Help With US R161-72 Perf Question

So the attached were catalogued as R161-R172, which calls for rouletted 5 1/2. They however seem to be Hyphen Hole Perf 7 - I think - according to the description in the Scott catalog, " small rectangles of paper are cut out". But then again, I do not see the two 1/2 ¢ stamps listed as hypen hole - so are these mixed issues?? FWIW, I am not at all familiar with Hyphen hole examples, so I could be wrong all the way around....

Interestingly, the battleship documentary and proprietary stamps were the first series of revenue stamps that launched me into specializing. In those days the different methods of separation were simply listed together in the Scott U.S. Specialized and the National Album only contained space for a single set, thus encouraging the collecting of a mixed set as you have.

Because some of the battleship stamps with the rouletting only vertically or horizontally escaped the eyes of the Bureau of Engraving & Printing examiners before being sent to Internal Revenue and ultimately to the public, BEP switched to the hyphen hole perforations (removing a piece of paper). Interestingly, my mentor always preferred the older term "slot perforated" to the current "hyphen hole" perforated.

A little hard to see on the background of your album page. However, R161 only exists roulette 5 1/2. Your R163 and 164 are definitely hyphen hole 7. On these latter two see how the teeth are closer together. These help differentiate the two types of separation. Hope this helps.

Thank you. Here is a little better scan I hope - guess this is a mixed set... I can use the two 1/2¢ as a reference as to which are rouletted or not?

Since one is 5.5 and the other is 7, it should not be difficult to tell them apart, just use a perf gauge.

Oops, snafu... One gauge I have only goes to 8 and the unisafe to 7... Might have to look for an online one. Rats.

Your gauge is just fine, use the lines for double the rate, use 11 for 5.5, and use 14 for 7.
Or ingore the gauge and use a stamp of known rate to compare against the others.

Thanks !

So if I've measure correctly, the 1,2,4 & .50¢ are Perf 7 and the rest are 5 1/2 .