Suppressed .510 Whisper
Thompson Center Single Shot Break-Action
Homemade (Form 1) Silencer
750gr Hornady AMAX ~950FPS
The .510 Whisper is a .416 Rigby (or .338 Lapua) case that has been shortened and necked to receive .50BMG bullets. Think .300 Blackout (whisper) (also basically an SSK design but updated and SAAMI registered) and now 8.6 Blackout but on COCAINE.
This is an extremely old video from my extinct "uswg01" channel.