High Velocity/Low Pressure/Black Powder vs Smokeless Powder...the confusion...1902

Western Field The Sportsman's Magazine of the West · Volume 1 Another great explanation from 1902. Not only is this nearly ten years after the introduction of smokeless powder, it is also the beginning of the new "High Velocity" fad that, as well as smokeless powder itself, many misunderstand even today.

Below are two examples of misunderstanding what is safe, and what is not safe for your particular black powder firearm. By 1905, Smokeless Powders were divided in two classes, low and high pressure. The first named being mostly used in old black powder cartridges the latter for cartridges of the military type. Aside from black powder; most just getting over the fact that the new smokeless powder was also divided into two classes, "bulk for bulk" and "dense", both equaling the strength of a black powder charge but one being bulk for bulk, and one being much less than bulk....but yet both safe for black powder firearms. Generally for rifles, anything larger than .32 cal. was basically a bulk for bulk while anything smaller than a .32 cal. was a less bulk for bulk, or what was called "dense". Aside from shooting jacketed bullets and large quantities of smokeless shots fired in the soft steel barrels, smokeless powder was plenty safe for use in black powder arms. The concerns below involve high pressure vs low pressure and the confusion thereof. Thus, by early 1900's definitions, we must divide these pressures into at least two groups.

Smokeless Powder Pressure Classes;

• Low Pressure - anything below, say...30,000cup
• High Pressure - anything above, say...30,000cup

Just because it may say low pressure doesn't mean it is safe for the weaker barrels...but at the same time, smokeless powder itself is not unsafe to use in soft steel BP barrels either.

Then further down the book we find this High Velocity/Low Pressure data while speaking about special sights...

"These cartridges are especially designed for use in rifles originally built to use black powder only." 

With that said, there is why we need to understand what is meant by High Pressure vs Low Pressure, regardless of high velocity or low velocity....as well as...the reason for the switch from soft steel to special steel.

Also, keep in mind that even though this 1902 information is nearly ten years into using smokeless powder, the High Velocity-Low Pressure is a another new Nomenclature!