Layton,
I have had two 5 grooves shoot right under 1/2moa, but everyone of my 4 groove 260s shoots 3/8ths or better. Normally in the .2s, and my Polarbear 2.0 rig is in the .1s after the 20th round down range.
My first KMW 260 was a 4 groove....that thing was the magic stick. I am sure it...