Piston for G&P M870

Same idea behind this as the cylinder. These pistons have been known to have breakage problems where the trigger sear catches the piston. The idea is to ultimately have this made of aluminum to negate this issue. The one I had printed functions perfectly with a weak test spring; locks back and releases just like the stock part. Make sure to print this in something strong, the versatile plastic material from Shapeways was much too weak and couldn't handle the stock spring. Other than that it shou