The gun store guys put together one with parts you can find at any hardware store:
Testing it out:
Wow, that works really well. I’ve seen bumpfire stocks people have made in the past, but they all looked pretty unsafe to me. This one looks a lot safer since the bump shaft is metal and secured on really well. The one thing A person could probably do to make it safer would be to put an endcap on the end of that bump shaft so you couldn’t loose control and have the glock slip off.