The Triggertech AR-15 Combat Trigger will work in that AR15 and can be used for those purposes.
The Triggertech AR-15 Combat Trigger will be compatible with any AR platform rifle that accepts standard AR trigger groups and 0.154" trigger pins.
The Triggertech AR-15 Combat Trigger will work with left handed rifles.
Christensen Arms uses Triggertech Triggers in most of their firearms. However, they do not specifically state what model of Triggertech Trigger is their CA9mm. I recommend contacting Christensen Arms for that information.
Yes, the Triggertech AR-15 Combat Trigger are designed as a drop in trigger for any mil-spec AR15 platform like the M&P 15. This trigger utilizes standard mil-spec trigger pins (0.154").
The Triggertech AR-15 Combat Trigger has a short, two-stage action, designed to feel like a 1911 trigger, that provides a true zero-creep break, extremely short overtravel, a sub 0.030” tactical reset and offers outstanding reliability.
The Triggertech AR-15 Combat Trigger should fit and function as intended in your Extar PCC as it is compatible with AR15 trigger parts.
Yes, this is compatible and will be a drop in trigger.
Yes, this should fit the Sig 516.