Guns for the Offshore Patrol Cutters

In the interest of saving a big chunk of money, I think the Coast Guard and Navy should reconsider the proposed fitting of the 57 mm gun to the new Offshore Patrol Cutter (OPC), and perhaps recycle existing Oto Melara 76mm Mk 75s instead.

If the Navy is going the stop supporting the Mk 75, we probably have no choice, but the 76mm is one of the most widely used weapons in the world. New developments including guided munitions and high velocity discarding sabot rounds are keeping it competitive.

STRALES system Oto Melara Munition Gives Naval Guns Low-Tech, ‘Nonlethal’ Precision

The two systems are very similar in weight and range, with the 76mm having a slight edge in range. The 57mm has a higher rate of fire, but this is balanced by the greater weight of the 76mm projectile.

It may not save the CG a lot in acquisition because, if it is like past programs, the Navy is buying the gun, but the Country has to pay for it, and the CG might benefit in having to retrain fewer people to maintain the weapons.

I think the choice of which is best boils down to what you think the critical threat we need to address is. If it is airplanes and cruise missiles or huge swarms of Iranian speedboats, the 57 mm might be better, but if you think you might have to sink a ship or hit targets ashore, then the 76 is probably better. Frankly I think the latter is more likely. For that reason I would actually prefer we mounted a 5″ Mk 45, but I don’t think that is going to happen.

98 thoughts on “Guns for the Offshore Patrol Cutters

  1. That gun was and is a horrifically overcomplicated piece of crap! We had 3 gunners mates put more TLC into that thing working 7 hours a day for a week, and then during REFTRA, it crapped out after only 2 shots. I got to see the 57 up close, and it is a VERY modern yet simplistic gun system it reminds you a little of some of the deck AA armaments of WWII ships. We never needed or wanted the ability to fire so many huge shells like the 76mm at such a rate of fire. Good riddance to that thing.

  2. First of all 76mm is not huge. It is relatively small and originally conceived for AA work. The 5″/38 had more moving parts and it worked fine. The Coast Guard had its relative 40mm for decades. Yep, it is a simple system. Then again perhaps today's GMs need simple. The 57mm is not that “modern” and it is has direct kinship of those WWII weapons. It has been around since 1981 in various forms. However, look at the size vessels it is being used around the world and then look at the Coast Guard. I also found it funny that it is possibly the first gun the Coast Guard has had with a foreskin. This is an internet remark about it, “The stealth variant has a reduced radar profile, in part by hiding the gun barrel when it is not firing.”

  3. First of all 76mm is not huge. It is relatively small and originally conceived for AA work. The 5″/38 had more moving parts and it worked fine. The Coast Guard had its relative 40mm for decades. Yep, it is a simple system. Then again perhaps today's GMs need simple. The 57mm is not that “modern” and it is has direct kinship of those WWII weapons. It has been around since 1981 in various forms. However, look at the size vessels it is being used around the world and then look at the Coast Guard. I also found it funny that it is possibly the first gun the Coast Guard has had with a foreskin. This is an internet remark about it, “The stealth variant has a reduced radar profile, in part by hiding the gun barrel when it is not firing.”

  4. The discussion over whether the CG needs a gun like the 5″ keeps popping up on various discussion boards periodically. The naysayers usually point out the CG’s missions have changed and we would never be called upon for NGFS again. Some point out that if we need help we can rely on the Navy or AF to come to our aid. That inplies we are not operating independently and that the Navy or AF just happens to have something in the area that isn’t all ready busy.

    Many folks thought we didn’t need a 5″ felt after WW II……and then Vietnam came calling.

    As Bill has pointed out, there were plenty of aircraft and Navy vessels in the area, but we still ended up expending a LOT of 5″ ammo.

    In my 10 years I was on 5 WHEC”S. All had 5″ and I became intimately familiar with the. Once yu get past the perpetual hydraulic leaks they are really a simple weapon to maintain.

    From what I have read on a variety of web discussions, it does seem the GM’s of today are perhaps not as well trained on the weapon systems as we were years ago. Apparently it is not uncommon to call on a contractor to come sort out any problems. That concerns me a great deal, as contractor may not be available when you are a thousand miles away from port.

    I would hope that the CG would somehow, someway, figure out that they may still need to perform military missions, that they still may need to be able to defend against submarines, and get back to being a military organization.

    • Is the perpetual hydraulic leak in reference to the oto melara 76mm gun slewing system? If yes, what is the preferred maintenance and maintenance cycle to minimize the leak?

  5. Well, this particular blog is about the OPC and prospective guns for them. That said, my opinion is that in post 9/11 world, CG should be focused on border-protection “liquid-style”. Even in time of war (especially the low-intensity/counter insurgency type war which seems to be the main problem nowadays), this border-protection mission should be paramount for the USCG. (Yes, there will be units and assets that deploy, but the vast majority of OPCs should stay local and protect our home waters.)

    Therefore, as far as GUNS are concerned, the CG’s wartime mission will be extremely similar to the peacetime LE-type Interdiction missions the CG already performs. (There may be changes needed in ASW capability and speed to pursue contacts, but this is question about GUNS and the OPC, so that’s what I’m sticking to.) A stabilized 25mm (Mk38 Mod2) will handle surface targets from 100m to 1000m and the 57mm Mk110 Mod0 will handle things from 250m out to 9km or so.

    When the 57mm Mk110 was adopted, I questioned what was going on with the great shrinking caliber situation as well, but after learning of it’s capabilities, I’ve grown much fonder of it. Fairly light weight, high-capacity magazine system with good reloading for continuous fire, simple mechanics for less to go wrong and easier to maintain and repair, very high-tech programmable ammunition with 6 fuze settings, and anti-vessel and anti-air capability make it quite a good weapon system for the CG. Another feature that is downplayed or not mentioned is that with it’s programmable proximity fuze and rate of fire, it functions as a CIWS/point-defense system.

    So, with a mixture of the 57mm and 25mm, I think an OPC would not be weight overloaded for a small ship, while having excellent capabilities for both peace-time and war-time operations (as long as command does not put them someplace they won’t belong.

    Now, if you feel the OPC should be deployed someplace, such as the Persian Gulf, during an all-out war setting, we’re going to have a lot more to worry about than whether the deck gun’s maximum caliber is 57mm, 76mm, or 127mm, such as it’s RCS, SLQ32 system, RBOC, RAM, CIWS, and whether it has any other weapons/capabilities to make it useful to the TF commander.

  6. This is some caveat, “as long as command does not put them someplace they won’t belong.”

    While we are supposing, it could that the “border protection” may be the wrong place. Personally, I’d like to see how this gun could handle a target at 1000m. Even with stabilization, it is still human controlled. Besides, that isn’t such a great range. I’ve hit live targets at 900 yards with a hard mounted .50 caliber from a bouncing boat.

    In a LE role, I doubt you’ll see the VT round used. It looks good on You Tube but would the Coast Guard actually use it? That is where war fighting skills, culture and practice come to play.

  7. I was doing some reading today on detainees in the current conflict. On paragraph struck me as applicable to the question about arming cutters within the scope of assumed operations.

    “To describe the complexity of conducting modern military operations in an urban environment, US Marine Corps General Charles C. Krulak used the metaphor of a “three-block war,” an environment wherein soldiers or marines simultaneously fight a high-intensity conflict in one block, suppress a simmering insurgency in another block, and facilitate humanitarian aid in a contiguous third block. Military forces conducting operations must anticipate encountering an array of friendly, hostile, and neutral persons within the three blocks.” (From “Six Floors” of Detainee Operations in the Post-9/11World
    THOMAS E. AYRES, Parameters, Vol. 35, 2005).

    Bill Smith’s use of the word “liquid” comes into mind here. The Coast Guard could be in the ‘three-block’ position in a hurry–even in its homeland operations.

  8. From one Bill to another… 🙂

    Yes, that caveat is both grandiose and onerous simultaneously.

    Here’s another point with which to stir the pot: When past wars broke out which our country was under-prepared for, the military (including CG) fought with what they had before the war started, sometimes for quite awhile into the new war… That argues against my own point, in that, it will be unlikely or at least slow and difficult to actually get additional systems added to any “under-equipped” cutter that is being sent into harm’s way. (Therefore, we should equip them as much as possible now…)

    Without all of that extra armament (which is how we are doing things, regardless of what we pontificate about here) it is another argument for leaving them to do what they should do (Guard CONUS), but I agree with your skepticism about my predicate of having smart Natl. Cmd. Authorities…

    All of this does give me mixed feelings about the whole issue, but in my mind, the proper use of this class of CG ships (WMEC/OPC) in an old-fashioned, declared, full-scale, open-warfare situation is coastal protection around CONUS.

    Now, the NDC should be equipped with everything a frigate or ASW destroyer should be, and it should be utilized for cooperative missions with the Navy.

  9. Forgot to mention, Bill, I agree with you on the VT fuze. I think the primary use of the VT on a CG vessel is for the point-defense/CIWS role. For LE, I believe the regular-capacity HE with delay fuze into the steering gear/engine room would be most likely.

    • One thing I forgot to mention earlier. Long ago, I was in the bullet buying business for the Coast Guard. Although the Navy does supply major caliber numbers, the Coast Guard has to buy what it uses for training and etc. This means that historically, the Coast Guard has always gone on the cheap side.

      When the LE game began, I wanted all .50 caliber to be AP, API, INC, TR rounds. The Coast Guard bought Ball — it was cheaper. The same will be for the 57mm. I bet that somewhere they’ll use non-explosive BL&P for actual LE shoots. It is safer and cheaper.

      I once dissuaded a CO from using the 5″/38 BL&P round on an Eastern rig side trawler. He wanted the “rudder” taken out. I told him, if necessary, the .50 caliber was as effective on this class and much cheaper. At the time .50 caliber as about $4.00 a round and the 5″ $150. Besides, at first, he did not understand what a 55lb projection moving at 2700 fps would do to one of these rickety boats.

      In 1819, the Treasury Department sent two cutters to the Gulf of Mexico to chase down pirates. These two, Louisiana and Alabama, were both armed with two 3-pounders and some small arms. That was it. Even after a couple engagements, and with the Navy’s approval (Commodore Patterson) to give them one, the 9-pound pivot gun was not installed. This was a known situation of hostility and still they went under armed.

      • Well, unless the CG goes and asks BAE or Bofors to make a cheaper round for the Mk110, it was my understanding that there’s only a few rounds for that gun, and they’re all HE of some sort. If my memory serves me correctly, there was a Hi-Cap HE round which had greater range and payload, as well as the same HE round that has always been used. The main difference with the new round is the fuzing and pre-fragmented jacket (but I think it’s the same size, weight, and shape as the old HE round), so I’m not sure there’d be a huge difference in costs.

        Then, of course, the question will become, against a small boat contact, at what range will the 57 be effective as far as carefully-placed rounds go, and how does that fit into the rules of engagement? Then, there’s the question of by the time the ship is at that range, will the 25mm do the job just as well? Lots of questions still unanswered.

      • GD-OTS Canada (formally SNC) makes 57 MM ammunition, as well as NAMMO. The two rounds available through BAE/Bofors, Mk 295- 3PHE & Mk 296 – TP, have been tested & certified for use in US 57mm naval gun mounts. There are other types of 57mm ammunition available from other vendors… The Hi-Cap HE round you’re referring to is the High Capacity Extended Range (HCER) C130 from GD-OTS Canada.
        As for your effectiveness questions, the 57mm gun is known to have good round to round dispersion. Round placement is more of a fire control / sensor issue. The Mk 48 Gun Weapon System on the WMSL, which includes the 57mm gun, uses the Mk 160 Gun Computer System and a combination of an optical sight & track while scan radar. It is my understanding that the version of the Mk 160 (Mod 12) for the USCG was designed to meet warning, disabling & destructive fire IAW Maritime Law Enforcement Manual, COMDINST M16247.1D use of force policy.

  10. Personally I’m comfortable with the 57 mm as far as it’s capability against vessels up to about 1,000 tons (WLB/210 size). Above that I start to have reservations about its ability to sink or at least stop a vessel manned by a truly determined crew. It might take hours to sink a large merchant ship. As for firing into the bridge, control might have been transferred to after steering. Using GPS and some video feeds it would be possible to pilot into a major harbor even after the bridge is blown away.

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