08-2012, 07:42 AM
Federal Fusion has a 95 grain round for the .243. As far as factory loads go, you can't do much better in my opinion than Fusion.

Dick284
08-08-2012, 08:02 AM
Keyholing as in bullets going through the target sideways??

I seriously doubt those 95gr. bal tips would do that in a 1 in 10 twist 6mm bbl.

To me it sounds like you've got either a bedding issue, or are not letting the rifle cool down by the third shot. You may also have some issues with your optics and or mounts. There is also a chance you've got a buggered crown on the rifle.

Take the rifle apart and make sure the bottom metal is free from lubricants, also make sure you dont have a piece of debris lodged in the barrel channel of the stock or under the action, make sure everything is dry and tidy. Re assemble the rifle paying attention to the amount of torque your putting on the action screws, both screws should not exceed 40inlbs, and should be equal.
Check that your barrel is indeed free floated, use a bank note and slide it between the barrel and the stock, it should slip smoothly right to the receiver.

Check your scope mounts, the base screws(if you've got them)[I recommend this also] they should be torqued between 20 and 25inlbs.
Scope rings should be torqued between 15 and 20inlbs.

With all this checked and if it all looks good, re- try some groups letting the rifle cool out between shots (may take 5 minutes or more on hot summer days) if you get similar results, I'd be changing my scope out with another I know is a proven performer. If it still happens, I'd enlist the help of another shooter to see if he gets similar results.

If it still is happening try another brand of ammunition, and go all through it again.

Of course I am assuming that you are using proper rests, and bags, and consistant shooting techniques.

If all this fails..it's off to Bob at Custom Gunworx's.

Outhuntin
08-08-2012, 09:08 AM
Thanks a lot, will check out a few of these potential issues. I do shoot from a bench with proper bags. I was keyholing with A-max bullets.

Dick284
08-08-2012, 09:12 AM
Thanks a lot, will check out a few of these potential issues. I do shoot from a bench with proper bags. I was keyholing with A-max bullets.

What weight??

if it's 105's or heavier...yup it's keyholing, as a 1 in 10 twist wont stabilize those long bullets.

Outhuntin
08-08-2012, 09:21 AM
Yeah i am sure it was the 105. Sold them to a guy who shoots a kimber which will stabilize that bullet

Pioneer2
08-12-2012, 08:34 AM
Key-holing is caused but incorrect rifling twist for a specific bullet weight.Sounds more like a bedding issue.Have another shooter shoot the gun from the bench and bags as well...........Harold

1899b
08-12-2012, 08:41 AM
Key-holing is caused but incorrect rifling twist for a specific bullet weight.Sounds more like a bedding issue.Have another shooter shoot the gun from the bench and bags as well...........Harold

It is ALSO caused by shooting undersized bullets. I had an issue with a .38-55 once. Wouldn't shoot anything under .378 without keyholing. Twist is not the only thing that can cause key holing. I have seen factory Hornady bullets that were undersized from the factory and did not match the spec they were supposed to be and had to return them as they were creating a keyholing problem.

Pioneer2
08-12-2012, 09:12 AM
Many 38-55's are .380" when worn.A bad factory cut crown with cause erratic groups and fliers as well....many .303's shoot just fine with .308 dia. bullets for hunting accuracy especially if you want some in the 200-220gr size for moose + bear......Harold