Tuning . 22 Taipan Vet Long owners

I have one of the subjected. It's more or less factory stock except for a heavier hammer spring, huma reg and add-on plenum at the air tube. It loves 23g H&N slugs ( .217's ). Like ... its 100+ yard accurate with them. 

They do get pushed around in the wind though and I'm toying with maybe testing something heavier ... jsb ko's for instance, or possibly even going a little heavier. The OEM barrel is about 550mm. Question for those of you who own one AND shoot slugs with it ... how heavy have you been able to push it while still keeping a decent shot count? Decent being at least 30 rounds. 
 
I've been able to shoot up to 32 gr. in my gun which is set up the same as yours. Heavier slugs than 32 gr. have all seemed too long to keep stable. 28 to 30 gr. seemed to be the sweet spot on the dies I had. The shot count is as good or bad as you want it depending on how fast you make them go. I haven't noticed any accuracy loss shooting slugs in the 700s vs 900+ fps range.

All the heavy slugs I've shot were custom swaged. I've had good luck with AVS slugs out of the ones I've purchased. I recommend trying the .217 cup based and getting a sample pack of the 26, 28, and 30 gr. to try out.