Home > Knowledge Base > .256 Newton and 6.5-06
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.256 Newton and 6.5-06HistoryCharles Newton has often been described as the father of high velocity. As a cartridge designer, Newton was born well ahead of his time in an era lacking in slow burning powders for his large capacity cases. Nevertheless he designed some very potent cartridges as well as patenting several experimental bullet designs. During the period in which Newton was involved in designing the .22 Savage Hi Power, it appears that Newton had doubts about the Hi Power's suitability for the medium game it was intended for. With it's 70 grain bullet at 2790fps these doubts became well justified. Newton continued to experiment with case design and in the same year (1912) that the Hi Power was released, Newton developed a hotter wildcat. The .22 Newton was based on the .30-06 case shortened by 1/4 inch and necked down to fire a 90 grain .228 caliber bullet at 3100fps. But the wildcat would not satisfy Newton and he immediately had other ideas for a high velocity small bore deer cartridge. The .22 Newton was put on the back burner and received no further attention until his friend, gunsmith Jerry Gebby started to explore its possibilities (see .22-250). Within a year, Newton had developed a cartridge based on the .30-06 simply necked down to 6.5 (.264") with a 17 degree shoulder. In 1913 Newton released his new cartridge the .256 Newton. Initially, ammunition was loaded by the Western Cartridge company who offered a 129 grain bullet at 2760fps. This was about as fast as powders of the day could drive bullets in the .256 and it would not be until the 1940's when slow burning powders would come onto the scene. The .256 was well received by the shooting public but in 1914 a new and more pressing situation arose - war. Committed to the First World War, the American army was forced to take over Newton's factory. By December of 1917, Newton had used the last of his stock of shells and projectiles and with no components or access to machinery, there was no market for his rifles. Newton eventually managed to borrow more money for extra machinery and by January 1918 had retooled up. In April of the same year the bank foreclosed on the loan and Newton's company went into receivership. The .256 remained factory loaded by Western until it finally dwindled into obsolescence in 1938. After the second world war, an influx of surplus Swedish Mauser’s reintroduced U.S hunters to the 6.5 caliber. With .30-06 brass more readily available than 6.5x55 brass it was natural that many 6.5 rifle barrels were put onto longer actions and reamed to the wildcat 6.5-06. The 6.5-06 differs from the .256 Newton only in shoulder angle, 23 degrees as opposed to Newton's 17 degree shoulder. Otherwise the two cartridges are identical in dimension and performance. Both the .256 and 6.5-06 have retained limited popularity and although rifles are no longer chambered in .256 Newton, some examples have survived to this day. The 6.5-06 is occasionally seen as a custom chambering. PerformanceDriving 120 grain bullets at 3150fps and 140 grain bullets at 2950fps, the .256 and 6.5-06 are flat shooting, hard hitting, fast killing cartridges. That said, it would be foolhardy to suggest that these 6.5’s have a ballistic advantage over the .270 Winchester within ordinary hunting ranges. Out to 300 yards, the 6.5’s and .270 slow down at an identical rate. A major difference in performance occurs when the 6.5’s are used specifically for long range match shooting and hunting. The 6.5’s can be loaded with match bullets which have much higher BC’s than .277” projectiles. Bullets such as the sleek 140 grain Hornady Amax and 140 grain Berger have extremely soft jackets which maximize wounding at longer ranges- and are extremely violent between 200 and 500 yards. These factors make the 6.5’s somewhat unique. The 6.5 caliber has been used over the last century to take a vast amount of large heavy game but such use does not work towards the strengths of this bore size. The 6.5’s are at their best on light to medium weight game and driven high velocity, do their work in a spectacular, emphatic manner. Factory ammunitionNo Factory ammunition is produced for either the .256 Newton or 6.5-06 wildcat. Hand loadingReloading Dies are readily available for both the .256 and 6.5-06 while cases are easily formed using .270 brass. IMR 4813 and H4813sc are both outstanding powders for the 6.5’s and realistic velocities from 24” barrels include 3150fps with 120 grain bullets, 3050fps with 129 grain bullets, 2950fps with 140 grain bullets and 2750 with 160 grain bullets. The comments made in the 6.5x55 section about bullet performance are just as relevant here, regardless of the extra velocity produced by the 06 length case. Soft conventional projectiles weighing between 120 and 140 grains do not produce deep penetration on densely muscled game due to theoretically high SD’s. Projectiles such as the Interlock, Pro-Hunter, GameKing, Ballistic Tip and Hotcor are best suited to lighter framed deer species. The ahead text serves as a brief recap on some of the more useful bullet designs. The 140 grain Hornady SST sees an increase in its already good performance when utilized in the 06 length case as opposed to the 6.5x55. Not only is wounding dramatic but also, high impact velocities cause the SST jacket to swage into itself after expansion which helps lock the jacket and core together. The 140 grain SST driven at 2950fps produces wounding that is much more diffused and disproportionate to caliber than is possible with the Swede when used at range. The Swede loaded with the SST begins to show a drop in performance on medium game past 200 yards (2400fps). On smaller deer species, the differences are mostly undetectable but on tough animals, there is a definite loss in killing power and shot placement becomes more critical. In the 6.5-06, this range is extended to 310 yards. The core bonded 129 grain InterBond, 130 grain Accubond and 130 grain Scirocco bullets all give excellent results in the .256/6.5-06. All can be driven at 3050fps and the results are emphatic. On medium game, the core bonded projectiles not only produce wide wounding but in most cases, the projectile creates a very fast bleeding exit wound even though the exit wound may only be .75” in diameter. Best performance occurs inside 275 yards, beyond which, all three gradually lose their ability to create wide internal wounds. As ranges exceed 300 yards, it becomes impetrative to take extra care with shot placement towards breaking major bones. These projectiles will take large bodied game but again, such use is not working with this cartridge’s strengths. As mentioned in the 6.5x55 text, the 140 grain Nosler Partition really is an extremely good bullet. The Partition has a BC of .490 and loaded to 2950fps, is adequately suited to taking shots on medium game as far as 550 yards (2000fps), a very good all-rounder. This bullet has the soft, violent, fast expanding features required for long range work yet is extremely reliable at point blank range. The 140 grain Partition reaches the limits of its excellent performance on Elk sized game. On larger animals, too much is asked of this bullet design and although the Partition will often produce fair results, ball joints and heavy bone can cause bullet blow up. For the toughest animals, nothing comes close to the Barnes TSX 120, 130 and 140 grain TSX and XLC bullets. Readers are reminded that although penetration with these bullets can be exceptionally deep, deep enough to take Bovines through both shoulders, wounding characteristics of the 6.5mm caliber are not optimal for game of this size. For specialized long range hunting, the 140 grain Hornady Amax (BC .550) and 140 grain VLD (BC .612) produce excellent performance down to 2000fps or 600 and 700 yards respectively, continuing to produce thorough wounding at velocities as low as 1800fps. At impact velocities below 2000fps, both have the capacity to render wide wounds however the VLD is more reliant on major bones to facilitate expansion. Closing commentsThe use of the 30-06 case (or lengthened 8x57 case, depending on ones demographical background) as a base for building 6.5 caliber cartridges, is as popular in Europe as it is elsewhere. Germany's 6.5x64 Brenneke and 6.5x65 RWS follow similar case dimensions to the .256 and 6.5-06. The most recent of these, the 6.5x65 was released in 1989, based on Dynamit Nobel's (owner of RWS ) realization of the need for a modern 6.5 to fulfill the demands of the German hunter. With a growing trend towards strong, light 90 to 130 grain controlled expanding bullets scribing ultra flat trajectories, the 6.5x65 case utilizes all available powder capacity with a shoulder over 4mm (.157" ) further forwards than other 30-06 based 6.5's, creating a short neck. In turn, rifles chambered in 6.5x65 have shorter throats than 6.5's of old which utilized long 160 grain round bullets. Instead the 6.5x65 chamber is designed with a decrease in bullet jump, enhancing accuracy with lighter bullets. The 6.5x65 is able to achieve realistic velocities of 3200fps with 120 grain bullets and 3000fps with 140 grain loads duplicating the wildcat 6.5-06 Ackley Improved. These cartridges represent about the maximum case size for which 6.5 bullets can be driven before overbore conditions arise including low velocity gains regardless of increases in case capacity and powder charges along with excessive throat erosion. The 6.5-06 Ackley Improved wildcat suffered from these effects during its earlier years. This problem has largely been minimized thanks to modern powders.
 
Note: For the 6.5-06 custom cartridge dimensions vary individually from the above. Discuss this article or ask a question on the forum here Copyright © 2007-2011 Terminal Ballistics Research, Ballisticstudies.com |
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