What would they be using?

[trajectory]

They look like bolt action/ top lever cocking magazine fed bb rifles, 310 Haenels or Anchutz 275 to me, but that's just my opinion after a quick look.

[Mach 1.5]

Anschutz 275. Mach 1.5

[Epicyclic]

They look very serious here, but Floyd enjoyed a bit of 'larking about' too....See them in '67 on Y*utube cavorting in a park playing air drums and so on to their hit song 'See Emily Play'.

[rapidresponse1]

as mick says

[45flint]

[T 20]

I was once offered three of these for £5 but I turned them down as they took oddball sized bbs.