I will be trouble shooting 4 things next time at range to narrow down what the issue is. I will start by shooting the same way that grouped well last time to verify I have a known good method, then take away each variable and see when the group falls apart. I will take away ONLY the listed methodology for each group, all else will be the same as the reference method.
#1 Referrence group, From sled standing behind bench, each round hand loaded to chamber, 150gr fusion, barrel cleaned before each shot, 5 minutes between rounds and 15 minutes between groups.
#2 Take away hand loading rounds and use Magazine
#3 Take away cleaning barrel before each shot
#4 Take away letting barrel cool, will take about 90sec between rounds due to cleaning between shots. will continue on firing after group #3 without pause other then to clean barrel. This way first round will be from warm barrel.
#5 Shooting from sitting at bench off of sand bags.
Originally Posted by JeffP40
That one group does look promising. One thing you still need to try in my opinion, is cleaning. #9 does squat, there's nothing in it any longer that takes the fouling to clean steel. Use at least sweets, shooters' choice, mt extreme, wipe out, or bore tech. You have to get the copper out of the imperfections in order to let the next bullet continue to "lap" the barrel.
One thing about bench shooting. The rifle may like to be held tight, or loose on the bags. Somteimes free recoil groups good, sometimes a firm grip works. Keep trying.
I don't want to change how I clean the barrel between rounds yet, but if I find that cleaning the barrel is what is allowing the tighter groups then I will definately get some good cleaning agent and try break in process if I can't get Tikka to take the rifle back and fix the issue.
Best case senerio is that just one thing is causing a huge impact on group size.
Worse case is that I find 2 or 3 things are causing modest variance that when combined create a large variance in group size. ie Chambering from Magazine, barrel temp, and dirty barrel combined cause a 1" jump in group size.