7-30 Waters
Encyclopedia
The 7-30 Waters cartridge is a wildcat cartridge
developed by author Ken Waters in 1976 to give better performance to lever action rifle shooters than the parent .30-30 Winchester
cartridge, by providing a higher velocity and flatter trajectory with a smaller, lighter bullet. By 1984, Winchester
introduced a Model 94 rifle chambered for the 7-30 Waters, establishing it as a commercial cartridge. In 1986, Thompson/Center began chambering 10", 14" and 20" Contender barrels for the cartridge.
case necked down to 7mm), provides the answer.
There are two primary reasons a 7mm recoils less than an comparably effective .30 cal. cartridge: (1) to match the 7mm's ballistic coefficient requires a significantly heavier .30 cal bullet; and (2) to drive that heavier .30 cal bullet at similar velocities (for kinetic energy and wind resistance ("time-to-target")), requires more powder. This combination of heavier bullets with heavier powder charges significantly increases the recoil of the .30 caliber.
The .30-30 Winchester is typically limited to short ranges, primarily because of the relatively small case capacity and the 150 grain and 170 grain bullet weights. To compensate for this, Waters necked the cartridge down to use a 7mm bullet (.284 inches), rather than the original .308 caliber (7.62 mm) bullet. Because it was designed to function in lever action rifles, the 7-30 maintained the same low working pressure, but was able to fire bullets of lighter weight at higher velocity. A typical .30-30 factory load fires a 150 grain bullet at 2390 f/s, while the Federal Premium
Vital-Shok 7-30 factory load fires a 120 grain Sierra
GameKing bullet at 2700 f/s. Muzzle energy is just over 1900 ft-lbs for both loads, but the lighter weight bullet with higher velocity has a flatter trajectory.
As of November 2011, Hornady Manufacturing Company does not offer either 7-30 Waters LEVERevolution ammunition or 7mm/.284" FTX bullets. These would allow the safe use of pointed, ballistically efficient
spitzer bullets in 7-30 lever action rifles' tubular magazines.
Thompson Center Arms
began to chamber the 7-30 Waters in their Contender single shot pistol starting in 1986. Factory loads are capable of velocities of 2400 f/s from the 14" pistol barrel, making the 7-30 Waters one of the fastest commercial rounds available for the pistol. In addition, the single shot Contender can safely use pointed bullets, which allows the handloader
to gain additional retained velocity at long ranges for uses such as metallic silhouette
shooting.
Where the 7-30 has gained a strong foothold is in handguns. In the field of handgun metallic silhouette shooting, a suitably loaded 7-30 Waters provides performance equal to other 7mm wildcats, such as the 7mm International Rimmed, but without the work of forming cases. It also adds the bonus of being able to shoot commercial ammunition, with some performance loss.
Wildcat cartridge
A wildcat cartridge, or wildcat, is a custom cartridge for which ammunition and firearms are not mass produced. These cartridges are often created in order to optimize a certain performance characteristic of an existing commercial cartridge.Developing and using wildcat cartridges does not...
developed by author Ken Waters in 1976 to give better performance to lever action rifle shooters than the parent .30-30 Winchester
.30-30 Winchester
The .30-30 Winchester/.30 Winchester Center Fire/7.62×51mmR cartridge was first marketed in early 1895 for the Winchester Model 1894 lever-action rifle. The .30-30 , as it is most commonly known, was the USA's first small-bore, sporting rifle cartridge designed for smokeless powder. The .30-30 is...
cartridge, by providing a higher velocity and flatter trajectory with a smaller, lighter bullet. By 1984, Winchester
Winchester Repeating Arms Company
The Winchester Repeating Arms Company was a prominent American maker of repeating firearms, located in New Haven, Connecticut. The Winchester brand is today used under license by two subsidiaries of the Herstal Group, Fabrique Nationale of Belgium and the Browning Arms Company of Morgan, Utah.-...
introduced a Model 94 rifle chambered for the 7-30 Waters, establishing it as a commercial cartridge. In 1986, Thompson/Center began chambering 10", 14" and 20" Contender barrels for the cartridge.
Development
Why neck down a .30 cal. cartridge to 7mm? This quote from a review of the 7-08 Rem. (a .308 Win..308 Winchester
The .308 Winchester is a rifle cartridge and is the commercial cartridge upon which the military 7.62x51mm NATO centerfire cartridge is based. The .308 Winchester was introduced in 1952, two years prior to the NATO adoption of the 7.62x51mm NATO T65...
case necked down to 7mm), provides the answer.
There are two primary reasons a 7mm recoils less than an comparably effective .30 cal. cartridge: (1) to match the 7mm's ballistic coefficient requires a significantly heavier .30 cal bullet; and (2) to drive that heavier .30 cal bullet at similar velocities (for kinetic energy and wind resistance ("time-to-target")), requires more powder. This combination of heavier bullets with heavier powder charges significantly increases the recoil of the .30 caliber.
The .30-30 Winchester is typically limited to short ranges, primarily because of the relatively small case capacity and the 150 grain and 170 grain bullet weights. To compensate for this, Waters necked the cartridge down to use a 7mm bullet (.284 inches), rather than the original .308 caliber (7.62 mm) bullet. Because it was designed to function in lever action rifles, the 7-30 maintained the same low working pressure, but was able to fire bullets of lighter weight at higher velocity. A typical .30-30 factory load fires a 150 grain bullet at 2390 f/s, while the Federal Premium
Federal Cartridge
Federal Cartridge is a wholly owned subsidiary of Alliant Techsystems, located in Edina, Minnesota. With a work force of nearly 1,000 in Anoka, Minnesota, Federal manufactures a complete line of shotshell, centerfire, and rimfire ammunition and components....
Vital-Shok 7-30 factory load fires a 120 grain Sierra
Sierra Bullets
Founded in 1947 in California, Sierra Bullets is an American manufacturer of bullets intended for firearms. Based in Sedalia, Missouri since 1990, Sierra manufactures a very wide range of bullets for both rifles and pistols. Sierra bullets are used for precision target shooting, hunting and defense...
GameKing bullet at 2700 f/s. Muzzle energy is just over 1900 ft-lbs for both loads, but the lighter weight bullet with higher velocity has a flatter trajectory.
As of November 2011, Hornady Manufacturing Company does not offer either 7-30 Waters LEVERevolution ammunition or 7mm/.284" FTX bullets. These would allow the safe use of pointed, ballistically efficient
External ballistics
External ballistics is the part of the science of ballistics that deals with the behaviour of a non-powered projectile in flight. External ballistics is frequently associated with firearms, and deals with the behaviour of the bullet after it exits the barrel and before it hits the target.-Forces...
spitzer bullets in 7-30 lever action rifles' tubular magazines.
Commercial adoption
By 1982, Waters had perfected his new cartridge, firing a 139 grain flat point bullet at a muzzle velocity of 2600 f/s from a lever action rifle with a 24" barrel. By 1983, he had managed to attract the attention of Winchester, which led to the introduction of the Model 94XTR angle eject rifle and carbine in the new caliber the next year. "[T]he 7-30 Waters cartridge, with its flatter trajectory and higher velocity, have made [the Model 94] what many consider to be an ideal mountain rifle: lightweight, but capable of reaching out for the longer shots."Thompson Center Arms
Thompson Center Arms
Thompson/Center Arms Company is an American firearms company based in Rochester, New Hampshire. The company is best known for its line of interchangeable barrel single-shot pistols and rifles. Thompson Center manufactures muzzleloading rifles and is credited with creating the resurgence of their...
began to chamber the 7-30 Waters in their Contender single shot pistol starting in 1986. Factory loads are capable of velocities of 2400 f/s from the 14" pistol barrel, making the 7-30 Waters one of the fastest commercial rounds available for the pistol. In addition, the single shot Contender can safely use pointed bullets, which allows the handloader
Handloading
Handloading or reloading is the process of loading firearm cartridges or shotgun shells by assembling the individual components , rather than purchasing completely assembled, factory-loaded cartridges...
to gain additional retained velocity at long ranges for uses such as metallic silhouette
Metallic silhouette
Metallic silhouette shooting is a group of target shooting disciplines that involves shooting at metal cutouts representing game animals at varying distances. Metallic silhouette shooting can be done with airguns, black powder firearms, modern handguns, or modern rifles...
shooting.
Use
The 7-30 is suitable for hunting game up to and including deer sized animals, and with heavier bullets, black bear. Best performance is had with the rifle barrel; with the shorter carbine barrels the .30-30 is a better choice. With the long barrel, however, the 7-30 provides flatter trajectory, and a longer effective range, as well as reduced recoil from the lighter bullets. Despite the advantages, the 7-30 still lags far behind the venerable .30-30 in popularity, however. Paco Kelly, of leverguns.com, wrote this about the 7-30: "I like the model 94 Winchesters....and the 7 Waters fits the standard 94 action very well. It is exactly what it was designed for...a light, handy, and fairly powerful round and rifle for deer and black bear."Where the 7-30 has gained a strong foothold is in handguns. In the field of handgun metallic silhouette shooting, a suitably loaded 7-30 Waters provides performance equal to other 7mm wildcats, such as the 7mm International Rimmed, but without the work of forming cases. It also adds the bonus of being able to shoot commercial ammunition, with some performance loss.