After a brief Google search, I still have no idea what a Sure Grip Trigger Lock is. Context/back story would help.
If your gun discharges while inserting a magazine, send it back to the manufacturer or a gunsmith. There is something seriously wrong.
MSgt, USAF, Retired
NRA Life Member
The hardest thing to explain is the glaringly evident which everybody had decided not to see. - Ayn Rand