.458 Lott
.458 Lott | ||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
![]() .458 Lott, its parent case the .375 H&H Magnum and the .458 Winchester Magnum for comparison. | ||||||||||||||||||||||||
Type | Rifle | |||||||||||||||||||||||
Place of origin | ![]() | |||||||||||||||||||||||
Production history | ||||||||||||||||||||||||
Designer | Jack Lott | |||||||||||||||||||||||
Designed | 1971 | |||||||||||||||||||||||
Manufacturer | A-Square | |||||||||||||||||||||||
Produced | 1989 | |||||||||||||||||||||||
Variants | .450 Watts Magnum, .450 Ackley Magnum | |||||||||||||||||||||||
Specifications | ||||||||||||||||||||||||
Parent case | .375 H&H Magnum | |||||||||||||||||||||||
Case type | Straight, belted | |||||||||||||||||||||||
Bullet diameter | .458 in (11.6 mm) | |||||||||||||||||||||||
Neck diameter | .481 in (12.2 mm) | |||||||||||||||||||||||
Base diameter | .513 in (13.0 mm) | |||||||||||||||||||||||
Rim diameter | .532 in (13.5 mm) | |||||||||||||||||||||||
Rim thickness | .050 in (1.3 mm) | |||||||||||||||||||||||
Case length | 2.800 in (71.1 mm) | |||||||||||||||||||||||
Case capacity | 110 gr H2O (7.1 cm3) | |||||||||||||||||||||||
Rifling twist | 1 in 14 | |||||||||||||||||||||||
Primer type | Large Rifle (Magnum) | |||||||||||||||||||||||
Maximum pressure | 62,000 psi (430 MPa) | |||||||||||||||||||||||
Ballistic performance | ||||||||||||||||||||||||
|
The .458 Lott is a .458 caliber belted hunting cartridge designed as a replacement for the less powerful .458 Winchester Magnum. It is based on the full length .375 H&H Magnum blown out and shortened to 2.800 inches (71.1 mm). The cartridge is designed for the purpose of hunting African dangerous game.[1]
The .458 Lott was designed in response to perceived inadequacies and problems encountered with the .458 Winchester Magnum. While the cartridge was slow to gain popularity at first, it is now becoming the standard by which dangerous game cartridges are judged. The cartridge provides a distinct step up in performance over the .458 Winchester Magnum. A-Square, Česká Zbrojovka/Brno, Hornady and Ruger have been instrumental in the cartridge rise in popularity.
Cartridge History
The .458 Winchester Magnum was put into production in 1956 and was an immediate commercial success. It was a more economical alternative to the English double rifles that were considered the standard rifle type for dangerous game hunting in Africa. The .458 Winchester Magnum promised to emulate the performance of the .450 Nitro Express in a cartridge designed for a standard length bolt action rifle.[1] However, it soon became apparent that the .458 Winchester Magnum was not performing as anticipated. Several factors contributing to its at less than stellar performance in Africa: clumping of its compressed powder charge[2] and use in 20–22 in (510–560 mm) barrel rifles.[3]
Jacque (Jack) Lott, a big game hunter and a noted writer, had an adverse encounter in Mozambique in 1959 with an African Cape buffalo in which he sustained injuries.[4] He had been hunting with the then new .458 Winchester Magnum.[5] This experience convinced him that a more powerful cartridge than the .458 Winchester Magnum was required when hunting dangerous game. After the encounter he began a search for a big bore cartridge which would suit his needs perfectly.[6]
Not finding a cartridge that would fit his needs, he designed a cartridge which he felt would meet his requirements in a dangerous game cartridge. Jack Lott's original drawings of the cartridge were on a napkin at a diner. The first cases for the new rifle cartridge were fireformed from .375 H&H Magnum brass into a chamber by using .458 caliber (11.6 mm) bullets which had their bases were sized to .375-inch (9.5 mm) so as to fit in the mouth of the .375 H&H Magnum. This method of fireforming left the newly formed cases slightly shorter than the parent cases. The resulting cartridge is named the .458 Lott in his honor.[6]
In 1989 A-Square became the first company to offer the .458 Lott as a commercial cartridge. At present, the 465-grain (30.1 g) Triad (Monolithic Solid, Dead Tough and the Lion Load) for the .458 Lott cartridge is available from the company.[7] A-Square was also championed the successful SAAMI standardization of the .458 Lott cartridge which took place in 1995. They currently offer the A-Square Hannibal and Caesar rifles chambered for this cartridge.
Design & Specifications
The objective behind the design of the .458 Lott was provide a greater case capacity over the .458 Winchester Magnum so as to provide better performance and less compression of the powder charge. The .458 Lott achieved both these objectives by its lengthened cartridge. Furthermore, as the Lott cartridge is essence a lengthened .458 Winchester Magnum, converting to a .458 Winchester Magnum involves in many case a simple re-boring of the chamber and if required, a lengthening of the magazine.
The .458 Lott was standardized by SAAMI in 1995 based on specification provided by Arthur Alphin and A-Square LLC. According to Arthur Alphin, the cartridge length was standardized at 2.800-inch (71.1 mm) and the chamber length at 2.810-inch (71.4 mm) because there were many converted rifles in the field that were chambered for the original Jack Lott length.
The specifications for the .458 Lott call for a cartridge which gradually tapers. However, A-Square and few other ammunition manufacturers provide a ghost shoulder for the cartridge which was not included in the specification as standardized by SAAMI. Arthur Alphin chose not to include the ghost shoulder to remain true to Jack Lott's wishes and to honor his memory. The ghost shoulder serves to provide better retention of the bullet in the case under recoil.
SAAMI recommends a 6 grove rifling contour with each grove being .150-inch (3.8 mm) wide. Distance between lands is .450-inch (11.4 mm) and between groves is .458-inch (11.6 mm). Recommended rifling twist is between 1:10 to 1:20. Most rifle manufacturers use 1:14 or 1:16 twist rates.
Since Lott was a influential big-game hunter and writer the cartridge gained some attention with professional hunters in Africa. The .458 Lott was soon commercialized by A-Square as a proprietary cartridge.[6] CZ chambered the cartridge in their BRNO ZKK 602 rifles based on the Magnum Mauser action. However, the Lott remained fairly obscure at least in the United States until Ruger offered the cartridge in their Ruger M77RSM Mk II rifles to the American public in 2002.[8] Since then there has been a slow but steady movement away from the .458 Winchester Magnum towards the .458 Lott among professional hunters heading to Africa.[6]
The .458 Winchester Magnum is ubiquitous in Africa. While one might not be able to easily find ammunition for the big Weatherby or the Nitro Express cartridges, due to its popularity one would be able to find .458 Winchester Magnum cartridges. In an emergency, the .458 Winchester Magnum can be fired in the chamber of a .458 Lott.
Variants
Prior to the arrival of the .458 Lott there were a few other .45 caliber (11.6 mm) cartridges with similar performance levels based on the full length .375 H&H Magnum case such as the .450 Ackley Magnum, .450 Barnes Supreme, .450 Mashburn Magnum and the .450 Watts Magnum.[9] There are only minute variations between these cartridges.[3] Most .458 Lott chambers will accept the .450 Watts cartridge as the chambers are reamed to accept a 2.850 inches (72.4 mm)* cartridge.[10][11] The .458 Lott chamber will not accept an improved cartridges like the .450 Ackley Magnum and the .450 Barnes Supreme. Depending on chamber dimensions it may accept the Watts version of the cartridge. However strict SAAMI chambers will not accept the .450 Watts Magnum and any attempt to discharge it in such a chamber will invariably result in higher pressures and catastrophic failures may result.[9]
.450 Ackley Magnum
The .450 Ackley Magnum was designed in 1960 by Parker Otto Ackley.[1] The .450 Ackley Magnum can be considered an improved cartridge in comparison with the .458 Lott. The cartridge has minimum body taper ending with a small shoulder. Case capacity and performance is slightly greater than that of the .458 Lott resulting in less 50-foot-per-second (15 m/s) in velocity at equal pressures. Chamber will accept the Lott and Watts cartridges. The .458 Winchester Magnum can be fired in the chamber in an emergency. The .450 Barnes supreme cannot be fired in the chamber of the .450 Ackley as there are minute dimensional differences which may prevent the cartridge from chambering.[9] A-Square currently loads this cartridge with a 465-grain (30.1 g) bullet at 2,400-foot-per-second (730 m/s).[12]
.450 Watts Magnum
The .450 Watts Magnum was designed by Watts and Anderson of Washington State. The .450 Watts Magnum is similar to the .458 Lott with the exception of case length which is 2.850-inch (72.4 mm).[1] While the case capacity is slightly more than that of the Lott cartridge, the maximum overall cartridge length is the same. As this is the case, once the bullet is seated case powder capacity is almost identical. Chamber will accept the .458 Lott cartridge without issue. The .458 Winchester Magnum can be fired in the chamber if required. The .450 Watts can be fired in the chambers of the .450 Ackley Magnum, .450 Barnes Supreme and the .450 Mashburn Magnum chambers.[9] Firing the case in an improved chambers similar to that of the Ackley or the Barnes cartridges will result in a slight reduction in performance.
Performance
By the 1970 Winchester was forced to deal with the clumping of the compressed powder charge which had been resulting in improper ignition and poor performance. Winchester's remedy was to lessen the compression of the powder column. The result was a .458 Winchester Magnum that was now attaining only about 1,950-foot-per-second (590 m/s).[10] This was 200 ft/s (61 m/s) below what Winchester's original design specifications intended. The .458 Winchester Magnum was originally supposed to duplicate the performance of the .450 Nitro Express which could fire a 500 gr (32 g) bullet at 2,150-foot-per-second (660 m/s).
On the other hand, the .458 Lott is designed to provide about 200–300-foot-per-second (61–91 m/s) more velocity than the .458 Winchester Magnum. The performance goal does not just match but exceeds the original performance specifications of the .458 Winchester Magnum. The cartridge is capable of firing a 500-grain (32 g) bullet at 2,300-foot-per-second (700 m/s) from a 23-inch (580 mm) barrel such as the Ruger M77. This capability easily exceeded the performance that was expected of the .450 Nitro Express and the .458 Winchester Magnum. The Lott cartridge was a distince step up from the .458 Winchester Magnum and the .450 Nitro Express cartridges. The .458 Lott is also considered a better cartridge for dangerous game hunting that the .470 Nitro Express when judged on its effects on big game.[3]
Due to its development and purpose, the performance of the .458 Lott is often compared with that of the .458 Winchester Magnum. This is inevitable as the latter was there cartridge which the .458 Lott was designed to replace.
Cartridge | Criteria | Muzzle | 50-yard (46 m) | 100-yard (91 m) | 150-yard (140 m) | 200-yard (180 m) | 250-yard (230 m) | 300-yard (270 m) |
.458 Winchester Magnum Hornady 500 grains (32 g)* DGS[13] | Velocity | 2,140 ft/s (650 m/s) | 2,007 ft/s (612 m/s) | 1,879 ft/s (573 m/s) | 1,757 ft/s (536 m/s) | 1,641 ft/s (500 m/s) | 1,531 ft/s (467 m/s) | 1,429 ft/s (436 m/s) |
Energy | 5,084 ft⋅lbf (6,893 J) | 4,472 ft⋅lbf (6,063 J) | 3,921 ft⋅lbf (5,316 J) | 3,428 ft⋅lbf (4,648 J) | 2,990 ft⋅lbf (4,050 J) | 2,603 ft⋅lbf (3,529 J) | 2,267 ft⋅lbf (3,074 J) | |
.458 Lott Hornady 500 grains (32 g)* DGS[14] | Velocity | 2,300 ft/s (700 m/s) | 2,162 ft/s (659 m/s) | 2,029 ft/s (618 m/s) | 1,900 ft/s (580 m/s) | 1,777 ft/s (542 m/s) | 1,660 ft/s (510 m/s) | 1,549 ft/s (472 m/s) |
Energy | 5,873 ft⋅lbf (7,963 J) | 5,190 ft⋅lbf (7,040 J) | 4,568 ft⋅lbf (6,193 J) | 4,007 ft⋅lbf (5,433 J) | 3,505 ft⋅lbf (4,752 J) | 3,058 ft⋅lbf (4,146 J) | 2,663 ft⋅lbf (3,611 J) | |
Values courtesy of the Hornady Ballistic Calculator[15] For the purposes of this comparison barrel a barrel length of 24 in (610 mm) is used. |
![458 Lott bullet velocity](http://upload.wikimedia.org/wikipedia/commons/thumb/d/dc/458LottBulletVelocity03.png/400px-458LottBulletVelocity03.png)
![458 Lott bullet energy levels](http://upload.wikimedia.org/wikipedia/commons/thumb/7/73/458LottBulletEnergy03.png/400px-458LottBulletEnergy03.png)
The .458 Lott is able to attain over 2,300-foot-per-second (700 m/s) with a 500-grain (32 g) jacketed bullet at safe pressure levels from a 23–24-inch (580–610 mm) barrel. In comparison, many ammunition manucacturers load the .458 Winchester Magnum to velocities between 2,050–1,950 ft/s (620–590 m/s).[16][3] Hornady's Superformance ammunition being an exception which uses powder blends which at present remain unrealsed to the public.[17] The .458 Lott is capable of reaching a velocity of 2,150-foot-per-second (660 m/s) with the 600-grain (39 g) bullet which is greater than the velocity reached by Hornady's 500-grain (32 g) Superformance .458 Winchester Magnum ammunition. With lighter bullets of 300-grain (19 g) it is able to to achieve a velocity of about 2,850 ft/s (870 m/s). These energy and velocity values provide the .458 Lott cartridge a gain of between 50–100 yd (46–91 m) over the .458 Winchester Magnum in distance. This performance increase provides better penetration and stopping power against dangerous game than the .458 Winchester Magnum.
However, the mono-metal bullets fall short of this velocity threshold due to the need to seat the bullets deeper owing to the length of the bullets and the need to stay within the maximum overall length specification of the cartridge. This is because of the lower mono-metal bullets have a higher length to weight ration than conventional bullets. Manufacturers such as A-Square have chosen to load slightly lighter bullets 465-grain (30.1 g) instead of the 500-grain (32 g) bullets.[7][18]
The straight tapered case of the .458 Lott provides greater flexibility in reloading to lower velocities that bottlenecked cartridges. The ability to reload ammunition to lower velocities with lighter bullets can provide shooters with ammunition with less recoil that the full power .458 Lott ammunition. Nayati Inc., an big bore ammunition manufacturer, has taken advantage of this flexibility and offers ammunition featuring a 500-grain (32 g) copper jacket bullet at 1,100-foot-per-second (340 m/s). They also offer intermediate power ammunition for the .458 Lott as well.[19]
Handloaders can take advantage of the wide range of bullet of useful weights are available in .45 caliber for the .458 Lott cartridge. Bullets ranging from 300–600 gr (19–39 g) can be loaded for the Lott cartridge. This, together with the ability to load the cartridge to lower power levels, easily adds to the versatility of the .458 Lott. .458 Lott velocities range from 3,000 ft/s (910 m/s) with the 300 gr (19 g) bullet and 2,150 ft/s (660 m/s) with the 600 gr (39 g) bullet. Spitzer bullets with better ballistic such as the Barnes X or TSX bullets provides better down range performance over the more conventional .45 caliber (11.6 mm) bullets. The .458 Lott does well with hardcast lead bullets. With these bullets the Lott can be loaded to power level of the original .45-70 Government cartridge which was a 405 gr (26.2 g) bullet at 1,330 ft/s (410 m/s).
What the .458 Lott lack in velocity and energy in comparison to the .450 Rigby or the .460 Weatherby Magnum, it more than make up for this in its versatility. Larger volume cases such as the .460 Weatherby Magnum do not do well with powder charges below the recommended minimums. This is due to erratic ignition and hangfires issues experienced when large capacity cartridges are loaded with small powder charges. On the other hand the Lott has no such issues and takes well to lower powder charges.
Sporting Usage
The .458 Lott was designed as a dangerous game rifle cartridge. It is considered an ideal cartridge for hunting African dangerous game and is capable of taking game from elephant to the duiker. Acceptable bullet weights for the .458 Lott range from 300-to-600-grain (19 to 39 g). The range of available bullets provides the flexibility to customize loads for specific game species.[11]
Elephant require a bullet of a tough construction which will not deform easily. The bullet has to penetrate heavy bone and exit from all possible angles. These requirement reduce the useful choices to solid bullets.[20] Cape buffalo and rhinoceros, though tough and thick skinned will require solid or soft point bullets of a sturdy construction which can break through bone and penetrate to the vitals. Soft points similar to the A-Square Dead Tough[7], Barnes TSX[21], Hornady DGX[22] and the Woodleigh Weldcore Soft Nose[23] are examples of these bullets. The .458 Lott has ample power to spare on these species.
While the .458 Lott is capable of taking lion and leopard, it is considered overly powerful for the big cats.[24] Lighter bullets which expand quickly or fragment at higher velocities are usually recommended for the big cats. A-Square Lion Load bullet fills this niche for the .458 Lott.[7]
In North America is would make a fine big bear and bison rifle.[25] However apart from these species, North American big game does not require cartridges similar to the .458 Lott. Those who reload ammunition are able to take advantage of the .458 Lott's performance flexiblity to tailor their ammunition to the species of game they wish to hunt.
Criticism
There has been some criticism of the cartridge for its inability to reach the magical 2,300–2,400 ft/s (700–730 m/s) velocity some hunter believe is required for a dangerous game cartridge with certain propellants. This is a particular concern outside North America where only particular lines of cartridge powders are available, sometimes of local manufacture. While the Lott achieves this velocity, the powders used may not be available in most locals.[2]
This is particular true in many African nations. In South African, where the local Denel Somchem powders are readily available, none of the powders have the capability of launching a 500-grain (32 g) bullet at 2,300 ft/s (700 m/s). This lead to the creation of a new cartridge named the .458 Express by its designer Dr. Koos Badenhorst. The new design uses a 3-inch (76 mm) cartridge made from basic .458 brass based on the .375 H&H Magnum casehead. This case provided the capacity necessary using Somchem powders such as S321 and S335 to drive the 500-grain (32 g) to 2,300 ft/s (700 m/s).[2]
See also
References
- ^ a b c d Barnes, Frank C. (2006) [1965]. Skinner, Stan (ed.). Cartridges of the World (11th Edition ed.). Gun Digest Books. p. 552. ISBN 0-89689-297-2.
{{cite book}}
:|edition=
has extra text (help) - ^ a b c Koos Badenhorst. "458 Express History". 458express.com. 458express.com. Retrieved 11 September 2010.
- ^ a b c d Pappas, Cal. "The .458 Watts/ .458 Lott". African Hunter. Front Sight. Retrieved 10 September 2010.
- ^ Wieland, Terry (2006). Dangerous-Game Rifles. Countrysport Press. p. 148. ISBN 978-0892726912.
{{cite book}}
: More than one of|pages=
and|page=
specified (help) - ^ "458 Lott". norma.cc. Norma. Retrieved 10 September 2010.
- ^ a b c d Steele, Kevin E. J. "Buff Busters". rifleshootermag.com. Petersen.s Publications. Retrieved 10 September 2010.
- ^ a b c d ".458 Lott 465 gr. Triad". http://a-squareco.com. A-Square. Retrieved 13 September 2010.
{{cite web}}
: External link in
(help)|work=
- ^ Bodinson, Holt J (July 2005). "Ruger's buffalo rifle: it ain't no Sharps, but it shoots like one". Gun Magazine. Firearms Marketing Group. Retrieved 10 September 2010.
- ^ a b c d Vincent, Roy (June/July 2007). "The .450 Ackley Magnum". africanoutfitter.com. African Outfitter Magazine. Retrieved 20 September 2010.
{{cite web}}
: Check date values in:|date=
(help) - ^ a b Pappas, Cal (13 February 2009). "The 458 Watts vs 458 Lott". Safari & Outdoor. Safari & Outdoor. Retrieved 12 September 2010.
- ^ a b Hansen, Norbert (8 December 2009). "The Cartridge .458 Lott or .450 Watts and .450 Ackley Magnum". africahunting.com. Africa Hunting. Retrieved 12 September 2010.
- ^ "A-Square Ammunition". http://a-squareco.com. A-Square. Retrieved 23 September 2010.
{{cite web}}
: External link in
(help)|work=
- ^ "Hornady .458 Winchester Magnum 500 gr. DGS Super Performance". Hornady. Retrieved 22 August 2010.
- ^ "Hornady .458 Lott 500 gr. DGS". Hornady. Retrieved 22 August 2010.
- ^ "A Hornady Ballistics Calculatorl". hornady.com. Hornady Manufacturing Company. Retrieved 11 September 2010.
{{cite web}}
: Cite has empty unknown parameter:|1=
(help) - ^ "Rifle Ammunition". federalpremium.com. Federal Premium Ammunition. Retrieved 2 October 2010.
- ^ NRA Staff. "Hornady Superformance Ammunition". americanhunter.org. NRA Publications. Retrieved 2 October 2010.
- ^ Haley, Charlie. "Solids vs Mono-metal Bullets - Which is Best?". African Hunter Magazine. Retrieved 20 August 2010.
- ^ "458 Lott Practice Ammunition". nyatiinc.com. Nyati Inc. Retrieved 23 September 2010.
- ^ "Hunting Elephant Today". grosswildjagd.de. Gross WildJagd. Retrieved 13 September 2010.
- ^ "TSX Bullet". barnesbullets.com. Barnes Bullets. Retrieved 13 September 2010.
- ^ "DGX". hornady.com. Hornady Manufacturing Company. Retrieved 13 September 2010.
- ^ "Weldcore Soft Nose". woodleighbullets.com.au. woodleigh bullets. Retrieved 13 September 2010.
- ^ "Rifles for Hunting Dangerous Game". firearmssite.com. Firearms Site. Retrieved 12 September 2010.
- ^ Hawks, Chuck. "Rifles for Dangerous Game". Chuck Hawks. Retrieved 12 September 2010.
{{cite web}}
: Text "workchuckhawks.com" ignored (help)