19 years in the Royal Regiment of Canadian Artillery for me. Retired as a captain. M109s, C1, C3, C2, LG1s and M777s during my career.
Firing Tables usually are a big thick book with every charge (and depending on the specific howitzer, charge system) laid out for each of the projectiles that could be used with a weapon system for both high and low angle applications. What does that mean in layman's terms? Lots and lots of pages lol. Basically a pain in the ass to pack around with you. There were several methods to condense them to a more portable format and this is one of them. It covers one specific projectile only (
https://en.wikipedia.org/wiki/M107_projectile). Other than that it is just a slide rule presentation of tabled data like any other for charges 3-7 (literally bags filled with propellant) that we would fire and 1,2 and 8 which we never did (1 and 2 were wartime only due to the chances of a sticker, literally a charge low enough where the projectile may not exit the barrel, and 8 was a rare overcharge that was a one piece charge we never used due to expense, barrel life, and lack of ranges long enough to use them in).
I guess I didn't answer the question hahahaha. Yes, I could theoretically use it and I could certainly teach you MAPS (Manual Artillery Plotting Systems - IE solving the indirect fire problem without the use of a computer with IFCCS) but I'm sure no one has enough time or interest for that lol. It is a cool piece of artillery data and memorabilia for sure.