Help to ID mag

[guess_kto]

I got it with the other gun thinking it is for Beretta 92, but it's not. Too "fat" to fit. Design similar to beretta or sig, but it is not. 9mm, made in italy. Says "BP 9 mm". Pictures and all the text below:

 

[bps540]

wow, that's interesting..all the markings scream pietro beretta 9mm.
wonder if the magazine was bulged some how.
can't even blame a poor attempt at plugging the capacity seeing that it is only 10 rounds
to begin with.
i had a magazine issue with a beretta 96, turned out the grip screws stuck out a tad in the mag well when i changed grips.
loosened them off half a turn & no more problems.

 

[Harry Callahan]

It’s a Beretta PX4 Storm 9mm 10 round factory mag.