Glock mag question

[GW]

Will Gen 1-3 mags work in a Gen 4?
Vice versa?

[Lumpia is sarap!®]

Yes.

[billped]

Work? Yes. But Gen4 are reversible so you need them in a Gen4 to get full lefty capabilities.

I hope I have that right. :-)

[GW]

Thanks
I might be able to acquire a Glock-40 and I have a G-20 with a bunch of magazines already

[RoundEye]

As other have said the only difference between Gen3 magazines, and Gen4 magazines are updated followers, and that they're ambi. If you're right handed, you can use any of the older magazines in the Gen4 guns without issue.