Gwinn Bushmaster Arm Pistol Failure points

[Fourfiftyfourcasull]

Recently i acquired a collection that included one arm pistol and a barreled action with the mag well attached. Upon further inspection, I discovered that the trigger group had been cracked along the mag release. I cannot imagine what would have caused this damage, on what i assume is a low stress component?

Just wondering if this was a common issue or what kind of reputation these guns had?

Best, 

Mike 

Edited February 22 by Fourfiftyfourcasull

[MPFiveO]

That looks like the result of a Kaboom. Looks like the catch itself is broken off too. I had one of those years ago and the nub on top of the trigger cracked where the transfer bar made contact with it. That was the only weak point I found with it. I currently have an original Gwinn made Arm Pistol. It's a well made piece. The upper receiver is milled aluminum rather than stamped sheet metal like the Bushmaster version.

[All Here]

I have an owned a few of these over the years and never saw this issue before.  Not sure what happened there.

[GUNBUGS]

Had 2 Gwinn semi-autos years ago. Both broke the tip of the sear extension that connected to the trigger bar repeatedly. (Sticks up out of the lower). The real fun came when one broke the disconnector when firing and went full auto. THAT was unexpected. But briefly entertaining. Fun times. Looks like your gun had a case head failure or out of battery detonation. Leaked gas and blew the mag out and stressed the lower with gas or by forcing the mag out.