What kind of powder you using ? If triple seven or pyrodex , change powders . We had the same problem with shockwaves not expanding , not enough velocity . If you're not already using BlackHorn 209 , then by all means get some . Couldn't believe the difference in accuracy , cleaning and bullet expansion .
110gr BlackHorn under a 295 Barnes knocked an exit hole about 2.5-3" wide with a behind the shoulder shot . Lungs were pulverized .
The BlackHorn according to charts is giving a little over 2100fps with that bullet .100 grs was pretty accurate but 110 was better with most groups going about an inch . Also the blue sabots, ez load were easier to load and more accurate . Do not use ML 209 primers with this powder , results are terrible . Make sure you use magnum shotgun primers , powder requires a hotter primer .
Friend has a CVA Wolf and he is getting better accuracy around 80 gr using 250 gr bullets.
Mine is a Knight .
Just thought I would mention this about the powder because you said takes about 30 seconds to see , BlackHorn doesn't make near that much smoke and way easier to clean .
Also found that Federal bore lokts 270 gr give excellent accuracy. They also expanded well with pyrodexand triple seven . Haven't shot any game with them over the BlackHorn, but they should be good .
Have a good one , Kenneth