Peashooter...I played with um too when i first got slug bug bit.. MK3 wildcat compact .177 xl plenum on a tube gun.. very similar platforms, mines just half the volume..Im guessn.....gun was tuned for 10.4 atomics..lol. not slugs....178 nielsens, ?wildmans, H&N's and 177.5 zans.....straight...