Strange groups

[IceSniper]

Today i shot a few 3 shot groups with my .22lr at 50y and i noticed something a bit srange, On every group the third shot would land 27-30mm left of the other two

. With my last five rounds i left it 1 minute between shots and my group was 12mm center-to-center for 3 and 20mm for 5.

Any idears on what gives? I figger it must have something to do with heat (not that a little .22lr gives off much).

Thanks

-Ice