M16A5 Concept: A Modular, Multi-Caliber Rifle for Future Infantry Warfighters?

by Jim Jensen

Assault Rifle/Carbine with interchangeable bolts, barrels and magazine wells can shoot 5.56mm, 7.62mm Russian, and 7.62mm NATO bullets

Iraq: ”Ping” “ping” “ping” an U.S. Army light infantry Soldier firing from the top cargo hatch of a BAE Systems M113 APC (Armored Personnel Carrier)/armored vehicle is placing well-aimed 5.56mm (5.56x45mm/.223 Remington) M16A2/A4 rifle shots on an Iraqi rebel placing an IED into a road, but he is not going down. Instead, he has rolled over and is firing back. The “pinging” sounds are not from American bullets. They’re from the insurgent’s 7.62mmx39mm rounds bouncing off the vehicle’s hull. As this is going down, one of his buddies is now preparing to launch a rocket propelled grenade (RPG) at the American soldiers.

Afghanistan: A 5-man team of Taliban rebels are spotted at 600 meters away standing by a village mud building. 82nd Airborne paratroopers open fire with…

their 16-inch-barreled M4/M4A1 carbines. Their 62-grain rounds fall short of the target, and simply create dust clouds as the now angry rebels spread out and hide under cover. The paras will now have to close in to regain line of sight (LOS) at a closer range, and some of them may get wounded or killed in the process. If they call for air support–an A-10 Thunderbolt II a.k.a. “Warthog” air strike, for instance–innocent civilians will get killed and their relatives will join the rebellion.

Iran: The coalition troops’ tracked armored spearheads were nearing the capital city, Tehran faster than their Jessica Lynch-style resupply columns in wheeled trucks could keep up. Unexpectedly, a U.S. resupply column of fuel and ammo is mired in loose sand and is hopelessly stuck,. No one knows how to get the wheels to stop spinning in the sand. As they form a hasty 360-degree perimeter around themselves, Iranian prop-driven trainer-attack planes appear and start strafing and rocketing the trucks which begin exploding. The support troops’ return fire is uncoordinated, and the Iranians only fly off when they run out of ordnance. Over 100 American Soldiers are now stranded in the middle of the desert without water, and it’s too far to walk back to the FOB (Forward Operating Base). An Iranian mechanized patrol spots the column of smoke and flames, and fires on the hapless troops. All the Americans know how to do is sit there and return fire as their ammo runs low.

Forward at the spearheads, the news that they will have no resupply causes them to stop far short of their objective. Their fuel is too low to continue and they only have 1 basic load of ammo left. They have killed a lot of Iranians to get this far, but now wish they had collected up their guns and ammo instead of leaving them. Iranian mechanized forces and attack planes are reported inbound.

Why are U.S. Forces outgunned today?

Today’s gunslinger-obsessed U.S. Army and Marine Corps have long ignored the need to have high-explosives-effect weapons (like the enemy’s RPG-7/RPG-7Vs) in their hands in enough quantity to dominate a close range (under 1, 000 meters) fight. However, this denial extends to even their actual gunslinging, itself, which now is deficient against the enemy’s Kalashnikovs (AKMs/AK-47s and AK-74s). Its high time that we solve these problems of Lethality, Range, Training and Resupply by replacing the current M16/M4 family with the ultimate “M16A5” that would be modular so that ANY type of cartridge can be shot as needed to prevail on the non-linear battlefield.

This is not a fantasy, MGI Industries, Inc. a.k.a. MGI Military now makes just such a modular/multi-caliber rifle/carbine system called the "Hydra" that can shoot virtually any current combat-relevant caliber of cartridge by just quick-changing the barrel, bolt and magazine well. With a MGI Hydra-type system, no U.S. warfighter need be out-gunned any longer on the NLB (Non-Linear Battlefield). A requirement needs to be drawn up for the M16A5 albeit with a gas piston system to keep carbon out of the firing chamber and a “shoot-off” conducted. The winner needs to be placed into production immediately using the industrial base of FN’s plant in South Carolina and Colt in Connecticut.

Enhanced Lethality

There are a number of small arms experts who believe that if the United States military sticks with the 5.56mm (5.56x45mm) round for its infantry rifles (assault rifles), we should revert back to a 55-grain bullet (a la M193) fired out of a barrel with a 1-in14” rate of twist (the AR-15/M16’s original twist rate when it was first developed and produced) for urban warfare/urban combat. They believe it would be a more effective man-stopper in the majority of urban warfare/urban combat (closed terrain) engagements since the very unstable bullet tends to go into yaw very quickly inside the human target, provided the bullet is accurate enough to hit the target. Since the majority of urban combat takes place at ranges within approx. 100 meters, they feel that a 55-grain round would easily exhibit enough combat accuracy at this range, and even out to distances well past this range–even out of a 1-in14” twist barrel—at least out of an M16’s 20-inch barrel.

The pro-55-grain/1-in-14”-crowd believes that the currently-employed 5.56mm “heavy” (62-grain M855/SS109) round is over-stabilized out of a 1-in-7” twist barrel, which is the current U.S. military spec. This results in the bullet’s disturbing tendency to pass right through the flesh of lean (i.e. skinny) enemy targets like Afghani fighters and Iraqi insurgents (and the Somali fighters before them), thus failing to stop them. That being said, the “heavy” 5.56mm bullet (62gr) is perhaps the better choice for longer-range desert fighting (open terrain fighting) against foes driving up in pick-up trucks (vehicle penetration) or hiding behind some cover, as during the march to Baghdad.

Therefore, we propose that the M16A5 Modular kit comes with a 5.56mm “light” barrel and 55-grain ammunition be produced for troops fighting in closed terrain, marked by a YELLOW tip. A 5.56mm “heavy” barrel would be included for shooting GREEN tip 62-grain bullets for fighting in open terrains. Same cartridge, just an additional bullet-weight option that requires a spare barrel. A weapon like the MGI Hydra QCB (Quick Change Barrel) rifle/carbine (a.k.a. MGI Hydra QCB Weapon System) would allow the operator to swap barrels in seconds.

Extended Range

In the mountains, you are faced with a combination of open terrain looking across to high ground and closed terrain if you get up into it amongst rocks and caves. For long-range engagements approaching a village, or after sighting a foe through an optic (optical sight or scope), even the heavy 5.56mm bullet lacks adequate range/power, and 7.62mmx51mm NATO is required. Having a 7.62mm x 51mm NATO (.308) barrel, bolt carrier group (bolt and bolt carrier), and magazine well in the M16A5 battle kit will enable commanders to designate marksmen or convert entire fireteams and squads to 7.62mmx51mm as necessary to prevail in combat.

Improved Training

One of the beauties of a MGI Hydra QCB-style M16A5 modular/multi-caliber system is that it can also be configured to shoot Simunition force-on-force training ammo (colored-soap bullets) by a simple bolt carrier group and barrel change, so every Soldier in the army at recruit training (IET) can be taught fire & maneuver, and not just laying on the ground and returning fire since defeat of the enemy often requires moving to get a LOS (Line of Sight) that will finish the enemy off by killing or wounding him.

Resupply

America does not draft millions of men to create 100 divisions of ground forces able to push all enemies to our front. We only have a small Army and Marine Corps. If we go to take-down an enemy nation-state, spearheads in tracked armored columns will have to press ahead and hope their Jessica Lynch-type supply units in trucks without adequate armor or weaponry can get ammo, fuel, water and food to them. The fact is that if the enemy lets our spearheads pass and attacks our resupply columns instead, we can actually lose the war for a lack of bullets. The M16A5 kit, by including a barrel, bolt carrier group, and mag well for shooting enemy 7.62mmx39mm Russian ammo from their rotate-and-click AKM magazines will enable spearhead units to collect enemy ammo as they go via “Collection” squads. They can then switch to enemy (7.62x39mm) ammo when their 5.56x45mm or 7.62x51mm ammo runs out, and “give it back to them” to reach their objectives. In other words, we can out-guerrilla the guerrilla.

Now let’s return to our 3 cliff-hanger situations and see what would have happened had they been equipped with MGI Hydra-type M16A5s, caliber change kits, and the most effective cartridge(s) for the job.

Iraq: With M16A5s in 5.56mm “light” configuration…”thwack” “thwack” “thwack”, an Army Soldier firing from the top cargo hatch of a M113 APC/armored vehicle is placing well-aimed 5.56mm M16A2/A4 rifle fire into an Iraqi rebel who’s in the process of placing an IED into a road. The bullets yaw through his body. He falls down and doesn’t get back up. A buddy is now getting a rocket propelled grenade (RPG) to launch, but 3 shots drop him. The American Soldier with his buddy, runs out to the bodies and recovers their explosives, AKM and RPG launcher, their web gear with ammo in magazines, which is tossed into the back of their COLLECTION trailer. “Pay Back” will be paid for by their own ammo.

Afghanistan: With M16A5s in 7.62mm NATO configuration….a 5-man team of Taliban rebels are spotted at 600 meters away standing by a village mud building…82nd Airborne paratroopers open fire with their 20 inch barrel folding-stock M16A5 carbines and their 180 grain bullets take down the surprised rebels and finish off the one trying to hide behind a donkey cart…the paras can close in to recover their bodies, weapons and ammo for intelligence on where their comrades might be…no innocent civilians are harmed and they see what will happen to them if they join the rebellion…

Iran: With M16A5 trained and equipped troops….the coalition troops’ tracked armored spearheads were nearing the capital city, Tehran faster than their Jessica Lynch style resupply columns in wheeled trucks could keep up. Unexpectedly, a U.S. resupply column of fuel and ammo is mired in loose sand and is hopelessly stuck, no one knows how to get the wheels to stop spinning in the sand. As they form a hasty 360 degree perimeter around themselves, Iranian prop-driven trainer/attack planes appear and start strafing and rocketing the trucks which begin exploding. The support troops’ return a wall of fire shooting down two of the planes so they fly off. Several trucks are still undamaged but stuck. Over 100 Soldiers are not stranded in the middle of the desert and have plenty of water IF they can get unstuck to proceed forward to link up with the spearheads to resupply them. An Iranian mechanized patrol spots the column of smoke and flames and takes the hardy troops under fire. The Americans return fire and begin to fire & move on the Iraqi dismounts, killing several before the survivors hop into their BMP and flee the scene….the weapons and ammo from the dead are recovered to bolster their warfighting means…an American AY-65 Vigilante armored crop duster organic to every Army brigade (by being towed on a trailer instead of needing a fixed air base) responding to the threat of the Iranian prop planes spots the stranded column and lands. They tell the pilot and observer that they are stuck, so they take-off and relay a request for a tracked M88 wrecker with some AM-2 pierced aluminum planking to come to them to un-mire them as a sand channel. It may work or it may not; resupply should be tracked just like the fighting spearheads.

Forward at the spearheads, the news that they will have no resupply causes them concern but they decide to proceed to the objective. Their fuel is too low to continue and they only have 1 basic load of ammo left but they have killed a lot of Iranians to get this and have collected up their guns and ammo so really they have two basic loads of ammo…Iranian mechanized forces and attack planes are reported inbound…the Iranian tanks are destroyed and the attack planes shot down or warded off. They are nearly out of U.S. machine gun ammo gunning down the suicidal waves of Iranian infantry and switch their M16A5s to shoot captured 7.62mm x 39 Russian ammo. What 7.62mm x 51mm NATO they have is consolidated into the M1/M2 co-ax medium machine guns for firing when buttoned up. The mech infantry and combat engineers will shoot enemy 7.62mm x 39mm from their M16A5s from the top cargo hatches of their medium M2 Bradley IFV (Infantry Fighting Vehicle) and light M113 tracks. The spearheads stop just short of the capital city as Army Joint Cargo Aircraft fixed-wing transports and S-64 Skycrane helicopters land on a nearby road and offload 500 gallon fuel bladders and a 5, 000 gallon “fuel pod” filling station to resupply the thirsty tanks.

Conclusion

When U.S. warfighters (soldiers and Marines) are out-gunned, there are unintended consequences that flow from this weakness. Consider the Jessica Lynch debacle: Soldiers are killed, wounded and captured. Or, just consider how the elusive Taliban and al-Qaeda terrorists keep popping up in Afghanistan and rebels in Iraq keep blowing up Americans along main supply routes. When we get the drop on the enemy, we have to drop him–for good. The modular/multi-caliber M16A5 system will end the endless 5.56mm vs. 7.62mm vs. 6.8mm (6.8x43mm SPC a.k.a. 6.8 Remington SPC) cartridge controversies that end in no positive, tangible improvements because for the first time we can act to make the needed changes. No longer will we be stuck with a cartridge and the bureaucrat’s excuses that we cannot replace what we got. What we’ve got now—a modular/multi-caliber rifle/carbine with true quick-change-barrel system–can now adapt. This is what we need to prevail on today’s non-linear battlefield–and we needed it yesterday.

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