CCTV footage shows a murdered clutching a horseshoe that he used to later kill a golf greenkeeper by hitting him on the head.
Kirkpatrick Virgo, from Slough, hit Thomas Parker, 24, with the item after the pair argued over loud music from a speaker on a train on 30 July 2022.
The 42-year-old, from Slough, admitted manslaughter and carrying an offensive weapon, but denied murder.
A jury found Virgo guilty of murder on Wednesday, 29 March.