Thread: First attempt at reloading. Thoughts please.

Ah, kemo sabe.
I'm sure all of the above are wiser shoulders and older heads, but I will give you my few cents worth.

You are trying to discern the dark arts of internal ballistics.
Unfortately these are generally discerned by measurable external ballistics.
As above your "good groups" or "near nodes" are somewhere between 40 and 42.5. No animal in NZ is going to notice the difference.

If you want to chase fraction of minutes of angle... you should weld the rest of the barrel back on and do what all the benchrest guys do.

I migh also suggest, if you can find it, 2206H might give better performance.
If all else fails, upgrade to a .45 (11mms)


-edit: I usually start and finish "20 thou" off the lands. Regardless of cartridge or manufacturer. (milsurp excepted)
Tikka are very well made rifles,
and the poor Finn that made the 7 inches of barrel you've so wantonly discarded is probably going to cry himself to sleep tonight.