I have 2 Glock17 gen5 T4E magazine and the punch pin or Bumper pin are damaged and need replacing otherwise it a new magazine and the not cheap.
I have searched the internet email Umarex USA , Germany no reply Umarex France said they only deal with French customers.
Have managed to get two only but there in instructions on how to replace them or any Schematic on the magazine, have dismantled one magazine but waiting when the pin arrives see if there a thread or push fit.
Reviews I seen on the net on the co2 leaking and it a common problem the pin gets distorted and leaks and yes I checked the green seal it fine but do have replacement seals.
can only reams to put one image on but i do an other post with the damaged one.
thank you Paul

My two Glock17 Gen5 T4E mags are nearly new but unusable ā the punch/bumper pins are damaged and Umarex support has been unresponsive.If anyone can recommend a reliable parts supplier or gunsmith who stocks replacement pins, please help ā Industry Leading Degassing Solution
I was checking out the Glock17 gen5 T4E magazine recently, and honestly Iām still not sure how reliable it is compared to the earlier versions. Some people say the feeding is smoother, others complain about jams. It kind of reminded me of when I was figuring out where to forward test emails ā on paper it looked straightforward, but in practice there were small details that made a big difference. Has anyone here actually tested the gen5 mags long term?
Thanks Paul. Strange that Umarex Germany or France wouldn't be more helpful.
New here, and still searching threads and forums. I look forward to any followups. Cheers