Loctite - Where, which kind, how often?

[Moltke]

So there's going to be differing opinions on this from "you don't need any" to the other end of the spectrum with "use it on everything", but I'd like to know from high round count shooters here on M4C - where do you put loctite on your AR's? Which kind do you put in these places, and how often do you check it, add more, etc.

[munch520]

A little 242 on any screws used to mount accessories to the rail. Used to locktite the castle nut til I stripped an A5's threads trying to get it off. Staking only for me after that.

[Eric]

Blue Loctite 242 is removable with hand tools and goes on: optic mounts, sling mounts, BUIS, light mounts, rail mounted grips, etc. It does not go on: receiver extension, receiver extension nut, barrel nut.

[SHIVAN]

I use the red loctite on the grip screw, optics/light mount screws, BUIS screws, and a very small additional drop on rail screws, like on the DD Lite. I use one drop on the screw thread, and assemble as normal.

I also use Rockset on my flash hiders and suppressor mounts.

I do not use loctite on castle nuts, barrel nuts, any small upper/lower parts.

[MarkG]

Vibra-Tite VC-3 (http://www.vibra-tite.com/vc3.php) is a reusable thread locker that I use in several locations including the receiver extension nut, grip screws and optic mounts. Like Loctite, it comes a couple of colors but the orange variant is all that is commercially available in small quantities. It is very viscous and can be applied exactly where you want. It doesn't require extensive degreasing prior to application. It sets and is ready to use a couple of minutes after application.

[556Cliff]

Everyone always says to use the blue 242 or the red 271, these most common threadlockers work fine with active metals if you use a primer before you apply them, but with this rifle we are dealing with mostly inactive metals.

So I recommend to use Blue 243 and red 263 primerless threadlockers.

[munch520]

Vibra-Tite VC-3 (http://www.vibra-tite.com/vc3.php) is a reusable thread locker that I use in several locations including the receiver extension nut, grip screws and optic mounts. Like Loctite, it comes a couple of colors but the orange variant is all that is commercially available in small quantities. It is very viscous and can be applied exactly where you want. It doesn't require extensive degreasing prior to application. It sets and is ready to use a couple of minutes after application.

Great point. I had never heard of the stuff til it came in a Gear Sector package recently.

[JW1069]

I also use the http://www.vibra-tite.com/vc3.php. The screw's clamping force comes from the last couple of threads so you only need a small drop of the VC-3 to get the hold that you need. You can also remove and reinstall the screw a few times without the need to reapply it each time. Basically anything mounted to my rifles with a screw gets a drop of the VC-3, although I prefer to leave the end plate staked and do not use any thread locker there.

[ST911]

Blue (242?) on everything with threads, with the exception of the flash hider, barrel nut, and receiver extension installation. Witness marks on most things. Screws are checked periodically.

[Scoby]

Blue (242?) on everything with threads, with the exception of the flash hider, barrel nut, and receiver extension installation. Witness marks on most things. Screws are checked periodically.


This but I'll add:

Flash hider gets Rocksett
Barrel nut gets anti-seeze
Receiver extension gets castle nut staked.

[Col_Crocs]

Vibra-Tite VC-3 (http://www.vibra-tite.com/vc3.php) is a reusable thread locker that I use in several locations including the receiver extension nut, grip screws and optic mounts. Like Loctite, it comes a couple of colors but the orange variant is all that is commercially available in small quantities. It is very viscous and can be applied exactly where you want. It doesn't require extensive degreasing prior to application. It sets and is ready to use a couple of minutes after application.

THANK YOU!!!!:thank_you2: I have been digging allover M4C to find that old thread that mentioned this thread locker. :jester:

[Rattlehead]

Loctite on any rail screws, Rocksett on my FH/brakes.

[An Undocumented Worker]

It aint Franks Red Hot, so no don't put that shit on everything. That said, I usually put a drop of blue on the mount screws for back up sights, rails and rail mounted accessories.

[bsmith_shoot]

I got a question to add to the ones the OP already asked, if you apply 242, and then a few days later you loosen that screw, do you need to put it on again?
Brandon

[Kokopelli]

I got a question to add to the ones the OP already asked, if you apply 242, and then a few days later you loosen that screw, do you need to put it on again?
Brandon

You need to clean the threads of all residue and reapply.. Ron

[badness]

I use the red loctite on the grip screw, optics/light mount screws, BUIS screws, and a very small additional drop on rail screws, like on the DD Lite. I use one drop on the screw thread, and assemble as normal.

I also use Rockset on my flash hiders and suppressor mounts.

I do not use loctite on castle nuts, barrel nuts, any small upper/lower parts.

you use RED loctite on those things? Wow. Once you've made up your mind, there's no turning back eh? :fie:

[ICANHITHIMMAN]

Why are you guys putting anything on your barrel threads?

[SHIVAN]

you use RED loctite on those things? Wow. Once you've made up your mind, there's no turning back eh? :fie:

I've found it's not as "permanent" as they say it is. Nor have I ever need heat to remove items. I also use a tiny little teeny drop. I am not dousing these things in loctite.

[Bob Reed]

Hello,

Since most gun screw are less than 1/4" inch in Diameter, let's take a look at what LOCTITE® has to offer for 1/4" Dia and under.

First, theres Blue No. 220, but, it's a wicking grade thread locker for pre-assembled fasteners up to 1/4" Dia., so, it's pretty much out for gun use.

Second, theres Purple No. 222 for fasteners up to 1/4" Dia., but, it doesn't meet certain agency approvals such as MIL-S, ASTM D, Ect..

Third, (and thankfully) theres Purple No. 222MS, it's an easy removal thread locker designed for fasteners up to 1/4" Dia., and, 222MS meets the approvals of many different agencies including MIL-S.

So, going by the LOCTITE® Catalog, it sure looks like Purple No. 222MS was specifically designed for fasteners up to 1/4" Dia. and is the best suited thread locker that they offer for small gun screws.

What makes the Purple No. 222MS so much better for small gun screws? Well, it's viscosity was designed for small screws & threads (it stays in the threads during assembly), it's easily removalable (so it's helps save your screw driver tips, screw heads & threads), not to mention it was specifically designed for small screws that's under 1/4" in Diameter.

Clean & Dry your parts well, and always Use a primer when "both" surfaces are considered inactive, ie. Plated Parts, Anodized Aluminum, Titanium, Stainless Steel, Galvanized Steel, Zinc, Pure Aluminum, Cadmium, Magnesium, Natural or Chemical Black Oxide, Magnetite Steel, Iconel, Silver, Gold & Plastics.

Active Metals are considered to be, Iron, Plain Steel, Copper, Brass, Commerical Aluminum, ie. T 6061, Bronze, Nickel, Maganese, Monel & Kovar.

LOCTITE® 7471 Primer T has a 7 day on-part-life, and LOCTITE® 7649 Primer N has a 30 day on-part-life and is Ideal for cure conditions below room temperature. So, if it's room temp or above and your gonna install your screws in 7 days or less, use 7471 Primer T, and if your in colder areas use 7649 Primer N.