OK, so I got a few tips on the rifle spinner now on to the pistol spinner !
I expect to see a pistol spinner in my next match and I've never had the opportunity. I've watched several youtube vids for tips and I think I'm squared away but one can always use more good advice for these things. I watched a vid from In Range TV and in it they compared 9mm 115 and 124, .45 auto and .50 GI on the spinner.

It was obvious that the 300gr .50 GI made the biggest impact. My choices are limited to 9mm 115 and 124 and .38 super auto in 124 and 130. So I did some testing with my two 8" steel plates hung together on the same hooks for maximum weight. My sole judgement instrument was my own eyes. At 15yrds the Wolf 115 made almost zero impression on the plates, barely registering movement. The 124 @ 1100fps made for some movement. Greater movement was observed with .38 super using a 124gr @ 1200+fps and even more using factory 130gr, velocity untested.

My next test will be using 9mm 124gr NATO spec [1200fps ?] and, if I can get some, 147gr out of the .38 super.

My question is do I want a little greater impact at the expense of fewer rounds [10+1] or more ammo [18+1] and less impact? I do know a guy who has shot a pistol spinner at the same match last year and he timed out at the expense of 42 rounds fired. He purposely used factory 9mm NATO spec ammo !