American & British 410 Shotguns. Ronald Gabriel
than a “misbegotten” gauge reserved for the taxidermist or small kids.
A recent ballistic assessment for the modern 410 loads proves very reassuring for the game shooter [13]. The striking energies of 6- and 7-shot 410-gauge cartridges at velocities of 800 and 900 ft/s at 25 yards are over the 1 ft/lb of minimum energy necessary to effectively kill small wing and ground game. At maximum powder loads, a 3-inch 11/16-ounce 410 cartridge of shot sizes 5 through 9 has a muzzle velocity of 1135 ft/s, slower than any gauge from 12 to 28, but sufficient for an effective kill.
This compares favorably with Askins’ original data. The 2-inch cartridge contains 3/8-ounce shot and is effective up to 20 yards with a pattern density of 80 to 90 percent. The 2 1/2-inch shell with 1/2-ounce shot is effective up to 25 yards with a density of 80 percent. The 3-inch shell with 3/4-ounce shot is effective up to 30 to 35 yards with a density of over 90 percent. The pellet count at 30 to 35 yards in a 30-inch circle for the 3-inch 410 cartridge is superior to the shorter shells at shorter ranges.
Short of wild pheasant, big duck, and geese, the 3-inch cartridge is effective in the hands of a good shooter for all wing game under 30 to 35 yards. Recent essays on self-loading the 410 cartridge illustrates the many variables in producing a custom load [14,15].
Chris Cradock, once the grand man of British clay target shooting, started shooting with a 410 as a 10-year-old boy [16]. Despite the obvious advantages for a beginner—small size, small recoil, small price—he couldn’t refrain from recalling that “not for nothing do our American cousins dub these guns the ‘idiot sticks’” [17]. He is certainly referring to earlier American shotgun writing by big bore aficionados such as Askins, Keith, and O’Connor.
Commentary
This is fair enough when we consider that for upland game shooting in the wide-open American West—“rough shooting” not dreamt of in Britain or Europe—long-range accuracy is at a premium. Anyone who has hunted wild chukar among the rocky outcrops and mesas in the California and Nevada high deserts, offering but a small handful of shooting opportunities over a long and hard day of trekking up, down, and around inhospitable terrain, will so attest. All who have tried to walk or run down the wild ruffled grouse in the broad undulating plains of South Dakota will quickly agree that big bore shotgunning, especially for meat or survival hunters, will always dominate certain shooting or hunting venues.
Nothing could be more inappropriate than a 410 bore for large wild upland wing game or for smaller game that flushes at 30 or more yards. It is equally inappropriate for waterfowl, pass, or decoy shooting at almost any range. Greener acknowledged that for the naturalist, the taxidermist, and the gamekeeper, the 410 was in demand because of its portability and stock detachment but that “its killing range” was up to only 25 yards.
Shooting instructors dislike teaching a beginner with the 410, especially if the 2-inch cartridge with 3/8-ounce shot is used. This yields a meager number of pellets, and because many guns were full choked, a pattern “like thrown by a rifle bullet” occurs. This results in many more missed than hit targets, a demoralizing experience for a novice. This also raises the issue of how does the choke affect 410 ballistics.
Photo 3: A typical very effective pattern of a cylinder-choked 410. Photo courtesy of Shotgun Digest, 4th Edition, 1993.
The Effects of Choke
Choke boring was patented in England by W.R. Pape in 1866 but may have been developed earlier by Fred Kimble of Illinois [11]. Greener brought it to its first commercial success in the 1870s by holding a number of clinics and trials to demonstrate its value [6].
Choke is defined as the amount of constriction at the barrel muzzle in thousandths of an inch. It is generally accepted that 40 thousandths is full choke, no constriction is true cylinder.
Although it is demonstrable that the degree of choke is relatively unimportant in determining pattern density under 15 yards, in the 15 to 35 yard range, choke becomes increasingly important. Moreover, there is considerable controversy as to what choke is appropriate for game shooting.
This writer, a 410 shooter all of his life, argues that a full choke reduces the number of cripples; hence lost birds. This is especially true with wild Valley and Gambel’s quail in California, Gambel’s and Scale quail in Arizona, Scale in Texas, and the three major quail species in Mexico. The problem of crippled “runners” is nearly insoluble without dogs, and much western quail hunting is done without our canine companions.
This is less a problem for snipe, woodcock, mourning dove, or whitewing dove shooting. They are not “runners” and a cripple can usually be retrieved with or without dogs. Southeastern bobwhite hunting in America is always done with dogs, and “runners,” therefore, are not a problem. With retrieval dogs, wing game can be shot with a more open choke, improving the kill-to-cartridge ratio without a significant loss of crippled birds.
A recent essay in Shotgun Digest presents a powerful argument for a straight cylinder choke when hunting in thick woodcock and quail coverts where shotgunning is fast and close [18]. At 15 yards, the 3-inch 11/16-ounce load 410 cartridge with the cylinder choke will open more uniformly, faster, and wider than any other choke and gauge duo does. Photo 3 illustrates pattern uniformity and density at 15 yards with a cylinder 410 cartridge.
Furthermore, based upon Askins’ pounds of energy per pellet, only two or three 8 or 7-1/2 shot will take down any small game bird. Modern powder will propel the shot at over 1100 ft/s.
The essay does agree that rabbit, squirrel, and pass shooting for high dove requires a more restricted choke, notwithstanding the problems of a long shot string and shot deformation with patchy perimeter pellet hits.
Cradock points out that a full choke is problematic for even an experienced shot. At 25 yards, in all bores 12 through 410, the full choke shot pattern has a diameter of 21 inches (340 square inch area). At 25 yards, the improved cylinder choke in the 410 bore has a shot pattern diameter of 32 inches (800 square inch area). This latter choke is a more practical choice for some small wing and ground game species. There is still sufficient pellet density to kill, depending upon cartridge length and range [17].
A recent paper has recommended full-length plastic wads and slow burning powder giving an approximate velocity of 1200 ft/s of hard quality shot [19].
Physics
There is a well-known and interesting characteristic about the 3-inch 410 cartridge that results in its being called a “ballistic abortion” [13]. This is because this cartridge has the longest shot “string” or “column” of all cartridges in all bores, due to the soft lead shot and to a poor velocity-to-pressure ratio.
For example, the 410 shot column (the amount of shot deformed by contacts with the cone of the choke) is 2.175 inches long, compared with the 12 bore at .69 inch and 28 bore at 1.21 inches. This “rifle bullet” or “balling of the shot” effect results from the deformation of pellets and may throw the charge out to 100 to 150 yards. In general, the smaller the gauge, the longer the column and the less dense the pattern.
This was first described by Burrard in 1888 [20]