I used a Lee powder thrower, never had an issue with repeatability.

These days I've ditched the phials and use a dedicated dispenser. Derek at Anvil Conversions does them. I already owned one of Derek's Remington .44 nitro conversions and the dispenser for than gun worked very well so I ordered a second dispenser for the Alfa. Not cheap but they certainly work and are much more convenient than the phials.

Details on his page http://anvilconversions.co.uk/

Cheers!
Paul.