.458 Winchester Magnum - Ammunition

Ammunition

Since the .458 Winchester Magnum was intended as a dangerous game hunting cartridge, almost all ammunition manufactured for the cartridge is manufactured for these game species. Bullets used to load the .458 Winchester Magnum by ammunition manufacturers generally range between 450–510 gr (29–33 g).

Winchester currently offers ammunition in the traditional 510 gr (33 g) Soft Point and the new 500 gr (32 g) Nosler Partition and Nosler Solid. The Winchester 500 gr (32 g) loading has a muzzle velocity of 2,240 ft/s (680 m/s) and muzzle energy of 5,570 foot-pounds force (7,550 J). Winchester's 510 gr (33 g) X4581 ammunition, which has a muzzle velocity of 2,040 ft/s (620 m/s), is rated for CXP3 (large, non-dangerous) game species.

Hornady offers what they call a "heavy magnum" loading that features a 500 gr (32 g) bullet with a velocity of approx 2,260 ft/s (690 m/s). They use a special double-based cooler burning propellant ("powder") not available to the public for handloading. This innovative loading allows the .458 Winchester Magnum to attain 5,670 foot-pounds force (7,690 J) of muzzle energy. Federal Cartridge is now loading a 500-grain (32 g) Barnes X bullet with a sectional density and ballistic coefficient that allows it to maintain approximately 2,000 foot-pounds force (2,700 J) of energy at 500 yards (460 m) and a flatter trajectory than has ever before been attained with this cartridge and bullet weight. Numerous companies offer rifles in this caliber, including the Winchester Model 70, which was used by Clint Eastwood in Dirty Harry.

The rounds for the .458 Win mag are more expensive than cartridges like the popular .30-06, making handloading a worthwhile effort. Though more expensive than deer hunting ammunition, the .458 Winchester Magnum is significantly less expensive than its competitors. For many decades the .458 has been the most popular rifle cartridge of professional hunters who pursue heavy dangerous game in Africa because of its performance, price, and availability. When British ammunition companies, including Kynoch, began closing in the 1960s, Winchester and the .458 Winchester Magnum filled the gap left behind.

The recoil of the factory loads is about 70 foot pounds. Handloads can make this cartridge more comfortable to shoot, for example using a 300-grain (19 g) cast lead bullet at 1,282 ft/s (391 m/s). This load mimics the .45/70 in both power and recoil.

.458 Winchester Magnum Ammunition

Ammunition	Bullet	Muzzle Velocity	Muzzle Energy	MPBR/Zero	Notes
Winchester X4581	Winchester 510 gr (33 g) SP	2,040 ft/s (620 m/s)	4,712 ft·lbf (6,389 J)	195 yd (178 m)/167 yd (153 m)	Currently in production
Winchester S458WSLSP	Nosler 500 gr (32 g) Partition	2,240 ft/s (680 m/s)	5,570 ft·lbf (7,550 J)	218 yd (199 m)/185 yd (169 m)	Currently in production
Winchester S458WSLS	Nosler 500 gr (32 g) Solid	2,240 ft/s (680 m/s)	5,570 ft·lbf (7,550 J)	213 yd (195 m)/181 yd (166 m)	Currently in production
Federal P458T1	TBBC 400 gr (26 g) SP	2,250 ft/s (690 m/s)	4,496 ft·lbf (6,096 J)	212 yd (194 m)/180 yd (160 m)	Currently in production
Federal P458T2	TBBC 500 gr (32 g) SP	2,090 ft/s (640 m/s)	4,849 ft·lbf (6,574 J)	206 yd (188 m)/175 yd (160 m)	Currently in production
Federal P458T3	TBSS 500 gr (32 g) Solid	1,950 ft/s (590 m/s)	4,221 ft·lbf (5,723 J)	194 yd (177 m)/165 yd (151 m)	Currently in production
Federal P458D	Barnes 500 gr (32 g) TSX	2,050 ft/s (620 m/s)	4,665 ft·lbf (6,325 J)	206 yd (188 m)/175 yd (160 m)	Currently in production
Federal P458E	Barnes 500 gr (32 g) BS	2,050 ft/s (620 m/s)	4,665 ft·lbf (6,325 J)	205 yd (187 m)/174 yd (159 m)	Currently in production
Federal P458SA	Swift 500 gr (32 g) A Frame	2,090 ft/s (640 m/s)	4,849 ft·lbf (6,574 J)	207 yd (189 m)/176 yd (161 m)	Currently in production
Norma 20111102	Barnes 500 gr (32 g) BS	2,067 ft/s (630 m/s)	4,745 ft·lbf (6,433 J)	207 yd (189 m)/176 yd (161 m)	Currently in production
Norma 20111202	Swift 500 gr (32 g) A Frame	2,116 ft/s (645 m/s)	4,972 ft·lbf (6,741 J)	209 yd (191 m)/178 yd (163 m)	Currently in production