You don't need a special gun to shoot any particular shotgun sport.
Yes, if you get very good and continue into registered shoots and matches you will want to be able to squeeze every possible target/point out of your ability. A 'better' gun can sometimes do that. But not always.
Like rifle and pistol shooting it can become a search for gimicks it improve your ability.
A decent Field gun that you are familiar with, feel comfortable with and shoot well,,,what else do you actually need at this point.
You are going out for some fun and good times.
Special loads won't help you either.
Keep the Velocity at 1200fps and under and you'll be comfortable & be in compliance with most all of the Clay Target rules I'm aware of.
A 1300fps or more load will allow you cut you lead down 6 inches or so on a speedy crosser out there.
Big deal.
Interchangeable chokes?. Get 'em if they are already on the gun I guess. I see it as you are stuck with them at that point.
I see no need for them.
Just shoot with what the bbl has.
All the shotguns I have are Full choke with a couple coming in at Mod on the right bbl of the SxS.
I shoot Skeet mostly w/ 2 Trap pump shotguns and a SBT gun.
I don't think about the size of the pattern, # of pellets, velocity,,
Just shoot to the correct mark and you will break the bird.
The Tight choke lets you break them out the a ways. I always shoot the Doubles in Skeet 'backwards'. There is no problem breaking that second bird out at 40yrds with the light load and a Full/XFull choke.
But if I don't shoot to the correct mark/position/lead/ keep the gun moving,ect, I will miss just the same as if I were shooting a SK1 choke at an incomer at Sta7.
My reloads in 12ga have been 5/8oz shot for the last 20yrs.
The orig Lyman Manual recipe was for 7/8 oz. I just kept reducing the shot load.
I used to load Clays powder that the recipe instructed to use.
Then when it became scarce I switched over the Alliant ClayDot. Good stuff. I think the load is 14,4gr.
About any primer I can find,,mostly CB1100 wads, but I use others I find here and there,,,about any hull. I load them all the same.
I pick up the hulls at the gun club. It's like picking up brass, can't leave the good ones behind even though you have more than enough already at home for a second lifetime.
I even reload the rollcrimped 'Slug' emptys I find on the rifle range in the Fall. They run through and take a STar crimp just fine.
One piece hulls I sort for the pumps. Two piece hulls (separate base wads ) sorted for use in breakopen guns. I always check the bore(s) before reloading for obstructions.
The extra space in odd mix of hull brands & wads I take up with a couple Cheerios on top of the shot before crimping. Makes for a nice uniform crimps.
I see no reason to change. I use them for Skeet, Trap and SC.
Low recoil, they break everything I hit. Easy to load and easy on the elderly guns I shoot.
Have fun, stay loose,,come Home with a Smile.