'Spose you could always stop when you get to 60psi, and then pump it back up again, it'd save you a bit of time. But you'd still have to have a decent sized chamber on it.
@feral_patriot
Ah thanks, what did I do to deserve that?

Pressure tested a "Coffin" setup to 300 psi before minor leaks occurred.Unless you want a full galvanised metal cloud/vortex with 450psi running through it Shocked Smile