Thread: 7mm rem mag Tikka T3

I'm not the most expert in this but:
If you personally shoot good 500m groups with the 270 and with the 7mm shoot good groups at 100m,
(ie it goes from 100m cloverleaf to 500m metre group and back to cloverleaf in the same session. If you shoot 2cm at 100m its reasonable to expect 15-20cm elevation at 500m using the same setup but could easily get 50cm spread for windage.)
then its likely this factory ammo is very high quality for the factors affecting 100m accuracy (concentricit and bullet quality) but somehow doesn't fit your rifle for the longer range requirements (cartridge headspace and case base to ogive). I think its unlikely they've got a problem with neck tension but it could be their outside neck diameter doesn't match your chamber. Probably the ammo will perform well in a range of other rifles. Its unlikely your tikka is suffering from overheating during strings. Their guarantee is only for 3 shots but they dont wander or walk when shot hot.
Parallax can give problems at longer range if not adjustable on the scope. Some are set to 100m, which will cause variable impact at longer range if you don't have good cheeeck support.

Not many people rely on factory ammo at 500m.