Sig 522 Modifying Magazine to Make Drop Free

[SayNo2NWO]

I recently bought a couple Black Dog 10 round (smoke) magazines for my wife's Sig 522, but found they would not drop free. A slight modification with a dremel (or file) got them drop free. Pretty simple, just need to file the two opposite sides where the rounds are loaded (as shown by the pen in the pic) to make that width just SLIGHTLY narrower.

[Flyingpootang]

Did you file the inside or outside?

[AlbcAlbrr]

This is going to be kind of negative, but that's the weakest part of a Black Dog Machine mag. The feedlips are already prone to chips and cracks. You're pushing your luck with a mod like that, so good luck with that.

If it's too tight maybe it's out of spec. and should be sent back to BDM.

[rrr70]

All ten round BD mags are like that. It's not even filing off, it's more like polishing. You just have to remove less than 1/4 of millimeter. It doesn't affect mag in any way. Regular size mags a drop free out of the box.

[SayNo2NWO]

Not quite sure what you're asking, but you file right where the pen is touching in the picture and on the same surface opposite side.

[SayNo2NWO]

Yeah, well I live on the edge anyways, prone to pushing my luck, but in this case, no luck necessary. Works like a champ. As rrr70 pointed out, standard capacity mags come drop free, the Black Dogs 10rds are just slightly too wide in that aforementioned dimension.

[shadow65]

There have been reports of the newer BDM mags cracking feed lips. Could be the new mixture of polymer/nylon. I too would be very careful trimming the feed tower.

[Bongos]

All ten round BD mags are like that. It's not even filing off, it's more like polishing. You just have to remove less than 1/4 of millimeter. It doesn't affect mag in any way. Regular size mags a drop free out of the box.

+1 this is the correct way to do it