I use a lot of GT85 - on the various motor/pushbikes/garden tools. Prefer it to WD40, in fact. Fine for gears/chains, show no signs of rust/seizing, kept outside all year round. The garden tools get a heavy coat over winter. But have only ever used it to soak a seized piston on my guns. Think it's too thin/not durable for gun use.

ATB

Bru