Comments by "GunFun ZS" (@GunFunZS) on "S&W 1940 Light Rifles: Receiver Breakage is a Problem" video.

  1. It seems obvious to me that the reason they shorten the bolt on the Mk 2 is to prevent direct impact on the threaded cap. what they could've done to fix it is that plus adding a bunch of mass around the front end of the bolt . I don't think there's anything actually occupying that space in the receiver so there's no reason it couldn't be a little bit thicker . No doubt the formulas weren't worked out yet . However mass is the critical feature. Spring rate is almost inconsequential . The usual wait for 9 mm is 1.5 pounds for the bolt.
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