RELOADING
New Loading Manual for Barnes' New Bullets!
Barnes' new loading manual has extensive data for TSX, MRX, XPB bullets and more!
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It does all of that very well, but the shooting public took a while to accept the new approach to expanding bullets. Once accepted, though, the line hasn't stopped growing or improving since.
One of the first improvements came during the moly-coating craze of the late 1990s, and Barnes' response was the XLC bullet. It was nothing more than a regular X-Bullet coated with a robin's egg blue proprietary dry film lubricant. Claims of velocity increases over the non-coated X-Bullet by as much as 200 fps were made and validated in the Barnes Reloading Manual Number 3. Actually, there were instances of even greater velocity increases. For example, the maximum load for the 180-grain Barnes X-Bullet in the .30-06 clocked at 2,796 fps. The coated bullet, however, bettered that velocity by a significant 295 fps. And lest anyone think that data was hedged in favor of the XLC, consider that even the slower Barnes loading exceeded the velocity of many 180-grain .30-06 factory loads.
My first exposure to a major X-Bullet variation was in 2003 while hunting Coues deer in Old Mexico with John Lazzeroni. Lazzeroni needed a bullet that would hold up to the formidable velocity his proprietary line of cartridges generated yet still deliver terminally on the pointy end downrange—even if it was at very long range. To that end, he showed me a grooved X-Bullet that was all black. The LazerHead, as he called it, was an X-Bullet made slightly undersize, grooved around its circumference, and then plated up to diameter using Robar NP2 PTFE dry film lubricant.
The grooves reduce the bearing surface and engraving forces on the bullet. This is an important improvement considering that all-copper bullets are longer than lead-core bullets of the same weight and diameter, and thus have a much greater bearing surface. That same year, Barnes legitimized the grooved X-Bullet as the TSX, and Federal began loading it in its Premium line of factory ammunition.
By 2006, the X-line had expanded to include the grooved MRX, or Maximum Range X-Bullet. There are two major changes with this bullet. First, instead of being all copper it has a rear core made of tungsten alloy. Second, the fine hollowpoint for which the X-Bullet is known is larger and plugged with an extremely pointy Delrin tip.
There are several effects from the tungsten core. It moves the center of gravity toward the rear of the bullet, and while that would tend to increase the overturning moment and reduce bullet stability, the core is denser than the copper it replaces, which makes the bullet shorter than the all-copper TSX, and that increases stability.
As for the tip, I've never known an X-type bullet to need one to facilitate expansion. It's true that for the same weight and caliber MRX bullets have a higher ballistic coefficient than TSX bullets, so maybe there's some benefit there. Ultimately, it may be that since this is Barnes' premium rifle bullet, and polymer tips are in vogue on premium bullets, it's there as much for appeal as for performance.
The most recent addition to the Barnes rifle bullet line is the Tipped TSX, or TTSX. It differs from the standard TSX in that it has a redesigned nose cavity with the Delrin tip found in the MRX bullet. Again, I'm not sure the tip is necessary for expansion, but it does allow the TTSX to have the larger hollowpoint cavity and still retain the pointed profile for increased ballistic coefficient.
Along the way there have been other Barnes rifle bullets that were or are not necessarily all copper—not the least of which are the lead-core Barnes Original and copper/zinc alloy Banded Solids.
