- Published: Monday, 18 November 2013 00:01
The 6.5-284 Norma
By Aaron Carter
Among the few “wildcat” cartridges to ever be legitimized, the 6.5-284 Norma has the distinction of being the only one to succeed when the parent cartridge—the 284 Win.—was a commercial failure. A fitting mythological comparison would be that of the phoenix rising from the ashes of ancestry; in this case, the “reborn” cartridge, the 6.5-284
Norma, is among, if not the, best long-range rounds extant for both competition and hunting. The path from creation to adoption was not only overly long, but it also required careful footing to ensure that it didn’t face a fate similar to that of its parent.
Winchester unveiled its short-action answer to the 270 Win. and 280 Rem. in 1963; however, its end design ultimately lead to its untimely demise. A true short-action cartridge, the 284 Win. has a maximum cartridge overall length (C.O.L.) of 2.800”,which, after deducting case length, leaves only 0.63” for bullet protrusion from the case
mouth. As such, lengthy 0.284”-diameter bullets have to be seated deeply, thus displacing propellant. The resulting reduction in propellant is quite detrimental to its external ballistics. The 284 Win. debuted in Winchester’s lever-action Model 88 and semiautomatic Model 100 rifles, which complemented it nicely; both rifles were chambered
for short-action cartridges. In hindsight, though, the 284 Win. might have fared better if it was initially offered in a bolt-action rifle. Regardless, today there are few new rifles are chambered in 284 Win., and many of the custom and semi-custom builders lengthen the throat to overcome the cartridge’s primary design weakness.
But, the 284 Win.’s case had unique design features endearing it to wildcatters. Foremost, the non-belted case featured a rebated rim equal in width to that of the .30-’06 Sprg., though its body diameter, which tapers from 0.500” ahead of the extractor to 0.475” rearward of the shoulder. The minimal body taper, when combined with a 35-
degree shoulder angle, enabled greater propellant capacity. The latter would be particularly appealing to those individuals who, above all else, demanded ultra-high velocities; remember, this was during the period during which the .264 Win. Mag., .300 Win. Mag., and other “high-performance” cartridges were unveiled. Additionally, the
propellant column was in the desirable short, fat column, which purportedly leads to increased accuracy. With this, the maximum average pressure (MAP) was set at an unusually high 56,000 copper units of pressure (C.U.P.); to handle such pressure, the case 1 is obviously quite strong. Given the aforementioned case characteristics, it’s little wonder that wildcatters necked it up and down to make use of bullets in popular diameters. Of the
resulting cartridges, the only one to gain commercial acceptance is the 6.5-284; however,
it was not standardized in its original form.
As with all wildcat cartridges, variances exist between chambers, dies and handloaded ammunition—nothing is “standard.” One commonality exists, however; most 6.5-284 Win.-chambered (short-action) rifles were created with the 2.800” maximum C.O.L. of the parent case in mind, and thus the throat length is relatively short. As such, the streamlined 6.5-mm projectiles must be seated deeply so as not to contact the lands. Doing so increases pressure, however, so when drawing from developed for the 6.5-284 Norma—the name and associated dimensions for the chambering as adopted as in 2001— only the mildest loads should be used. Dimensionally, the cases of the aforementioned
wildcat and factory offering are quite similar; however, Norma wisely elected to set the maximum C.O.L. at 3.228”, which allows lengthy match bullets to be set out substantially further, thus allowing more of the case capacity to be utilized for propellant, while also reducing pressure. But, elongating the cartridge eliminates its use in shortaction rifles unless fed singly or the magazine box is altered.
Long-range competitors are particularly fond of the 6.5-284 Norma. Why? Propelling bullets with high ballistic coefficients (BCs) to respectable velocities results in less time-to-target (and thus wind deflection), as well as reduced drop. Compared to proven performers of the past, such as the .300 Win. Mag., the 6.5-284 Norma’s recoil is
quite mild—thanks to lighter bullet weights combined with smaller propellant charges. Fatigue from recoil negatively affects performance, so less abuse without sacrificing performance is a huge advantage on the firing line.
Concerning barrel life, and depending on its treatment and maintenance, a shooter can expect to get approximately 1,000 through one before accuracy degrades to the level that it must be replaced; this is in line with, if not better than, other “overbore” highperformance cartridges such as the .257 Wby. Mag. and 7 mm STW. Competitors understand this and have replacements “at the ready.” When chambered in a hunting rifle, though, unless the shooter is careless with overheating or an ardent preparer for longrange encounters, it’s unlikely that he or she will “burn out” the barrel in a lifetime. The cartridge’s impressive performance makes it well worth the risk and investment. To
maximize downrange ballistics, barrels for 6.5-284 Norma-chambered rifles should not be less than 26” in length.
Serious competitors have specific throat lengths that they feel extract the best accuracy from the 6.5-284 Norma; usually it’s somewhere between 0.175” and 0.212”. The most accepted length is 0.212” (when combined with a 0.297”- to 0.298”-diameter neck); however, some shooters feel that, when starting with that length, by the time the “accuracy” load is found that they are past that number, so they elect to start at 0.175” or 0.188”. For the hunter shooting game at “typical” distances, this means little.
The same phenomenal external ballistics that endear the 6.5-284 Norma to many die-hard long-range competitors also interest a budding breed of hunters who excel at stretching the distance when situation dictates such. For a “mountain” or “African plains” rifle, where shot distances can be exponentially long, there’s likely no better choice; in fact, when loaded with streamlined hunting projectiles, the 6.5-284 Norma outperforms the vaunted 270 Win. at distances beyond 400 yds. For example, when loaded atop of 47.5 grs. of Ramshot Hunter, a Swift 130-gr. Scirocco II—with a BC of .571— propelled to 2,949 f.p.s. from the 26” barrel of my E.R. Shaw Mark VII rifle drops 3.4” at 300 yds.,14.6” at 400 yds. and 32.2” 500 yds. when zeroed at 250 yds. Despite its 3,250-f.p.s. muzzle velocity (factory-provided ballistics) the 120-gr. Kalahari from the 270 Win. Norma-USA American PH load drops 3.4” at 300 yds., 14.9” at 400 yds. and 34.4” at 500 yds. with the same zero. The key differences, however, are that the 6.5-mm bullet has an
additional 448 ft.-lbs. of energy at 500 yds., and it deflects off course 11.7” less at the same distance when encountering a mild, 10-m.p.h. full-value wind. Such performance is why serious long-range competitors and hunters “pay to play” with the 6.5-284 Norma.
As the number of 6.5-mm chamberings has increased, as well as interest in the caliber has grown, options in competition and hunting bullets has expanded as well; today, all major manufactures offer multiple projectiles suitable for punching paper or hide and, in some cases, they’re one and the same. Although manufacturers generally opt for lightweight, high-ballistic-coefficient 0.264” projectiles, and surely owing to its European connection, Norma-USA bucks the trend with veritable heavyweight—the 156- gr. semi-spitzer-shape Oryx. Designed for 90-percent-plus weight retention, the Oryx would be an excellent choice for the larger deer species, such as elk and moose, where deep penetration is required. Despite its relatively low BC—.348—the bullet, would be well suited for shots even out 300 yds. This projectile is also available factory loaded by Norma-USA in the American PH line, where it’s propelled to 2,790 f.p.s. and produces 2,697 ft.-lbs. of energy at the muzzle. To date, this is the only factory load that compares favorably with regard to accuracy to my handloads. Under the Norma Precision brand, the company offers a 120-gr. full-jacket Jaktmatch load for practice and a 130-gr. Golden Target round for competition.
Until standardized by Norma, acquiring cases for the 6.5-284 required reforming those of the parent case, and in most cases those were of dubious quality—if they could even be found. Fortunately, Norma-USA offers premium-quality cases that not improve the quality of one’s handloads, the number of reloads before discarding is increased, too. After testing several manufacturers’ cases, Norma-USA’s are my go-to choice.
Perhaps the 6.5-284 Norma’s only detraction, and then problematic for a few hunters, is the lack of “value-priced” ammunition. Then again, when you only have one shot that separates taking the podium or applauding the winner, or between grasping trophy rack or watching it disappear over the hillside, is that when you want to “cheap out” or cut corners? Didn’t think so. Demand premium performance, and that’s what the 6.5-284 Norma delivers.
Visit any reloading die maker’s custom area and you’ll quickly discover the sheer number of wildcats that have been created through the years to fill a niche—whether real or perceived. Few concepts ever make it beyond the “one-time” status. Fortunately, Norma had the insight to better and standardize the 6.5-284 Norma; had it not the shooting world would have foregone an amazing cartridge.
About The Author:
Aaron Carter was born and raised in Northern Virginia, Carter started hunting and trapping alongside his elders at early age. His budding interest in, and dedication to, the outdoors enabled Carter to begin writing authoritative articles at an early age; Carter's first piece, "Gunning for Geese," was written and published in NRA's youth-focused Insights magazine when he was 16 years old. After graduating college, Carter was hired as assistant editor for NRA's newsstand monthly, Shooting Illustrated. From there, he climbed the ranks until moving to the esteemed staff of American Rifleman, where he is currently managing editor. During his tenure with NRA Publications, Carter has written numerous bylined and non-bylined articles, reviews and evaluations, with several earning Gold and Platinum Awards from MarCom and Hermes Creative. In 2013, his works also earned him the coveted Nikon Ian McMurchy Award. His speciality is ammunition and hand loading; in fact, Carter created and pens the monthly column "Latest Loads," which presents an exciting new recipe 12 times a year. Whenever he's not hunting or at the loading bench, Carter can be found working on his small family farm and spending time with his sons, Gabriel, Colby, and Symon, and his wife, Bonnie.
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