saltpeter

[TomHorner]

where can I buy saltpeter in the uk?

[mikewith]

A very useful answer to this from bhvma: "Technically 'saltpeter' is potassium nitrate. It's typically available in reagent grade from a pharmacy, but will be expensive because of its purity, and controlled because it is potentially dangerous. Depending on your need, a much cheaper equivalent might be ammonium nitrate, a common fertilizer available at a farm supply outlet. Sodium nitrate could also be useful, from the same outlet.