Green’s Dictionary of Slang

an eccentric, esp. a particularly violent one.

1962		B. McGhee Cut and Run (1963) 111: The sentence might have been lighter [...] if his defending officer hadn’t been such a ‘bampot’.
1973		(con. mid-1960s) J. Patrick Glasgow Gang Observed 53: James fuckin’ Patrick, ya bam-pot ye.
1989		J. Morton Lowspeak 19: Bam-pot – a fool [...] now come to mean a dangerous and violent person of unstable mental condition.
1999		A. O’Hagan Our Fathers 253: Cunts waving their arms about the place. Big noises. Bampots the fucking lot.
2003		C. Brookmyre One Fine Day in the Middle of the Night 50: Davie Fuckin’ Murdoch [...] Sociopath, psychopath, whatever you like, Matt had always preferred bampot.
2012		(con. 1980s) I. Welsh Skagboys 193: Two dodgy bamsticks oot ay circulation through the jail and hozzy gigs.
2015		Guardian 15 Aug. 🌐 Other countries got debonair bampots [...] the poor North Koreans got a wee bloke whom you imagine Chucky the demonic doll to look like.
2018		Observer 15 July 3/4: You radge orange bampot! Tens of thousands of Scots take to the streets [...] condeming Donald trump’s policies.
2021		L. McInerney Rules of Revelation 172: She thought I was always a bampot and she was OK with it.