How old are your pellets? They have a poor shelf life.
Swab between shots and see if that helps.
Shockwaves come with semi large OD sabot unless you get the Super Glide version. You could swap out just the sabot for
Harvester Black Crushribs and use the Shockwave bullet in them. That sabot should load quite a bit easier but not be too loose. Cabelas stocks that sabot if you dont want to order them online.
https://www.cabelas.com/shop/en/harv...abots---per-50