RCBS Uniflow Powder Measure - Large or Small Drum?

[Dave8532]

How can I tell if I have the small or large drum on my old (circa 1970) powder measure?

 

[Mooseknuckles]

Pull the drum, the powder side of the drum on a small will be 1/2 inch, a large drum will be around 3/4.
RCBS tech support
Small = .5000
Large = .6875

 

[Dave8532]

Appreciate that Mooseknuckles!