#Performance

Smith and Wesson make fantastic production revolvers but when they apply their Performance Center treatment, with custom features, a revolver becomes something even more special.

Previously, we compared the Russian 9x39mm subsonic sniper round to its Western counterparts, including the .300 AAC Blackout and the .45 ACP. As it stands now, the 9x39mm is a subsonic round only – no supersonic loads exist for it currently. But… What if they did?

Today’s Modern Intermediate Calibers will handle something a little different. While virtually all rounds we have looked at so far were designed primarily for supersonic use, today we will be taking a gander at the Russian 9x39mm round – a dedicated suppressed caliber designed exclusively for the subsonic flight regime, with no supersonic option (yet) available. This begets a question, then: Is the 9x39mm truly an intermediate caliber? To answer this, we should consider a few facts about the 9×39: First, it was designed for carbines and rifles with cartridge overall lengths comparable to common intermediate calibers, like 5.56mm or 7.62×39. Second, it was designed to give substantially better performance than is possible with pistol rounds, including armor piercing effect above that which is normally possible with handgun rounds. Third, it is used more like an intermediate caliber than a pistol caliber, being issued with a whole host of sniper rifles, assault rifles, and other weapons comparable to any other intermediate caliber. Therefore, I would argue that it is an intermediate, albeit possibly the strangest one in common use.

The defense magazine European Security & Defence has published an article detailing for the first time Glock’s Modular Handgun System submission and its Federal-engineered ammunition. The article – part technical overview, part interview, details the recent history of Glock’s MHS submission, the technical characteristics of their Glock 19 MHS and 23 MHS pistols, and the current feeling among Glock executives about their second place finish in the competition. I highly recommend our readers head over the the ES&D website, where they can read the full article for free in text only or PDF form. But, since I don’t want to bury the lede any more than I have, here’s what Glock’s head of International Sales, Richard Flür, had to say on the Glock MHS’s future beyond the US Army:

So far in the Modern PDW Calibers series we’ve talked about small caliber, high velocity PDW rounds like the 5.7mm FN and 4.6mm HK, and we’ve tackled larger, punchier calibers like the 10mm Norma Auto and the 7.5mm FK. However, we still have not tackled the very extreme low end of the spectrum, that is rounds that are so small and impotent that many question their usefulness as antipersonnel rounds at all. However, small size brings with it some benefits in recoil and round weight, so it’s worth taking a closer look at this kind of round.

The US .30 cal M1 Carbine is one of the most important developments in the personal defense weapon story, being one of the very first* intermediate calibers to be adopted as standard issue by a nation, and arguably the first purpose-designed PDW caliber in history. Even today it occupies a strange halfway point between pistol and rifle cartridges, being similar in design to a long pistol round or magnum revolver round with its straight-walled case and round-nosed bullet, but loaded with rifle powders designed for the 18″ barrel of the handy little M1 Carbine.

Today on Modern PDW Calibers we’re going to look at what might seem like a humdrum round, but which represents an important performance band for the modern personal defense weapon. That round is the 5.56x30mm MARS, a purpose built “micro assault rifle” cartridge from Colt designed to fill a similar niche to the WWII-era .30 M1 Carbine.

If the 5.7x28mm FN is the first successful modern PDW round, then the 4.6x30mm HK is the second, and its biggest rival. German firm Heckler and developed the microcaliber 4.6mm in the 1990s as a response to a NATO solicitation for a Personal Defense Weapon, to which they submitted their new HK PDW (later MP7) chambered for the new round.

Like the .300 AAC Blackout that we discussed earlier, the 7.62×40 Wilson Tactical was intended to be a medium-performance .30 caliber cartridge that would function in standard AR-15 type rifles with minimal modifications, such as a barrel change. Also like the .300 AAC Blackout, the Wilson round was based on an earlier wildcat, which was designed by Ken Buchert and also called the 7.62×40. Unlike the .300 Blackout, however, the 7.62x40mm Wilson Tactical sacrificed some versatility for raw power in the form of a lengthened case based on the 5.56mm case, instead of the .221 Remington Fireball used by the Whisper/Blackout. This longer case gives the 7.62×40 WT a significant performance advantage over the .300 Blackout from comparable barrel lengths, but it limits how ballistically efficient the projectiles used by the round can be. In theory, the 7.62×40 WT can also be loaded with subsonics, like the .300 AAC Blackout, although the short ogive length limits which COTS bullets can be used for this, and no factory subsonic ammunition exists for the Wilson round. This makes the 7.62×40 WT virtually a dedicated supersonic hunting or 3-Gun round (in which it makes Major Power Factor), but it is still worth considering in our discussion. Now, on to the ballistics:

Previously, we talked about the Soviet 7.62x39mm caliber, which was paired with the famous Kalashnikov automatic rifle. With its much heavier bullet, larger caliber, and lower velocity, the 7.62x39mm contrasts heavily with the US 5.56mm caliber, and US weapons manufacturers took note. The .300 AAC Blackout is in many ways similar to the 7.62x39mm caliber, being – like the 6.8 SPC – inspired by it, but designed to add new capabilities. The origin of the Blackout lies in the earlier .300 Whisper, a wildcat developed by JD Jones from the .221 Remington Fireball to fire both heavy subsonic projectiles and lighter supersonic rounds with ballistic characteristics similar to the 7.62x39mm, while being highly compatible with existing AR-15 type rifles. Versus the older Whisper, the Blackout is little changed, but its introduction, backed by the force of Advanced Armament Corp, Remington, Barnes, and other companies, made it virtually an overnight success on the US civilian market.