Next generation Colt a bit of a rascal? (3,2,1,3)

I haven't cracked this one yet — but the brilliant team at Times for the Times have:

A cryptic hint with reference to the fire-arm manufacturer Samuel Colt precedes the main definition of the jocular American expression meaning a rogue or rascal. I associate it with the bewhiskered actor George ‘Gaby’ Hayes who appeared in many old Westerns on film and TV.