Hey All,

Went to the range the other day to finally test my DB Alloy build. Before I ever got to the shooting phase, I had issues with the printed Sten mags, so I decided to buy a few surplus mags from Atlantic Firearms. So I got my mags, polished them up, put a little lube around the follower and what not. The mags work fine outside the gun itself.

Got to the range, loaded up my mags, and when I pulled the charging handle, it seems like it is double feeding. The bolt charges two bullets instead of the one. Whatever, tried another mag, same thing. I’m thinking this is on the mags.

Any suggestions?

  • pepesilviaEnglish
    1·
    7 days ago

    I had this same issue and haven’t figured it out. I’m thinking of maybe modifying the tab to have the mags sit a hair deeper into the lower. What upper are you using? I’m using the left side charging Masterpiece arms upper.

  • KopsisEnglish
    1·
    8 days ago

    The printed mags usually feed more reliably (when new) than surplus. The problem with the printed mags is that the feed lips are really thin so you have to print with a stiff low-creep material (PET-CF works well). Even then they wear quickly.

    With surplus mags you’ll need to verify the feed lip geometry (they’re often bent/stretched) and you will probably have to tune the location of the mag catch adapter.

  • The ShittinatorMAEnglish
    1·
    8 days ago

    Metal surplus Sten mags? You printed the adapter for them, yeah?

    And can you replicate the issue at home with snap caps?

    • DinnerEnjoyerOPEnglish
      2·
      7 days ago

      Yes I have printed the adapters.

      Have not yet tried with snap caps as I have none in 9mm but will test soon.