May 18th, 2011

Wilson Combat’s New 7.62×40 WT Cartridge for AR Platform

Wilson Combat has come up with a new cartridge, dubbed the 7.62×40 WT (Wilson Tactical). Basically it is a .223 Remington necked up to .308 caliber, i.e. a .30-.223 Rem Wildcat. The cartridge is designed to give .30-cal capability to a standard AR15, using the normal bolt assembly and standard AR15 magazines. An AR15 can be converted to shoot the 7.62×40 WT with just a barrel swap. Note: Don’t confuse this new cartridge with the 7.62×39, the Eastern Bloc military cartridge that has been around for decades. The 7.62×40 WT is not derived from the 7.62×39 in any way. The 7.62×39 has a larger rim size, more body taper, and requires a different magazine and bolt. There have been 7.62×39 adaptations for ARs, but most didn’t function well (usually because of magazine issues). Wilson Combat claims the 7.62×40 WT offers the hitting power of the 7.62×39, but with a cartridge design that feeds and functions 100% in an AR15.

Wilson Tactical 7.62x40 WT

The 7.62×40 WT was designed around an optimal overall cartridge length of 2.250” which is a perfect fit for standard AR mags without shoving the bullet too far down in the case. Wilson says that its 7.62×40 WT barrels are optimally throated for the 2.250″ COAL. Therefore, Wilson claims, the “7.62×40 WT does not suffer from the same inconsistent accuracy issues in the AR platform often seen with the 300 Whisper and 300 BLACKOUT.”

Wilson Tactical 7.62x40 WT

Here are comparative Velocity and Energy numbers for the 7.62×40 WT vs. other cartridges with which it will compete.

7.62×40 WT (16″ Barrel)
110 gr: 2450 FPS Muzzle Velocity and 1466 Foot Pounds of Energy
125 gr: 2400 FPS Muzzle Velocity and 1599 Foot Pounds of Energy
150 gr: 2200 FPS Muzzle Velocity and 1612 Foot Pounds of Energy

5.56 NATO (.223 Rem) (16″ Barrel)
55 gr: 3150 FPS Muzzle Velocity and 1212 Foot Pounds of Energy
62 gr: 3000 FPS Muzzle Velocity and 1239 Foot Pounds of Energy
77 gr: 2750 FPS Muzzle Velocity and 1293 Foot Pounds of Energy

7.62×39 (16″ Barrel)
123 gr: 2320 FPS Muzzle Velocity and 1470 Foot Pounds of Energy

6.8 SPC (16″ Barrel)
110 gr: 2550 FPS Muzzle Velocity and 1594 Foot Pounds of Energy

Wilson Tactical 7.62x40 WTAt first it looks like the 7.62×40 WT has more energy than a 7.62×39 and outruns a 6.8 SPC handily. But Wilson omitted some key data for the 7.62×39. Taking load info straight from the Hodgdon Reloading Center, a 7.62×39 can be loaded to 2408 fps with a 125gr bullet, or to 2192 fps with a 150gr bullet at relatively moderate pressures (under 41,000 CUP, or roughly 44,250 psi). A 7.62×39 launching 150-grainers at 2192 fps generates 1601 foot-pounds, virtually the same as Wilson’s 150gr load. So, the 7.62×40 WT has no real advantage (over the 7.62×39).

Is This Cartridge Needed at All?
The “T” in 7.62×40 WT stands for “Tactical”, but we don’t think many police or military units will adopt this round. The 5.56x45mm is too well-established in the AR15/M16 platform and the 7.62×39 is the smart .30-Cal choice for an AK. So what, then, is the real “niche” for the 7.62×40 WT?

We think this round may prove popular with hunters who want to shoot a much heavier bullet out of a standard AR. A 150gr projectile is nearly twice as heavy as the biggest projectile you can shoot from a .223 Rem AR. The bigger bullet should work better on some kinds of game. Wilson Combat says: “Designed for tactical/defense applications as well as hunting for medium-sized game such as deer and feral hogs. For hunting the 7.62×40 WT vastly out performs the 5.56 and is on par with the 6.8 SPC at ranges out to 175-200 yards. The VERY mild recoil of the 7.62×40 WT also makes it ideal for female and younger shooters as well as anyone that’s recoil sensitive.”

Wilson says the 7.62×40 has proven itself as a good hunting cartridge: “A LOT of Texas feral hogs, whitetail deer and predators lost their lives testing the terminal performance of this cartridge! The 7.62×40 WT has proven to be a VERY efficient killer on medium sized game with the 110gr Barnes TTSX, 125gr Nosler Ballistic Hunter and the 125gr Sierra Pro Hunter. Any of these three bullets perform admirably on deer and hogs under 150 lbs. or so, but we recommend the 110gr Barnes TTSX for large hogs. The 110gr Sierra HP is a great bullet in the 7.62×40 WT for varmints and predators, and has proven to be one of the most accurate bullets.”

Wilson Tactical 7.62x40 WTFor home defense, it could be argued that the 7.62×40 WT is better than the .223 Rem because the larger, slower .30-Cal projectile has less penetration (through walls), but that would have to be demonstrated with real-world testing. Moreover, there are frangible .224-cal bullets that minimize the risk of over-penetration indoors.

Some benchresters might even tinker with the 7.62×40 WT in a bolt gun for score competition, but we doubt it would prove competitive with the 30 BR which can push a 120gr bullet at around 3000 fps. Wilson’s cartridge does give a paper-puncher the ability to shoot a .30-caliber bullet from a rifle with a .223 bolt face, and that might be attractive to club shooters in informal score matches.

Wilson Combat will be selling 7.62×40 WT loaded ammunition (with 110gr or 125gr bullets), but it is also supporting the reloading market. Wilson offers 7.62×40 WT brass, Hornady 7.62×40 WT dies, and you’ll find extensive load data on the Wilson Combat website. For those who want to put together a 7.62×40 WT AR, Wilson offers pre-chambered 7.62×40 WT barrels, as well as complete 7.62×40 WT uppers. Barrels start at $249.95, while the 7.62×40 WT uppers retail for $1024.95.

Permalink Bullets, Brass, Ammo, Hunting/Varminting, New Product 17 Comments »
May 18th, 2011

JBM-Powered Ballistics Software for Apple iPads

iPad Ballistics softwareA dedicated iPad version of Ballistic (‘Ballistic’ App), a full-featured ballistics calculator for the iPhone, is available for the growing numbers of iPad users. As with the iPhone version, ‘Ballistic’ App for the iPad is “powered by JBM Ballistics” so it offers very precise solutions — typically, at 600 yards, JBM will get you within two or three clicks, provided you have good bullet BC data and reliable MV from your chronograph.

The ‘Ballistic’ App for the iPhone and iPad features a library of over 3,100 projectiles; the library includes the latest 2010 commercial data and G7 military coefficients from Aberdeen Proving Grounds. Along with calculating bullet trajectories, this software has many extra features. There are several different target cards so you can input shot placement and scoring is calculated automatically. There is also a range log (for recording shooting sessions), a mildot and MOA range estimator, and a convenient load database for storing your reloading recipes.

Special features in the iPad edition of ‘Ballistic’ App include: fully integrated split-screen ballistics, favorites, and range log; full-screen, hi-resolution charts; ballistics calculations update automatically as you edit; larger target sizes in range log; and screens can rotate. The iPad Ballistic App (release 2.3.7) costs $19.99. The standard version for iPhone and iTouch units, costs $9.99. To learn more about this software, visit ballistic.zdziarski.com.

Permalink Bullets, Brass, Ammo, New Product 2 Comments »