Magazine ID

[bwnva]

I've come across these magazines. They appear to have a "Colt 9mm" cut on one side (but seems strange as they appear to be single feed) and a cut on the back of the magazine. Can anyone tell me what they were originally designed for and what you think the cut on the back is for??? Any idea of the value? Thanks, bwnva

 

[Tommyboy]

They were originally Madsen Model 50 mags that look like they’ve been modified with a notch in the back for use in a MAC M11/9. Not sure about the side cut though. Value is probably around $35 each. Unfortunately they will no longer work in the Madsen because the upper rear catch tab has been ground off.

 

[bwnva]

Tommyboy, thank you. I'll probably sell them as I don't have a use for them now.