What is the proper technique to avoid flinching? I find myself anticipating the shot occassionaly and ruining what would otherwise be a good group. Is this just a mental thing that I should try and shoot through with correct technique, or are equipment modifications in order (lighter trigger pulls)?
The single most important skill in shooting is trigger control. The best thing you can do is dry fire practice. I dry fire practice more than I shoot live.
If you haven't done it before, there is one critical thing to always remember.
NO live ammo in the area you are using for dry fire practice.
Dry fire practice allows you to practice trigger control without any stress of recoil, hitting your target etc.
You should take the same position you would take at the range, or hunting and concentrate on gently squeezing the trigger. I generally practice prone, off a table (bench) and also standing. I use yellow post-its with small black circles drawn on them as targets. In my basement, I can stick them on one end of the basement and practice from the other end.
When dry-fire practicing, make sure the rifle does not move when you squeeze the trigger. You should be able to see the jiggle caused by the firing pin and that is all.
As far as flinching. I always recommend double ear protection, as the sound is more likely to cause flinching than the actual recoil.
Another thing you can do, is shoot a 22LR and practice your trigger control (just like the dry-fire practice).
I'm sure there are other things, but these are the items that I always recommend.
AJ