Problem with my 270's accuracy

POI jumping six inches left?
I have a 1950's Husqvarna Model 4100 in 270. I think it is a '57 It could be my favourite rifle except for one issue. It shoots inconsistently.

I have a matching rifle in 7x57 (1955) that shoots normally, that is; once sighted in, it maintains its zero.

The 7x57 has a free-floated barrel. For some reason, the 270's barrel is fit snug in the barrel channel. Tight in fact. Actually, the first time I tried to remove the barreled action from the stock I couldn't do it, it was so tight. I had it in to a 'smith for a slim recoil pad, trigger and safety work and then it was removeable.

Anyway, to shorten this tale, the last time I took the 270 to the range to sight it in after having the Leupold scope repaired (dropped it last year-long story) I had it group in nicely at 100 metres, about 2 inches high and centred, so then I tried three shots at 200 metres. I got a great group, barely 2 inches at 200 metres. That's good for me.

BUT- even though the group was at the correct elevation, pretty well level with the bull's eye of the target, it was six inches left.

I suspect that with the barrel tight in the fore-end of the stock that when the barrel warms up a bit, it expands and shoves itself against the wood, moving the barrel and thus the POI at 200 metres.

What do you think?

I'm no gunsmith or woodworker at all. How can I correct this anomaly?
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It is easy to float a barrel in a wooden stock. Judicious application of sandpaper will do it. Make it so a dollar bill will slip down the barrel. I did it to an old '06 that suddenly would not zero. Brought it right in. It might be worthwhile to apply a bit of oil (stock finish) after you are done.

 

Hard to say. Perfectly centered for 3 shots at 100 and 6 inches off at 200 really doesn't point to any particular thing. Certainly could be the barrel needs free floated, but normally you would see the rounds walking as the barrel heats up. Not shoot 2 perfect groups in different locations. I'd suspect the scope before the barrel. Make sure every thing is properly tightened. Free float barrel. Change scopes if it continues to do it.

 

I'm wondering if the scope repair failed.

 

It may be hitting the wood somewhere. Make sure your action screws are tight.
As others have said,free float the barrel. Check your bedding too.
Personally, I would get some Prussian Blue and see where she's hurting on the stock and remove a LITTLE wood at a time till you don't see blue on the stock.
By rights, Mauser actions should contact the stock at the recoil lugs on the receiver, with no metal to metal contact between upper and lower receiver.
IIRC, a lot of the Husky Mausers sold also had cracked stocks behind the receiver tang.
That was due to poor bedding and not enough wood relief behind the tang.

 

make sure the barrel, bolt, breech is thouroghly cleaned..it maybe building up some copper or some kind of fouling and its affecting your bullet. Dont neglect the scope, mounting screws and rings...they could be loosening up and or scope is not holding zero.

 

Get some different sizes of wooden dowel to wrap your sandpaper in works good for floating.

 

is the barrel clean?