Read on the site where people were encountering hard bolt closing.  The problems were solved by greasing the bolt cam area covered by the shroud and the lugs. Give this a try, it solved the problems of others on ghis site.

For my 223 Tikka, 1:10 twist,  I have found 69gr SMK are tack drivers. I use Benchmark's max load.
One quirk about my rifle is that when you get the barrel squeaky clean, it shoots poor groups.  It does not shoot good until it has @ 100 rounds run through it.  Once you get it shooting good, don't scrub the copper out. Just wipe it clean with an oi… Read more

For my 223 Tikka, 1:10 twist,  I have found 69gr SMK are tack drivers. I use Benchmark's max load.
One quirk about my rifle is that when you get the barrel squeaky clean, it shoots poor groups.  It does not shoot good until it has @ 100 rounds run through it.  Once you get it shooting good, don't scrub the copper out. Just wipe it clean with an oi… Read more

I have a tikka 223 varmet 1:10 and get 1″ groups w/ 69gr.
smk