Ideal Handbook No. 17, published in 1906, shows a new cast bullet innovation ....the "gas check cup" along 2 new molds designed to use them that are still with us today.... #308284(now Lyman's 311284) for the .30-40 Krag and the#308291 (now Lyman's 311291) for the .30-30. Three other molds were also introduced...321247 for the .32 W.S.; 321295 for the .32-40 & 375296 for the .38-55, but they have since been obsoleted.
But what event lead up to the research and development of this new cast bullet device? A hint of that was noted in Ideal's 1904 manual. Dr. Walter G. Hudson, who was a World Champion Rifle shooter and held many records in his day, had been working on the problem of trying to achieve 1,500 f.p.s. in the .30 U.S. Army (.30-40) with 200+ grain bullets which was felt would give accurate shooting at 600 yards.
Dr./Cpt. Walter Guy Hudson was perhaps the leading Krag shooter in the history of the competition Krag. He was a firing member of the 1902 Palma team, came in second in the Wimbeldon Cup a couple of times, and generally regarded as a champion class rifle competitor, not only with the Schuetzen rifle, but with the military rifle.
Beginning in 1901, there was a desperate need for military practice ammunition that was accurate to the mid ranges (600 yards) and Hudson applied himself to the task of perfecting a lead bullet load that would perform out to this range.
The problem he encountered in trying to achieve that goal was fusion, or gas cutting as we know it today. He tried experimenting with antimonial alloys for stronger bullets but fusion persisted. He worked with J.H. Barlow of Ideal on bullet design and diameters, even to the point of using a front "gas check" band (front driving band) diameter of .325"(!) but to no avail.
Eventually, Dr. Hudson and Mr. Barlow of Ideal Manufacturing Co. hit upon the idea that a copper alloy spacer to insulate the bullet from the hot powder gases might work. They tried copper discs under plain based bullets, and found that they successfully prevented fusion. Higher velocities were then achieved with no leading. . Further development lead to the cup profile and the first gas checked bullet... Ideal's #308284.
Since the gas checked #308284 worked very well, Mr. Barlow set to work to develop additional gas checked bullets very quickly. #308291 for the .30-30 was next. Samples of cartridges loaded to factory velocities with the new bullet designs were sent to the Marlin Firearms Co. and Savage Arms Company for their evaluation.
Marlin responded ‚€œWe have the pleasure of reporting to you that these appear to be in every way equal to factory loaded ammunition with metal jacketed bullets.‚€œ Savage wrote back that they tested them in the .30-30 and .303 Savage and they compared favorably in accuracy with their jacketed bullets.
A few years later, in 1909, the Ideal Handbook No. 19 illustrated a total of 15 different gas checked bullets in calibers ranging from the .25-20 up to .38-55.
It is known that these first gas checks were designed to fall from the base of the bullet shortly after leaving the muzzle. Some 60 or so years later, Hornady Manufacturing came along with a new crimp on engineered gas check designed to stay with the bullet in flight. And the rest shall we say‚€¶.is history.