I make and shoot gas check cast boolits in rifles. A few months ago I purchased a reprint of the No. 26 "The Ideal 1915 Hand Book". This is a really great little book and is evidently the first year of gas-check bullets. I was amazed to see the Lyman 311284, 311329, and 311299. Besides these there are several 7mm bullets listed;285346 and 285377(my favorite). There is lots of reloading data for a number of powders I had never heard of, but there are a few listings for Unique.
This old reprinted manual comes to you courtesy of Cornell Publications. I also have the No.34 handbook which covers years 1940-1947. These are a great buy and really good reading!.................