I went to the range today to do some testing. I took the bren with the 12 mags I got from IO and one of my mg42's. A little while after we got there it started pouring with some really intense lightning. Everything got soaked, the case with the bren mags had about 3" of water in it and all the loaded mags were full of water. But they worked, only 2 of the 12 had some problems. The 42 needs a new mainspring, it is binding on one of the front coils that has a kink in it, and the feed cover has some issues. But at least the rest of it is ok so I can blast, park and final assemble it.
here is the video:
brenvideo2