I do not know all the particulars on it but in an American Rifleman article on smokeless powders which first appeared in the 1950s & was then reprinted in their Reloaders Guide in the 60s as I recall, it was stated that Infallible & Unique were the same powder. I do know that on the Lyman 55 powder measure the same settings were listed for the same weight charge. Also early Lyman data lists only Infallible for shot shells & only Unique for pistols & reduced rifle loads.
The oldest data I have which lists pressures is A Herter's "Professional" Reloading Data book. Pressures are crusher pressures as they show a picture of the pressure gun & describe how they are taken, though all are given as "PSI".
One chart is for paper cases & paper wads.
25grs Unique under 1Ľoz shot for a 3 3/4DE gave 9,489.
23grs Unique under 1 1/8oz for a 3DE gave 8,725
23grs Red Dot under 1 1/8oz for 3DE gave 10,178
20grs Red Dot under 1 1/8oz for a 2 3/4DE gave 9,462
A 3 dram measure of DuPont Bulk Shotgun Smokeless under 1 1/8oz gave 10,500
I also have an original 12ga Lee Loader with the instruction manual having a 1961 copyright date. In it they state that because of the strength of "Modern" primers DuPont Bulk should no longer be loaded in equal measure to Black Powder. For loading the bulk they recommend using the shot measure set to 1 1/8oz for loads of either 1 1/8oz or 1Ľoz. They also show lighter loads wirth 1 1/8oz with the shot measure set at either 1oz or 7/8oz. On their charge table they show these loads as having about a 25% greater DE than they would actually measure in drams of black. No pressures are listed in the Lee loads though. They do show the same 23grs Redot with 1 1/8oz as the standard 12ga load.
Note Well!! all these loads ar around 50 Years old & ""ARE NOT"" recommended for current loading Data, but given only for historic interest.
