new build 9mm

just got this working well after many weeks of messing around , it was orignaly built as a pumper to see how many f/s i could get with a 9mm with a regular pump built in , the pumping got old fast , so i made up a tube which can skrew on and off so the pump can be skrewd back on . but when it takes 50 pumps for one shot (500f/s)…. and i have a scuba take siting beside me with air already to go , i just dont know if the pump i made will go back on .
so the guns is a 9mm , some of you will reconize the barrel , which seems to work great with my 124gr 0.355” slugs . havnt got any good numbers to post yet , but it will hit 500f/s on about 1600psi , further tests needed .
still got alot of cleaning up to do before it looks good but that will come later