.221 Remington Fireball

.221 Remington Fireball
L-R: 40 gr Hornady V-Max, 55 gr Sierra BlitzKing, .221 Remington Fireball, .22 LR Remington Golden Bullet
Type	Pistol / Rifle
Place of origin	United States
Production history
Designer	Remington / Wayne Leek
Manufacturer	Remington
Produced	1963
Specifications
Parent case	.222 Remington
Bullet diameter	.224 in (5.7 mm)
Neck diameter	.253 in (6.4 mm)
Shoulder diameter	.361 in (9.2 mm)
Base diameter	.376 in (9.6 mm)
Rim diameter	.378 in (9.6 mm)
Case length	1.400 in (35.6 mm)
Overall length	1.830 in (46.5 mm)
Rifling twist	1-12"
Primer type	Small rifle
Ballistic performance
Bullet mass/type Velocity Energy 45 gr (3 g) SP - Pistol 2,947 ft/s (898 m/s) 868 ft⋅lbf (1,177 J) 50 gr (3 g) SX - Pistol 2,813 ft/s (857 m/s) 879 ft⋅lbf (1,192 J) 55 gr (4 g) SBT - Pistol 2,700 ft/s (820 m/s) 891 ft⋅lbf (1,208 J) 45 gr (3 g) SP - Rifle 3,203 ft/s (976 m/s) 1,025 ft⋅lbf (1,390 J) 55 gr (4 g) SBT - Rifle 2,950 ft/s (900 m/s) 1,063 ft⋅lbf (1,441 J)
Test barrel length: 14", 24" Source(s): Accurate Powder

The .221 Remington Fireball was created by Remington Arms Company in 1963 for use in their single-shot bolt-action pistol called the XP-100. This was a special round designed for an experimental pistol, and has the highest velocity of any commercial pistol cartridge.

History

In the early 1960s Remington was working on an experimental bolt-action pistol based on their model 600 action. They wanted a highly accurate pistol that would be well suited for competition. After working with the .222 Remington they realized that it contained more powder than was necessary for the shorter barrels that are used even by specialty pistols. Typical rifle barrels range from approximately 18 to 26 in (46 to 66 cm), while typical pistol barrels range from 2 to 12 in (5.1 to 30.5 cm). Competition pistol sometimes have barrels as long as 16 in (41 cm), still making them shorter than the shortest rifle barrels.

The decision was made by Remington to base their new cartridge on a shortened version of the .222, optimized for their new XP-100 gun. The cartridge gained some popularity with silhouette shooters and varminters, but still takes a back seat to the more common .223 Remington.

Today the XP-100 is no longer in production. .221 shooters can still get Thompson Contender single-shot pistols chambered for the Fireball, and some rifle manufacturers are making guns for this cartridge as well. Like the .222 and .223, the .221 is well suited for the high-volume shooting for varmint hunting, having almost the same velocity and trajectory out to almost 300 yards (270 m).

Performance

SAAMI pressure levels are actually set higher for the .221 Remington Fireball at 52,000 C.U.P. than for the .222 Remington at 46,000 C.U.P. This was done in an effort to compensate for the shorter pistol-length barrels expected to be used. Because of this higher pressure, in a rifle length barrel the .221 is capable of velocities equal to that of the .222.

Offshoots

The .221 Fireball has been used by wildcatters to create a small efficient .17 caliber cartridge. The most common is the .17 Mach IV which is essentially the .221 necked down to the smaller caliber. This cartridge is reported to have a very flat trajectory and to be relatively quiet with low recoil. It has been so popular as a wildcat that in 2007 Remington legitimized it by introducing their own version only slightly different than the Mach IV and calling it the .17 Remington Fireball. A .20 caliber version is also gaining popularity called the .20 VarTarg (VT), "vartarg" being the combination of the words "varmint" and "target". The .221 Fireball has also been used as the base for the .300 Whisper, sometimes referred to as the .300/.221 or .300 Fireball. It is also the basis for other cartridges in J.D. Jones' Whisper family including the 6mm Whisper, which has been adopted by Knight's Armament Corporation for their new Knight's Armament Company PDW as the 6×35mm PDW.

See also

• List of rifle cartridges
• 5 mm caliber