How much vertical were you getting? I assume it's a standard high power silhouette pig?
At 500 I think the trick would be spotting your misses until you really learn how they behave in subtle wind changes. Those .22's are probably about twice as wind sensitive as the black powder bullets I shoot, and it's pretty easy to get off target with those. At 500 a 10 mph full value wind can take you off a 36" circle if you were holding dead centre. The trick is catching the little changes.
I've only shot my .22 out to 200m, but that's no real trick with quality ammunition. The RWS R50 seems to hold elevation best for me. We use rear sights with tons of elevation, or scopes with external adjustments that often have 150+ moa of range.
Chris.
139 moa +or- a few moa would require a select system to get that far.
