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Scope keeps loosening on the mount!

Recently ran into a Patriot in 308 and have around 300 rounds through it. I get it sighted in, and the scope keeps loosening and I have to re-sight. Bought it on sale at Academy Sports $295, factory scope, factory setup (not vortex!)

Back to Mossberg? Academy? Locktite?

This is a range play toy.
 
What exactly is loosening? Did you make sure the bases were torqued down correctly. Mine were nowhere near tight from the factory
 
I had trouble with one that I had to try and re zero a couple times. In my case, the scope was bad but it was used and given to me. In your case, that would be last suspicion. Do you know exactly what's loose?

Without knowing I would break it down and remove everything and put it back together in this order:
First clean all parts including the tapped screw holes for the bases
Lightly oil the underside of the bases and receiver where the bases mount being careful not to get oil in the screw holes
A drop of blue loctite in each screw hole
Set the bases and slowly tighten by going back and forth between/among screws
Set the rings and align as best you're able, I used a wooden dowel the same size as the scope tube
Set the scope and again tighten the rings by going back and forth with the screws

If at all possible, use a torque wrench with inch pound adjustment. Some guys never use a torque wrench and never have a problem. I don't trust myself to get close to spec without one. I purchased a preset Warne torque wrench and used it for rings and bases.

I've only successfully/properly mounted precisely one scope. Others may have a better way to trouble shoot this though.
 
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I like to put the loctite on the screw threads and let it dry a bit before installation.

This can make the screw hard to start sometimes so be careful.

But it won't get on the action. Some guns have thru holes, and the loctite can run down.
 
Thank you all for replying so quickly. It's the back screw olding the scope to the rail.

I'm new to bolt action rifle but I've mounted scopes to others.

After 3 or so rounds, the screw backs out and the scope wobbles. I've hand tightened the screw and the sequence starts all over.

My expectations are not that lofty, but die a new firearm, this behavior doesn't seem right?

I'm afraid of stripping the screw. Should I contact Mossberg or academy?
 
If the threads are OK, blue Loctite.

If the threads are worn, red Loctite.

If the screw threads are worn, new screw, blue Loctite.
 
Don't use loctite. You'll cause more problems in the long run. After you tighten the screws, give the screw heads all a dab of super glue, or clear fingernail polish. Keep the threads clean, secure from the screw head. That way you'll be able to take them back out later if you choose.

Sent from my SM-G360V using Tapatalk
 
It may make the OP 's life a little easier in the future should he decide he's not content with the setup. I've rounded out screw heads, and broken screws off that were secured with loctite when I went back later to change things.

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I used the blue loctite because it was recommended by both Leupold and in a Brownells video I think. The only place I use it was on the bases to receiver and not on the rings themselves.
 
Blue loctite has always been OK for me, but all loctite comes apart much easier if the metal is at least warm to the touch or hotter.

Here in the desert, just sit the gun in the sun 15 minutes, and it'll be too hot to touch, but blue loctite will soften up. Red likes it hotter, but it will eventually soften too with more heat.
 
I am late to this topic, for which I apologise.
Years ago, I was told that Loctite spoils the thread; that is, the metal. I never asked questions and Have taken it as Gospel ever since.
dieselmudder's fingernail polish #8, was popular in the "olden days":)
To remove Loctited screws, apply a soldering iron to the head:D
 
I have never heard that it spoils the metal, so I have to wonder in what way?

Maybe it is self-priming, meaning it etches the metal with acid.

I have also used cyanoacrylate glue (Krazy Glue) as loctite, and paint as well. Krazy Glue is tough when put on a clean assembly, but doesn't cure in air. What you put it on must be tight so to squish out all air. Then it sets in 2 seconds.
 
I go to a lot of trouble to make the gap each side of the ring as equal as possible. Feeler guages are a big help but it takes a Long time what with measuring each side and tightening, loosening:eek:
Something that sets in 2 seconds would not be appropriate in this scenario and FWIW, my rings are assembled dry.
 
I go to a lot of trouble to make the gap each side of the ring as equal as possible. Feeler guages are a big help but it takes a Long time what with measuring each side and tightening, loosening:eek:
Something that sets in 2 seconds would not be appropriate in this scenario and FWIW, my rings are assembled dry.

I don't use anything on the rings either though it's been recommended (not by manufacturers) to use blue loctite on them.

I strictly followed Leupolds guide with the aid of their videos, specific to each style of rings and bases, through their site.
 
I go to a lot of trouble to make the gap each side of the ring as equal as possible. Feeler guages are a big help but it takes a Long time what with measuring each side and tightening, loosening:eek:
Something that sets in 2 seconds would not be appropriate in this scenario and FWIW, my rings are assembled dry.

You can put it on after, and capillary action makes it suck up into the threads a bit.
 
I've bought Leupold rings, Tally rings, Redfield, Simmons, Weaver and Kwiksite too. Every one of my scopes has a different brand of rings.

One of them came from the factory with blue Loctite on the screws already, but I just can't recall which one.

But once I got a scope set up well, I loosened the screws, add blue Loctite. Then a final re-sighting.
 
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