Is it time for the Military to look towards a new rifle round?

2015-08-13T22:49:03-04:00

Everyone knows that the 5.56 round isn't ideal for combat, but due to the geneva convention, seems like we may be stuck with it.
But what round do you think we should be looking at? IMO, .300blk would be a top choice. Let's look at why.

Its purpose is to achieve ballistics similar to the 7.62×39mm Soviet cartridge in an AR-15 platform while using standard AR-15 magazines at their normal capacity.

While 5.56×45mm NATO has enjoyed widespread acceptance in military circles, the nature of the missions encountered by some special operations groups often demand a round that not only provides better performance than that available in the high-energy standard velocity rounds, but one that can offer subsonic performance greater than the current standard 9mm Luger round.

The 7.62 Soviet's cartridge taper prevented reliable feeding in AR magazines and created wear on the bolt. From the 14.5 in (370 mm) of the M4 Carbine, the M855 5.56×45mm round has an effective point target range of 500 meters. The bullet has significant drop, drift, and energy loss at that distance. From a 16 in (410 mm) barrel, a 125 gr (8.1 g) 300 BLK round has a lower velocity and similar bullet drop and drift at shorter distances. However, it has the same amount of energy at 700 meters that the M855 has at 500 meters. In terms of hit probability, the Blackout has an effective range of 460 meters. From a 9 in (230 mm) barrel, the 125 gr BLK round has the same muzzle energy as the M855 from the M4, and 5 percent more energy at 440 meters. In comparison with 7.62×39mm rounds, 300 BLK rounds with varying loads have a better ballistic coefficient and more energy out of similar length barrels. 300 BLK rounds have "barrier blind" performance, being capable of penetration through several inches of different hard targets. The .30 caliber cartridge has an 89.1 percent increase in frontal bullet area over the 5.56×45mm, and so leaves a large wound cavity in soft targets. It also penetrates deeper and initially yaws faster. 300 BLK rounds are effective out of barrels as short as 4.5 in (110 mm). Weapons chambered for the round can be as light, compact, and quiet when suppressed as submachine guns like the 9 mm Parabellum MP5 and 4.6×30mm MP7 while having more energy and accuracy at longer range.

The 6.8 SPC has a more difficult conversion because it was designed around the .30 Remington cartridge, requiring a different bolt and decreasing standard magazine capacity. The 300 BLK was made specifically for ease of conversion, so the standard bolt will work and a magazine can be used to its full capacity, so the only change needed is the barrel.

Response by SSgt Alex Robinson made Aug 13 at 2015 11:15 PM

2015-08-13T23:15:11-04:00

Something with even better stopping power would be great

Response by CSM Charles Hayden made Aug 13 at 2015 11:17 PM

2015-08-13T23:17:08-04:00

SPC Dave St. Andrew, The Army Times reports of a hollow point bullet being considered.

When the Army cannot find a reliable, injury causing, effective replacement for the 1911 Pistol, how will they ever determine the effectiveness of a new rifle round?

Response by SA Harold Hansmann made Aug 13 at 2015 11:24 PM

2015-08-13T23:24:16-04:00

Why not a .243 with 100 grain bullet?
It's equivalent to a 6mm, flat trajectory, long range, and it has a variety of different type of bullets.
It has no problems dropping a deer which is equivalent to a human in weight. I would use mine to hunt moose.
As a Kevlar round it should be small enough to pierce a flack jacket.

Response by SSgt Private RallyPoint Member made Aug 13 at 2015 11:31 PM

2015-08-13T23:31:24-04:00

http://www.bing.com/images/search?q=5.56+Trajectory+Chart&view=detailv2&&id=8967289A6303AF523E0625ED88A0A97D075F0063&selectedIndex=4&ccid=tcRKm1Gz&simid= [login to see] 91423202&thid=JN.ss09Z8UtE595mEs2hKqbaA&ajaxhist=0

This ballistics chart should help show why I don't think the .300 blackout is worth the hype

Response by LCDR Private RallyPoint Member made Aug 13 at 2015 11:37 PM

2015-08-13T23:37:11-04:00

You can see just from the vast variety of responses the initial problem. Changing rounds first of all won't make everyone happy. Second every single weapon in the inventory would essentially need to be changed at the same time or there would be risk of having the wrong rounds for the weapon. I don't see it realistically happening any time soon.

Response by COL Charles Williams made Aug 14 at 2015 12:14 AM

2015-08-14T00:14:31-04:00

I did not know everyone knew that? I spent some time in TRADOC in doing DOTMLPF, and while there are complaints about everything, there are also many positive AAR comments and LLs. 5.56 and 7.62 are just fine. I spent a long time in the Army, and folks were always complaining and second guessing the M-16, M16-A1, A2, A3, M-4... I used them all, and I believe they did just fine. Since we have a need, for logistics reasons, to limit the number of options... if 5.56 is not the answer, then 7.62 (x51) is the best answer if a changed is needed. But, the M-4 is just fine, in my limited view.

Response by TSgt David L. made Aug 14 at 2015 10:02 AM

2015-08-14T10:02:53-04:00

The ballistics for the .300blk (only slightly better than AK type ballistics) are inferior to the 7.62mm NATO round, IMO. If, and I think the option should be available for most missions, we make the switch the AR-10 type 7.62mm platform is the way to go. You get the bonus of a round already in the inventory and, although the action is a bit longer, the AR controls will require no special training and with the exception of having different ballistics, would be virtually un-noticeable.

That said, I like both the 6.5mm (max range 1000yds, MV2,400fps and 6.8mm (max range 1000yd, MV 2,775fps) choices. Again, no real noticeable changes in the AR style controls so the change-over would be virtually unnoticeable. Just my opinion from having experience with all the above platforms.

Response by MSgt Private RallyPoint Member made Aug 14 at 2015 1:34 PM

2015-08-14T13:34:37-04:00

That's a pretty powerful statement. Not sure who exactly the "everyone" is that you refer to. Many experts (weapons troops, field tests, medical examiners, Forensic specialists, etc) would disagree with you.
Are suggesting we go with a less accurate round then the 5.56mm? On top of that you are quoting the performance of the 125 gr .300BLK match grade round not the 115 gr standard round that would be issued. So how much less accuracy are we going to be dealing with once we start talking standard rounds?
Now I will grant you that its lack of stability compares favorably with the old M193. So you get projectiles that tumble and fall apart after entering a body.

Response by SSG Mathew Ada made Aug 16 at 2015 8:14 PM

2015-08-16T20:14:44-04:00

Honestly, when you look at the ballistics of the round in comparison to other rounds of higher caliber, the difference will always favor the round that requires more energy to move. The FM for the 5.56x45 may say that the maximum range for a point target is 500m. When in fact the killing power of the round isn't effected until a little after 800m. Thus the actual point target range can be pushed to 800m on a point target with a good marksman. Also, look at the distribution of the round, its carry weight and cost value. In order to mass produce rounds of the calibers in which you suggested, the government would have to phase out current weapons systems using the previous round and integrate the newer one. This means costs of logistics and administration. The sheer scale to eliminate the primary ammunition platform for all dismounted personal is staggering. Also, take into consideration that the military has looked into various other rounds as well. While a 7.62x51 may have more knockdown power, the round also weighs 2 times that of a 5.56x45. The average combat load for a person is 210 rounds of 5.56x45, weighing roughly 21lbs with magazines. 210 rounds of 7.62x51 is roughly 42lbs not including magazines. Think past the ballistics, and think about overall effectiveness. More "knockdown" power equals more weight. If shooting someone in the thoracic cavity doesn't put them down, remove the base (pelvic region) and share the love to the face. Shoot until your opponent changes form.

Response by SGM Bill Frazer made Apr 3 at 2018 10:10 AM

2018-04-03T10:10:33-04:00

I loved the 7.62- better range, more punch, less deflection.