Listen to me, my children, as I pass down the wisdom of all the Tactical Handymen before me. When it comes to guns and gear – if it has threads, it gets Loctite (or a similar thread locking compound). The only exception is when the manufacturer says otherwise. Recoil can and will loosen threaded fasteners over time. Thread locking compound can prevent that from happening.
Most manufacturers color code their thread locking compound. The blue stuff is all you need for most applications, but if the part will be subjected to high heat, go with the red stuff or some other product intended for use with high heat.
Use thread locking compound on:
- Optic mount screws
- Flashlight mount screws
- The set screws on your handgun sights
- Sight adjustment set screws
- Grip screws on your carbine
- The screws that hold your holsters to their belt interface or shroud
- Almost anything with threads that would ruin your day if it loosened
- Seriously, use it – a lot
Don’t use thread locking compound on:
- AR-15 receiver extensions/buffer tubes (these should be staked at the castle nut)
- The nut on a Larue Tactical QD lever
- Anything you need to be able to unscrew later
- Anything that the manufacturer specifically states not to use thread locking compound
No one wants to deal with threaded fasteners that back out. At best, you will have to re-zero an optic costing your time and money. At worst, something could fail you at a critical time. Please go get some thread locking compound and add it to your toolbox.