i have 17 rem.that is keyholeing. the load is 23.8 of varget and a 25 grain v max bullet.the gun is a tcr hunter with a ssk barrel.what is your advice on what could cause this and fix thank you for help.

this is a tough one., Usually keyholing is a sign of under stabilization. With that load it shouldn't be doing that. Try a shot or 2 using a 20 gr bullet. I might be that the twist is inadequate, in which case it would be time to return the barrel, with a suggestion of where to place it

I don't recognize that load so don't know what your velocity may be, but my .17 Remington got very innccurate when velocities were too high.

I had one load which was an absolute ace when shot in November through February...well under .5 MOA on a reliable basis.

Then, as seasonal temps warmed, it would begin shooting bigger and bigger groups as the ambient temps rose. In April it would begin showing "flyers" when the typical daily temps were up to the 60s and maybe mid-70s.

By June it would be grouping 1 MOA or larger, regularly.

When late July and early August arrived, at least half the bullets would never even reach the target. With the increased temps and increased pressures caused by those temps, the cores would melt out of the bullets in flight and they would blow up about 1/3rd of the way to the target.

On reflection, it became apparent that the cores were becoming at least partially melted back in the April, May, June months and the bullets were becoming unbalanced in flight, resulting in first the flyers, then the generally larger groups as the temps continued to rise. (As the partial melting became more frequent as the weather got warmer, the groups went from having one ore two flyers per group to almost every shot being a flyer in one direction or another. Hence, substantially bigger groups.)

I know that all sounds like fantasy, but one needs to understand that even in the dead of winter, that load with a hefty charge of Re7 was chrono-ing at an average of over 4,400 fps with its 25 grain bullets.

So, you might try reducing your load about 5% to see if that helps. It may not, but then again, it might.

(Of course, if you are using monometal bullets,none of the above applies to your instance.)

Unless the throat is shot, the most likely cause for this is due to metallic fouling in the barrel, it causes the tiny .17 bullets to 'strip' the rifling and cause tumbling. I had the same problem in my .17 years ago, a good thorough clean always managed to fix the problem, until the throat was gone, of course. I got 2000 rounds out of my first barrel, and over 3000 from the second barrel.
I am positive this was due to a consistent cleaning regime on my part, I would clean after every 20 rounds, whether accuracy had started to drop off or not, and it was easier to clean as well as time went on.

Cheers.

thx for the help. 20 grain V max did the trick.