I have tried to run 200 gr SWC in my 21 and my 30s but have had issues. Most will cycle fine but every so often get a failure to go into battery and have to smack the slide to get things going. I do use a Dawson case gauge and they pass. Would assume my oal is off but can not find the sweet spot. These rounds work flawless in my 1911.
Have given up on Glocks and SWC and use FP or RN.
Maybe some smart guy will solve the issue and I can use them. I love SWC in competition as the "flying ashtrays" make the best holes.