For photos, see this DefenseMediaNetwork post.
It looks like the Coast Guard will be getting a new gun mount soon. Defense.gov reports a new $30,556,246 contract for Mk38 Mod3 gun mounts that includes “fiscal 2015 weapons procurement (Coast Guard) funding in the amount of $5,341,232 …(and)… fiscal 2014 weapons procurement (Coast Guard) funding in the amount of $152,781“.
The announcement does not make clear how many systems this will buy. The contract also includes systems for the Navy and at least one system for the Philippines. Assuming the Philippines is buying only one system, it appears the contract will buy 16-17 systems, one for the Philippines, one for the National Guard/Reserve, three for the Coast Guard, and eleven or twelve for the Navy, but in the more likely case, the Philippines is actually buying two systems, then the numbers may actually be double this, which would make sense if the Coast Guard buy was for six Webber class. An FY2012 Contract for 21 Mk38 Mod2s for $24.2M would seem to indicate they cost about $1.1M each. I would like to think that, since the program has matured, this larger buy might actually cost less per unit, so that this is actually a buy of 30 or more systems (probably 32-34), with six going to the Coast Guard, two to the Philippines, two to the National Guard and Reserve, and the rest to the Navy.
DefenseMediaNetwork reports the Mk38 Mod3 offers a number of improvements over the Mod2 currently being fitted to the Webber class, including more ready ammunition on the mount (500 rounds vice 165), a coaxial .50 cal. gun (there was already a plan (pdf) to add a coaxial 7.62mm to the Mod2 version), higher elevation (75 degrees vice 40), better weather protection and serviceability, and the ability to simultaneously track up to three targets. There are also improvements to the search function of the ElectroOptic sensor that should make the system more useful in peacetime roles. They also report that BAE and Israeli manufacturer, Rafael, are considering adding the “Advanced Precision Kill Weapon System” APKWSII guided 70mm rocket system to the mount. In fact Israeli versions of this system already support surface to surface and surface to air missiles.
Most photos of the Mk38 Mod3, like the one above feature a 30mm gun which is an option, but it appears, from the language in the announcement, that these mounts will use the 25mm. I believe there is even a 40mm option. The Navy may be recycling existing 25mm guns, moving them to the new mount. Personally I would have preferred the larger caliber weapon, for its ability to take on larger surface targets. The 30mm would have almost as many rounds on the mount (420 vs 500), would be more accurate, have a greater effective range (3000 vs 2500 meters), and provide greater penetration.
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You can do more with a 30mm round with fuses etc.
This would be the 30mm gun. https://en.wikipedia.org/wiki/Mk44_Bushmaster_II
The only “smart fuse I am aware of right now would be the air-burst ammunition. http://www.globalsecurity.org/military/systems/munitions/30mm.htm
The Mk44 30mm is the same gun (in a different mount) the Navy has chosen to replace the 57mm on the DDG1000 class.
https://chuckhillscgblog.net/2014/10/13/time-to-ditch-the-57mm/
But then there is this. Application of a guidance system to 57mm shells. http://www.navyrecognition.com/index.php/news/naval-exhibitions/sea-air-space-2015/2612-bae-systems-unveils-the-orka-one-shot-one-kill-round-for-57mm-gun-at-sea-air-space-2015.html
The larger the round the more you can do with it, the smarter you can make it, and the more worthwhile the improvements are.
Combat history: The Brownwater Navy had many weapons which were dual-mounted similar to coaxial. PBRs had a 60mm mortar & M60 7.62 MG over and under on after mount as an option. The Swift boats had an 81mm mortar and .50 HMG combo aft. The PTFs had that mount also I believe? The MRF heavy boats had variations of the scheme. The RVN river boats used some of those.
The new Mk 38 MOD 3 is a good move, the coaxial missile is something Bob Stoner has been recommending for YEARS now (specifically the Spike ER).
IF the USN is reluctant to put heavier weapons on warboats (like the Patria AMOS and NEMO 120mm auto mortars) then the above solution will do for NOW~
BUT I am sure that Sailors and Marines landing parties would LIKE to have some indirect fire gun support with throw weight!
Not going to be seeing any LCS in close~ The brownwater and to a large extent greenwater will be the domain of the USN’s rather limited number of small combatants like PCs and MK VI PBs for some time to come.
The Coast Guard invented the over/under mount for operational use. The first was designed by Lt. John Mel about 1906 with a Lyle gun mounted above the 6-pounder RF gun.
About 1935, the Coast Guard developed the 30-06 Lewis MG mount on the 1-pounders that later adapted for the 3″/23 on merchant vessels in WWII. The Coast Guard then developed the .50 caliber/81mm piggyback. (The USN contracted with the Coast Guard Yard to build the adapters. I never saw the 60mm/M60 arrangement. The 60mm mortar on a boat was all but useless.
Given the budget situation I’m not surprised it appears the 25mm is sticking around for the moment. But on the positive side, having the Mod3 already on-deck makes it easier to transition to 30mm (or bigger) as the hand-me-down guns wear out.
On the LCS subject, I wonder what the Mod3 will mean for the Mk46 mount going forward. With the EFV long dead the only thing the latter is compatible with is itself, and other than “we already have it” I’m not sure what it has over the Mod3.
I was wondering the same thing about the Mk46 mount. While having man in the mount and a dual ammunition feed, might be considered advantages. It no longer seems to have significant advantages and has some disadvantages. Looks like the Mod3 has greater AAW capability and maybe better sensors.
A gunners opinion (not me) is that while the 25mm round has better characteristics the 30mm is almost as good. With the Mk48 mount being installed on USN warships, I highly doubt the Navy will change gears?
Remember these are not the only weapon system onboard. Layers you know~
But on the Webber class they are the primary and in a sense the only weapons system (yes I know they have M2 .50 cals. too).
Why is the Coast Guard buying its own systems? Are these not Navy owned and supported?
Don’t know if they were really saying that that was actually Coast Guard money or simply that the systems are being bought for the Coast Guard. Anyone know?
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Luke S. pointed me to a study of secondary weapons for the Offshore Patrol Cutter. https://chuckhillscgblog.net/2016/05/21/webber-class-wpc-homeports/
While some results have been redacted, it is apparent that the 30mm does in fact have a longer effective range than the 25mm as expected. 18 to 29% greater based on average kill range.
They would also have greater penetrating power against damage resistant targets.
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New contract award, https://www.defense.gov/News/Contracts/Contract-View/Article/1330165/
“BAE Systems Land and Armaments LP, Armament Systems Division, Louisville, Kentucky, is being awarded a $32,787,486 firm-fixed-price supply contract for fiscal 2017 through 2020 production of the MK 38 MOD 3 machine gun system (MGS) and associated spares. This contract includes options which, if exercised, would bring the cumulative value of this contract to $121,518,062. Work will be performed in Haifa, Israel (67 percent); and Louisville, Kentucky (33 percent), and is expected to be completed by April 2019. Fiscal 2017 weapons procurement (Navy) $26,879,041; fiscal 2015 National Guard and Reserve Equipment Appropriation $3,196,511 funds; fiscal 2017 weapons procurement (USCG) $2,711,934 will be obligated at the time of award, of which $3,196,511 will expire at the end of the current fiscal year. This contract was not competitively procured in accordance with Federal Acquisition Regulation 6.302-1(a)(2) – only one responsible source and no other supplies or services will satisfy agency requirements. The Naval Surface Warfare Center, Indian Head Explosive Ordnance Disposal Technology Indian Head, Maryland, is the contracting activity (N00174-17-C-0022).”
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