Mk38 Mod4 Gun Weapon System. MSI-Defense Systems

Army Recognition’s Navy News reports,

“The U.S. Navy is expanding its Mk 38 Mod 4 30mm gun inventory to give warships a lower-cost option for defeating drones and other small threats without relying immediately on expensive surface-to-air missiles. The latest production tranche adds 22 Mk 88 Mod 4 mounts, while current public procurement reporting places cumulative Mk 38 Mod 4 production orders at 55 mounts when earlier buys are included.”

The contract referred to here is actually for three years and is not limited to 22 systems.

This is good news, but how long before the Coast Guard sees 30mm Mk38 Mod4s? That will depend on Navy priorities and the build rate for these systems.

Navy priorities:

Right now, only one destroyer has 30mm Mk38 Mod4 mounts. It is the only current mod4 installation I know about, but there are certain to be more soon. It appears giving destroyers the Mk38 Mod 4 is their first priority, even though Destroyers have other more capable systems–Standard Missiles, ESSM, 5″ guns, Phalanx, and in some cases SeaRam. The Navy would like to conserve the more expensive weapons, but destroyer COs are unlikely to wait until the threat is in range of the Mk38 Mod4, about 3000 yards, before engaging. The Coast Guard does not have that problem

(Expect about 170 systems for destroyers.)

The Navy is not likely to stop with destroyers. We can expect the Mk38 Mod4 to go on Carriers and Big Deck Amphibs

(Expect 40 to 80 systems for CV/LHA/LHDs).

If they start arming MSC underway replenishment ships or the new LSMs with the Mod 4, it could add about one hundred more.

LCS and LPDs might get Mk38 Mod4s but they already have provision for a different type of 30mm mount the Mk46.

Coast Guard priorities:

The Navy no longer provides security to most US ports. The Coast Guard has always had a role in protecting ports, but with the creation of DHS it has become more prominent. The Ports, Waterways, and Coastal Security mission has become a major consideration in how the Coast Guard should be armed. Unmanned surface and air systems have emerged as a primary threat from terrorists or at the onset of hostilities.

The 30mm gun using air burst ammunition is now a primary hard kill system vs these threats. In addition to being a more effective defense, unlike the more common .50 caliber and 25mm, the 30mm air burst rounds can self destruct making collateral damage less likely. Since we may be firing inside a US port this becomes very important.

The Polar Security Cutters are slated to have two 30mm Mk38 Mod4s, but that is the only commitment so far. Hopefully it will also mean the Arctic Security Cutters will get at least one. That is not as well armed as I would like, Arctic Security Cutters should be armed like the OPCs, but it is a credible self defense capability.

The OPCs are still expected to get Mk38 Mod3s. A Mod4 mount would be better. Really I would like to see a SeaRAM in that position on the hangar and a couple of 30mm mod4 mounts sited elsewhere, but neither looks likely. At least the OPCs like the NSCs has the 57mm gun.

The NSCs could probably use a pair of Mod4 mounts, but the larger ships are less likely to be involved in force protection or defending an asset in a port than are the WPCs.

Webber class WPCs should have the highest priority in receiving a 30mm. Because of their large numbers and their normal patrol areas, they are the assets most likely to be called upon for a Ports, Waterways, and Coastal Security mission response vs UAS or USV. Larger ships are too limited in number and are more likely to be far from the ports or in maintenance when needed.

An Alternative:

Since the Mod 4 mounts are completely different from the earlier mounts, as they replace older, but still working, mounts on the destroyers it will be tempting to pass the old 25mm mounts to the Coast Guard rather than provide new Mod4 mounts, especially since it will be years before the Navy’s requirements are satisfied.

The Coast Guard has a long history of using Navy “hand-me-downs” and they were fine for peacetime law enforcement, but the 25mm is a far less capable against the most likely threats to Ports, Waterways, and Coastal Security. We need the most appropriate weapon and that is currently the 30mm. It is being adopted by the Army and Marine Corps as well as the Navy.

The Mk38 Mod2/3 is based on the Israeli Typhoon gun mount which can support weapons up to and including the 30mm Mk44.

• Counter-Air Plus w/ interchangeable 25/30mm cannon,
• APKWS
• Ready for 30mm Air Burst Munition/Proximity Fuzed Ammunition

When the Navy takes Mk38 Mod2/3 off destroyers they could have them refurbished with 30mm guns and maybe APKWS.

30mm is also significantly more effective against small craft than the 25mm (“nine times the damage to the hull and five times the damage inside the hull”).