Loctite - Good or bad

I've never been one to use Loctite on scope screws for the simple reason that nothing is permanent. Something happens and you find yourself needing to remove or replace your scope. I was reminded of it this past weekend when a friend encountered a loose scope base on his rifle. Whoever owned the scope before him must have used Loctite on the ring screws because they wouldn't break loose. Fortunately, the base was the Leupold type with a dovetail base on the front ring and double screw base (which some despise) on the rear. This made it possible to remove the scope with the rings still attached.

I understand there are remedies for screws that have been seized with Loctite, and that other blends of Loctite are available that don't create a more permanent setup. Not sure the potential hassle after using Loctite warrants the benefits.

Use blue Loctite and it’s not an issue.

Does this offer an benefit over not using any thread locker?

blue loctite good, red bad for most things

yes, blue is removable with extra force, red needs heat to remove

Loctite purple is a better alternative to blue---if you can find it. But blue is definitely a better choice than red. Don't use red.

Beware of green also, it is a wicking formula that will seep into threads already tightened which is nice but it is almost as strong as red and usually requires heat to loosen. It is also hard to find.

Loctite 222 purple is designed for fasteners 1/4" and under, what I use on base & ring screws.
Blue is for 1/4" - 3/4" fasteners, you can use it on base & rings, but, if you have to remove & replace a fastener as small as most base & ring screws the cured residue remaining in the threads will make it near impossible to torque accurately unless residue is removed.

Yeah I know, it's another one of those my grandfather & father and 116 people I know have always used blue and never had a problem kinda deals.
Purple is plenty strong for the application & specifically developed & designed for small / tiny fasteners 1/4" or less.

Here's another question for those most familiar with Loctite.

Should a screw be tightened as hard when using Loctite as it would if not using it?

Ive never used it on anything. Haven’t had a problem. The only place I would consider using it would be for base screws.

Loctite reccomends reducing toque by 20%, which is I'm sure a standard / general answer.
When I tested the friction factor & calculated a K value for purple with my specific base screws for my rem LTR I came up with an actual 12.525% less.

It might be the PO was just a gorilla with a good gunsmithing screwdriver and didn't use locktite.

Loctite is good when used properly but can get really bad real fast when used improperly.

I never use it anymore. With todays quality mounting systems, I don't believe its necessary. But this just me. Torque tool is your friend.

I use purple when mounting bases to the action. I will use them on rings that only have one screw on each side.

purple is also better for aluminum, such as AR receivers. About the only place I use it is large caliber scope mounts, big heavy scopes (like night vision) and when building AR receivers I always do an upgrade adding a set screw to take out the trigger creep...do not want this screw to move or it will cause problems!

good info here

True! I keep a bottle of "red" in the garage for use on some engines, it somehow ended up on my gun bench in the house. Since Loctite bottles are all colored red I thought it was the blue that I normally use there and used it on a trigger set screw When I took it to the farm to test the screw was in too far and needed to be adjusted..NOT HAPPENING! After getting back home with it I had to tear it down and use a small pencil torch to heat and remove it....

That's what I was thinking.

I learn something new every day.

Skylar says no just torque to proper inch lbs.

Unnecessary and it voids some manufacturers warranty. Torque to the manufacturers specs and you'll be fine. Trust in their instructions. Torque specs vary by manufacturer due to tolerences and materials but they know how snug their rings need to be. I've never quite understood the whole loctite thing. There's probably thousands of screws used in various pieces of equipment and moving parts that we all own. Few to none need loctite, I don't see why scope rings should.

I use blue loctite or nail polish on a lot of things, scope rings and bases included.

I like the insurance of using Loctite Blue. Maybe I need it and maybe I don't but I use it.

Warranty policies may be what they are, but look around at how many guys find that their mounting hardware has loosened after noticing a POI change. If you choose to believe that if it hasn't happened to you it therefore just doesn't happen, you may lead a charmed life all the way to the end...or NOT.

How would you feel about flying in an airplane that doesn't have a single drop of loctite on a single fastener, anywhere? I know how I feel about it. And now that I think about it...I can't count the number of times I've found hardware on the floor around the house and in the garage. That stuff comes from somewhere...and I'm left to wonder what's going to break down next. And believe it or not, many manufacturers of various products implore the use of thread lockers on fasteners.

Same here.

Use blue picture on a few things mostly just bases

How many knew this about thread lockers...


"Because electrochemical activity is one of the two triggers that cause polymerization of the threadlocker fluid, care must be taken to avoid contaminating the entire container of threadlocker with threadlocker that has had contact with metal, otherwise the material in the container may polymerize."

Been using Guntite for a lot of years with no issues:

https://www.midwayusa.com/product/1006527431/uncle-mikes-gun-tite-removable-threadlocker-6ml-tube

It's definitely some weird stuff. There's a good Wikipedia article on the development of loctite...interesting.

Good discussion of a topic where there is no perfect answer, with the exception being Loctite Red or other premanent thread locking fluid. It's not a good solution unless you believe you will NEVER need to remove a screw. And never is a very long time.

Loctite used to never give a K value for their product nor a recommendation for torque. All they would say is to test on your own and calculate a K value right before your application. I would guess it was because of legal reasons and because their product changes viscosity under different temperatures.

I use blue and drop torque down 10-15% at room temp and haven't had any issues so far. No problems removing screws either... so far.

Good info. I use blue Loctite but I never thought about changing torque when using it. When you wade through the BS there are some pretty smart dudes hanging out here.

Low strength Loctite, and still torque to spec, on base to action, and ring cap screws. That's what I do.

The OP's question was addressed in depth here.......

https://www.24hourcampfire.com/ubbthreads/ubbthreads.php/topics/12394775/1

FWIW - I worked in the defense industry for 17 years with many brilliant engineers where it was established all fasteners required a locking mechanism with a Loctite type thread locker being much preferred over locking washers. Some of my airborne systems had in excess of 1,500 fasteners. I ran both a repair depot and production factory and will attest to thread locker being critical, especially for small screws. It is for this reason I always use Loctite blue or purple on all firearms. Proper torque is not enough for these small screws based upon my experience along with a lot of engineering analysis I've seen.

I've not had any difficulties removing scope rings or bases using blue or purple.