Lightweight bullets pulling left?

Hi -

I took my Mk. II to the range tonight with a sample of six different kinds of ammo, to try and figure out which my rifle likes. For the record, CCI Mini-Mag and Winchester Super-X RN 40g were the winners.

Anyway, I shot twelve targets, ten rounds on each with each of the six types, twice apiece. Among the 36-40g RN bullets, both lead and plated, I also had two hollowpoint "accelerated" rounds, the Remington Yellow Jacket and the Federal accelerated hollowpoint. For both of these (4 targets/40 rounds total), the groups were WAY left - like two inches at 50 yards, compared to the other 8 targets.

Is this an indication of anything in particular? Is it just a difference in point of impact due to the different velocities, or does it mean something about the barrel/stock alignment, or anything else obvious?

This is a standard Mk. II pre-Accu-anything, about four years old, using a 4x scope. It doesn't shoot what I would consider "great", but is certainly acceptable at about 2-3 MOA off of a front bag. Standard plastic stock, haven't fooled with it at all.

Tx!

KeS

its just the differents in velocity to the point of impact.

Kes I have the same basic rifle only with the laminate stock and it just loves CCI standard velocity. It shoots the american eagle just a little right of poa and the federal gold medal (way to much $$$) to about the same poa.
It does not like the high velocity rounds at all.