577 Tyrannosaur
577 Tyrannosaur
Type Rifle
Place of origin 22x20px United States
Production history
Designed 1993
Parent case New Design
Case type Rimless, Bottleneck
Bullet diameter 0.585 in (Bad rounding hereScript error mm)
Neck diameter 0.6135 in (Bad rounding hereScript error mm)
Shoulder diameter 0.673 in (Bad rounding hereScript error mm)
Base diameter 0.688 in (Bad rounding hereScript error mm)
Rim diameter 0.688 in (Bad rounding hereScript error mm)
Rim thickness 0.063 in (Bad rounding hereScript error mm)
Case length 2.990 in (Bad rounding hereScript error mm)
Overall length 3.710 in (Bad rounding hereScript error mm)
Rifling twist 1 in 12 in (305 mm)
Primer type Large Rifle Magnum
Maximum pressure 65,000 psi (Bad rounding hereScript error MPa)
Ballistic performance
Bullet weight/type Velocity Energy
750 gr (Bad rounding hereScript error g) Monolithic Solid2,480 ft/s (Bad rounding hereScript error m/s)10,240 ft·lbf (Bad rounding hereScript error J)
Test barrel length: 26 in
Source(s): A-Square Any Shot You Want

The 577 Tyrannosaur or 577 T-Rex is a cartridge developed by A-Square in 1993 for professional guides that escort clients hunting dangerous game. The cartridge is designed for use in "stopping rifles": A rifle intended to stop the charge of dangerous game. The 577 contains a .585-inch (Bad rounding hereScript error mm) diameter 750-grain (Bad rounding hereScript error g) Monolithic Solid Projectile which when fired moves at 2,460 ft/s (Bad rounding hereScript error m/s) producing 10,180 foot-pounds force (Bad rounding hereScript error J) of muzzle energy.[1] The production model from A-square is based on their Hannibal rifle platform. This cartridge has the distinction of possessing the heaviest free recoil of all commercially available, shoulder-fired weapons, at 220 lbs into the shoulder with its heaviest solid of 750 grains. The larger caliber, .700 Nitro Express, drives a 1,000 grain solid at 8,900 foot-pounds, with free recoil of 200 lbs into the shoulder.


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External linksEdit

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