Ken, I know my BT65 (.177) has a choked barrel, I believe they do in all calibers. I was having difficulty finding pellets it really liked aside from JSB's. The next closest was Daisy hollow points (soft lead), but couldn't/wouldn't detune enough for stability beyond 35-40 yards. No luck with anything H&N in that gun, too many flyers. Luckily it liked NSA slugs, so that's what I've been using since...
Seems .30 and.25cal pellets do very well in the 100 yard matches, slight edge going to the .30, could only imagine sized slugs doing better if they take to the barrel. Don't have the expirence with these calibers to say for sure, my only .25 is a break barrel used for short range pesting...
With .22 caliber pellets even the slightest breeze of ~3mph affects trajectory at distance I've found. The 18gr pellets I've used perform similar to the 15.9/16gr pellets when pushed into the high 800's/low 900's. If anything they might actually perform better at 800-850fps from lower powered guns.
With a headwind, the POI will raise some using pellets. Cross winds will drift left or right and you might find up or down some depending on the wind direction, as the pellet "walks" on the breeze (pellet rotation acting on the wind). It's fun getting out there, but can get frustrating. The guns will tell you what they want to shoot, but if they choose slugs your job will be slightly easier behind the trigger.

There are others with much more airgun-long range expirence, hopefully they can get you pointed in the right direction for you're specific guns/calibers.