Salt Water AR-15

[Sebastian the Ibis]

I am helping a friend but together an AR-15 for his boat. This AR will be shot little, but it will spend most of its time in humid sea air and will be cleaned/maintained infrequently if at all. Does anyone have suggestions for AR-15 components suitable for a marine environment?

Any reason not to go with a mid-length PSA freedom kit?

http://palmettostatearmory.com/psa-16-midlength-5-56-nato-1-7-phosphate-moe-freedom-rifle-kit.html

 

[GooseGestapo]

Standard AR15. Chrome lined bore, 16"carbine.
Uncle Sam knew something about adverse environment and has had 50yrs to get it right.
Standard upper, open sights. Collapsible butt stock, get compact hard case.
I never kept firearms in my patrol boats when not in use. Too harsh and too easily stolen.

You want them to work if you need it! That means regular attention and proper storage.

Added: the one with the stainless barrel would be better. # 7778692. I went with a polymer lower on my last build. I Really like it! Not crazy about the mid length gas system with a .300BLK. Undergassing issues.

 

[briansmithwins]

Salt water and aluminum are not good friends, especially when combined with infrequent care.

I'd also avoid stainless steel as it's galvanic potential is more than carbon steel. The aluminum with suffer increased corrosion but will protect the stainless component from damage, the aluminum becomes the sacrificial anode.

If it were me, I'd start with a decent build or an AR, and get the NP3 coating from Robar: https://robarguns.com/custom-firearm-finishes/np3/

Or get the entire thing painted with one of the good epoxy paints: Duracoat, Cerakote, etc.

I agree that the best starting point would be a carbon steel barreled, hard chrome bore and chamber AR.

BSW

 

[silicosys4]

As someone who has seen a lot of firearms used on boats,
It doesn't matter so much the type of firearm, as much as how you maintain it.
I have seen stainless guns rusted pretty badly, and I've seen spotless carbon steel
The only thing that would stop any gun from rusting,
was constant care.
The guys who left their gun in the boat every night had rusty guns
The guys who took their gun off the boat every time they got back to the dock, took it home, and oiled it back up and kept it well protected at sea, had guns that were rust free

 

[Reloadron]

This AR will be shot little, but it will spend most of its time in humid sea air and will be cleaned/maintained infrequently if at all.

Then you will have an AR that lives a short life and will likely be undependable in short order. You can look into anodizing the aluminum but even with that good luck along with a thin coat of oil. While I was never in the US Navy I did work as a civilian component of the DoD including deployments on US Naval Ships. Corrosion control is a forever running battle. Salt water and air can be nasty on even well maintained firearms.

Ron

 

[W.E.G.]

cleaned/maintained infrequently if at all

This is unacceptable.

Owner must do better.

 

[Slamfire]

Silicosys4 has it right, a salt air environment is one of the most corrosive environments, perhaps the most corrosive natural environments ever. Whatever your friend buys, with sufficient neglect, it will turn into a pile of corroded metal. Be it aluminum, stainless, or something else.

 

[z7]

As others have mentioned, salt water is very harsh, it destroys almost everything including stainless steel. It is critical that the weapon be heavily oiled and the salt frequently rinsed off the rifle. Unless your friend just wants to throw money away and not have his requirement met, he must frequently maintain the weapon

 

[X-Rap]

Pelican case and reasonable maintenance and he should be fine.

 

[briansmithwins]

Seal it in a VCI bag away from the boat?

Or just replace it yearly as it corrodes out.

BSW

 

[119er]

Seal it in a VCI bag away from the boat?

That about answers it. Get whatever he wants in the rifle, the options are endless. Take it to the range, zero and test fire, clean/ lube as normal and seal it in a VCI bag as suggested above. Check condition at the normal maintenance intervals for the boat itself. Done deal.

 

[MachIVshooter]

Agree with others. Unless the thing is vacuum sealed or basically swimming in lubricant, that environment will attack any gun badly.

 

[silicosys4]

Gun cases with foam linings are bad mojo on saltwater, they soak up salt spray and humidity and then start eating away at whatever is inside.
Best results I've seen is a pvc dry bag and lots of RIG, in addition to religious maintenance.

Might be a good use for a polymer AR build, a saltwater boat gun.

 

[HKGuns]

Send it in to Robar and have everything NP3+ coated.

 

[carbine85]

Stainless is used a lot on boats. I don't see why it shouldn't be used for this application. I would use some type of thread sealer or compound on the barrel nut and receiver. You might look into a good baked on paint for all the parts.
A NiB or Nitrided bolt carrier group might help here.
You might consider this, I've been using Mobile SHC 100 red grease the last 3 years for bolt guns and AKs. I rub it into surfaces as a lubricant and protective coating. The stuff is really slick, smooth and stays put. I have 1 AR frankengun that is lubricated with this, no oil. Everything is rubbed down with it. It's one of the smoothest running ARs I have.

 

[lemaymiami]

I second the use of Rig as a protectant (old school light grease that really seals up surface metal) but have to say that I carefully keep weapons off my skiff unless I'm certain they're needed since I work out of that skiff and have a pretty fair knowledge of how badly things fare in that environment. I keep a weapon in my tow vehicle (and I'm towing that little skiff 20k per year -year in and year out).

Seriously, if the weapon is much more of an "in case" proposition my advice would be only to have it on that boat when you have reason to believe it's needed. I know that will be counter intuitive but as a guy who spends 100 to 200 days a year on the salt I'd expect serious problems with any weapon stored on a boat unless it was removed every time you left the boat and religiously maintained every week....

 

[Longhorn 76]

Get it coated with BlackT, like the U.S. Navy and coast guard use for their deck guns. Or so I was told.

 

[briansmithwins]

Stainless is used a lot on boats. I don't see why it shouldn't be used for this application.

Stainless in direct contact with aluminum would likely lead to galvanic corrosion, unless he bolts zincs to the receiver.

BSW

 

[eldon519]

Is he actually gonna get the gun out and use it or just stow it and forget it? If it's a stow it and forget it situation, just seal it airtight with some kind of grease or wax on the surfaces and maybe some desecant packets in there, and I suspect it would be fine.

As mentioned, one of the challenges with an AR15 is lots of contact between dissimilar metals such as all the lower receiver parts and pins, dust cover and forward assist, barrel to receiver, etc. It might not be as durable, but there are polymer upper and lower receivers out there which might help.

If you plan to get it out a lot and still want to neglect it, I might use and AK since it's all steel and get the whole thing coated. I don't know if you could melonite the whole thing or something like that, but that might work. Put on synthetic stocks and coat it in grease.

 

[MachIVshooter]

Stainless is used a lot on boats. I don't see why it shouldn't be used for this application.

Some grades of stainless are highly corrosion resistant, some not much more than carbon steel. 304, for example, is a very common stainless used in a lot of cook ware, liquid tanks, etc, and would probably hold up fairly well to salt water. But stainless barrels are almost always made of 416, which is a ferritic type (will be magnetic). It is more machinable and can be heat treated to a hardness required for barrels, but it will rust.

 

[ApacheCoTodd]

I'd shift priorities:

Worry less about what it is made of or coated with and more about successfully removing it from contact with sea air.

Goo it up a bit and seal it with one of those inexpensive vacuseal bags.

If he doesn't think he's going to get into quick draw gun battles with some cartel navy or hordes of Somali pirates there's a cheap-quick option we used in the Army:

He can use simple contractor grade trash bags, sink a properly lubed AR into a tub, basin, pool... whatever (inside the bag), with the opening of the bag of course outside of the water. Muzzle up, roll the opening closed to the muzzle and tape or zip tie.

You can play around with options for quick opening and deployment should it come to that.

Remember one important thing though if expecting to rapidly deploy a bagged AR: You must remember to clear the ejection port too.


Todd.

 

[Zerodefect]

Use a melonite barrel and bolt carrier group.

Relube and coat frequently. The operator is a moron if he thinks he can just hang it on the wall of his boat an ignore it. The gun bag isn't a bad idea.