Tikka T1 X and question

[Allen in MT]

Got the KRG on the T1 X, 419 30 MOA rail, Vortex PST Gen II 3-15X44 FFP MRAD, Stock trigger. 25 yards Center-X. Took 5 shots to get scope sighted in. 2nd 5 shot group a bit low, 3rd 5 shot group after scope adjustment on the cross. Used magneto speed to gather velocities.
The bottom line is 5 sight in shots. The top 2 lines are the 2 - 5 shot targets in photo.
When figuring a dope chart for distance should I pick the highest vel info or add the info of all three together and divide by 3.
Didn't get a chance to shoot farther today, That will come later as weather permits. Spent 22 case in 4th pic.

 

[Near miss]

The effects of ES at long range and how to count them in without giving ballistic computer false data or hand picked data.

I take the average velocity of all rounds. Except usually first shot is faster and second slightly slower than average so you might want to clean them out.

I do this rather unmanipulative action because to create a temperature table which means to note the velocity at different temperatures, a unified input method must be in place.

I have many times tested if the average changes if I take 5 most extremes at both ends. But it sticks, meaning that the extremes are built in to the ammo quality. (It does not have 1% of ammo that just run 3% hotter than others or some other trait, the faults are totally random, thus clean built in to manufacturing process)

About temp of ammo, be careful that when testing MV of your ammo that it is the same temp as ambient air and not in the sun and be mindful that during a range day the temp might change quite a lot.

For me, I take at least 30 shots to get real results for ES and it also gives very solid information about the average velocity.


Then to the actual effects of MV variance at long range..

I just run 100, 200 and 300 with the temp table function in Kestrel turned off and see what kind of vertical spread is inevitable. But that does not necessarily serve any real purpose, since you cannot expect every outer vertical to be a bad load, unless you have chrono to prove it with.

I just accept there is inherent inaccuracy built in and that is not due to ammo being rimfire (does not help it) but more because all subsonics are very prone to any MV variation as the lower the go, the more bigger part the MV variance takes in POI.