5x replacement Prowin 170mm hi-capa mag lips.
Filled one of my mags today with BB's to chrono the new pistol and set it down on the table while I switched on the chrono and set it up. Was in the middle of the chrono settings when suddenly the mag vomitted the entire compliment of ammo across the room.
Checked the mag and everything seemed ok.
Only put 5 BB's in this time aaaaaand... Boom... Off flies one of the lips, completely sheered. Brilliant.
The other 5 mags seem ok so just ordered a handful to replace the broken one and have some spares in my box.
Fuck!