RE: 209 primer selection for inlines?
The only time a reduced-power 209 primer works well is with low-mount scopes mounted over an action that produces a lot of blowback from ignition.
If you want long-range shots (beyond 150) the hotter & faster ignition (777 & Federal primers) works best to consume more powder & increase velocity. ... accuracy may not be included so practice.. practice.. practice those shots.