When I bag on the process pushing the 6.8, I'm not saying an improved round wouldn't be a good idea, especially when the Army sacrificed the initial performance of the M193 round by stuffing the -16 with nasty, fouling ball powder instead of the stuff designed into the system. Which I think was a version of IMR that never made the commercial market, but definitely fouled less. Go ALL the way back, to the early 1950s, when the British developed the .280 EM-2 [actually a .276/7mm, usually described as the 7x44mm cartridge, or as the .280/30. Though the later version used the cartridge base and rim dimensions of the U.S. .30 cartridge in hopes that WWII-era manufacturing tooling and cartridge manufacturing machinery could be saved, an earlier versiou used a smaller diameter cartridge base and rim. And though the cartridge used a somewhat longer bullet [140 grain, IIRC] than most 5,56 ammunition, the slightly shorter case would allow the possibility of the use of the old EM-2 cartridge in weapons using a 45mm cartridge case: the 5,56x45mm M16 round and the Czech 7,62x45mm of the Vz52 carbine and Vz58 assault rifle in particular. That could allow ammunition development while the design and testing of such other possible platforms as the XM-8 or a *Super M4-plus* could be worked out.
Or the old EM-2 could be revived, using modern materials. The 700-800-yard effective range of that weapon would be nothing to sneeze at, nor should the possible effectiveness of it on soft body armor be overlooked. And it'd be a dandy in SAWs.
comparison table: British .280 caliber intermediate cartridge vs. most common modern military cartridges
ballistic data is estimated using Norma ballistic calculator and Sierra Bullets data on ballistic coefficients.
| |
5.56x45mm NATO |
7x43mm EM-2 |
7.6x39mm M43 |
7.62x51mm NATO |
| bullet weight |
4.01 g (62 gr) |
9.08 g (140 gr) |
7.9 g (122 gr) |
9.72 g (150 gr) |
| bullet velocity, at muzzle |
921 m/s |
745 m/s |
710 m/s |
860 m/s |
| bullet velocity, at 300 yards (273 meters) |
585 m/s |
570 m/s |
470 m/s |
674 m/s |
| bullet velocity, at 550 yards (500 meters) |
385 m/s |
450 m/s |
341 m/s |
516 m/s |
| bullet energy, at muzzle |
1700 J |
2519 J |
1991 J |
3594 J |
| bullet energy, at 300 yards (273 meters) |
686 J |
1475 J |
872 J |
2207 J |
| bullet energy, at 550 yards (500 meters) |
297 J |
919 J |
460 J |
1294 J |
--
I always liked the style of the EM-2. When it came time for the Brits to actually build their bullpup, though, did they ever cock it up. And the EM-2 looks like a human engineering disaster. How hot d'you think that steel receiver would get in the vicinity of the chamber? Burn skin after one mag, fry an egg after 250 rounds rapid fire?
I'm always leery of ballistic stats because they are missing important data. The two things most important in shooting people with guns are (1) can you hit the guy, and (2) will enough energy be transferred to him to significantly alter the course of his weekend? In ballistic terms you could state these as practical accuracy (which is really a product of the whole system, including the human interface engineering of the weapon and teh shooter himself) and terminal effect (which is not quantified in any generally agreed-upon way, efforts of the dentist and his various dental assistants notwithstanding).
If you don't hit your guy somewhere important, (2) is impossible. So (1) is the most critical measure, but nothing pertaining to it is in that table. To illustrate, the table you posted makes it look like the AK's M43 round has an edge on the 5.56 that improves with range. But in fact, at ranges beyond 200m, the short stock, crummy trigger, tiny sighting radius, crude sights, and high recoil-thrustline of the AK series makes hitting men problematic.
Not to mention the ballistic drop of the M43 which is getting pretty bad by 200m and approaching howitzer ballistic arcs (albeit scaled down) by 300.
Then, there is the issue of terminal effect. Give most guys who do a lot of shooting (people, not targets) a choice between the AK and the M16 series, and their choice will depend on whether we're talking about them shooting someone or someone shooting them.
By the way, if we go all the way back, isn't that to the FG-42? (What I love is army arsenals people copying the bolt design from that weapon, unaware that the designers of the FG [Haenel? Rheinmettal?] had cribbed their design from the (American) Lewis Gun of WWI.
d.o.l.
Criminal Number 18F