This story starts out with a Mossberg MVP in 5.56 NATO.

I was offered a MVP rifle scope package in like new condition for a very reasonable price. Being a sucker for free market rifles I brought it.

I got it home put in the safe and kind of forgot about it.

A month or so went by I decide well at least I should see if it was really sighted in like the seller told me it was.

So I grabbed some 55gr ball and walked door the door to my rifle range.

I place a large piece of cardboard on the back stop about 3 feet by 4 feet. I placed a 2 inch target dot in the middle.

I went back to a hundred yards and fired a 5 shot group.

Well I thought it makes a heck of a shotgun. 18 or 20 inch pattern.

Back to the house to check the mounts and action screws. All were loose and the bedding really sucked.

So I set it aside deciding what to do with it. Well a week or so later I tighten every thing down. Went to the 50 yard line and fire a some what respectable 3/4 inch group.

Problem taken care of, OH No, shot it 100n by it is shooting patterns again.

Back to the house in disgust set it a side.

A week or so later and studying the problem. I decided the factory bedding block a mess. The action seems to be only making contact on top of the pillars.

So out comes the glass bedding and I bed the action in my usual manner front of the action first couple inches of the barrel. I make sure every thing is tight and shoot one decent 3/4 group at 100.

2nd group is about 8 inches well an improvement.


Take it back action screws are loose and scope mount screws are loose once again.


Well having it apart I decide. I well bed the back of the action also. So I did.

Put it back together take it and shoot it well at a hundred about a 2.5 inch group. Well and improvement from the 8 inch group.

Shoot it some more groups open up to about 5 inches. Get back to the house and find loose screws again. go into town and buy some blue loc tite.

A friend is coming up to do some MC riding I told him I would let him shoot it. He brought with him a
Busnell Elite Tactical 4.5-30x50 Mil-Dot scope.

We mounted that on the rifle. Not knowing where it was going to hit. We started at 50 yards. I loaded my standard PDdog load in the rifle.

52 gr Serria MKHPBT ahead of BLC2 this load has proven to be very accurate over the years with many sub half inch groups. Out of several varmint style rifles.

I fire 4 rounds 3 are with in 3/8th of an inch the 4th one that I pulled open it up to 3/4

10 inches low 8 to the left adjust shoot adjust shoot dead on at 50. Ok out to a hundred.

Hand it to my friend to who is a excellent rifle shot. Who has shot on the Hornaday team.

5 shots 6 inch inch group. Take to the house action screws and scope mount screws are loose again.

So that is where I am at.

Next step glass the mount and screws to the rifle. Clean and loc tite the actions screw again?

Getting very frustrating.

Tighten the screws and sell it. Get a new one that is not a pain.

I just couldn't trust a rifle with those issues. If your experiences were mine that rifle would be long gone. While theoretically all the problems are fixable I would be too worried about problems arising again unexpectedly. Better off starting again with something that can be relied upon in my view.

Check your threads on your action screws and scope mount screws. Sounds like they are stripped to me.
Best of luck.

I think he would notice stripped screws.

You might have oversized holes or u derailed screws or both.

I would try some Locktie that can be removed with wrench pressure and if you really want to keep it call Mossbwrg and get new screws and see if that helps.

Just think you have the perfect long range duck gun with those great patterns!!!

the screws might be the problem or it is the holes.
you might have to re-tap from a 6 to an 8 for the scope.

When I mount scope bases I tighten each screw one at a time to ensure each screw is actually pulling down on the base/s. When satisfied that screws are not bottoming out or stripped I then screw the base/s down with two tube/pot epoxy glue on the underside of the base/s and on the screw threads.
I will not mount any scope base/s for myself or others without using this method and epoxy glue. Things do not ever come loose when mounted this way.

As for scope rings I ensure the screw threads are lightly oiled, this helps set and hold them. Ring screws rarely ever give trouble provided they are not stripped through heavy handed tightening.

Epoxy glue will soften and can be removed from surfaces and threads if some judicious heat is applied but do not glue action screws as you cannot get heat to the thread area to 'unlock' them, use blue loctite instead. Check to see that the action screws are not bottoming out or semi-stripped too.

A heavy scope on a 223 rifle should not give any base or ring screw problems as recoil is negligible.

With groups like that, I would dump the gun on my worst friend, or rebarrel and start over..YOU BEEN AROUND LONG ENOUGH TO KNOW THAT!!

quote:

Originally posted by buckeyeshooter:
Tighten the screws and sell it. Get a new one that is not a pain.

My son and I made a similar mistake. Sold it and bought two Daniels great guns.

My father had the same issue (sort of) with a custom built 35 Whelen that he had made from the ground up. After multiple attempts of "changing this and messing with that" he finally gave up. He tried multiple loads, factory loads, taking it apart and putting it back together and he couldn't get it to shoot inside of about six inches at 100 yards. He never knew what the problem was. As good as Robert is at building guns, I know it was nothing that the gunsmith did. seems like EVERY NOW AND THEN, it is just bad luck of the draw...

quote:

Originally posted by Atkinson:
With groups like that, I would dump the gun on my worst friend, or rebarrel and start over..YOU BEEN AROUND LONG ENOUGH TO KNOW THAT!!

Is the scope any good? Maybe start with iron sights?

quote:

Originally posted by Lamar:
the screws might be the problem or it is the holes.
you might have to re-tap from a 6 to an 8 for the scope.

This ^^. They were probably over tightened and wrecked the threads.

quote:

Originally posted by TomP:

quote:

Originally posted by Atkinson:
With groups like that, I would dump the gun on my worst friend, or rebarrel and start over..YOU BEEN AROUND LONG ENOUGH TO KNOW THAT!!

Is the scope any good? Maybe start with iron sights?

Read the posts by p dog shooter. He says that after every shooting session when initial groups are acceptable and then groups start to open up, the action screws and scope mount screws are loose again. This is nothing to do with the scope which is fine if it shoots acceptable groups until the screws work loose.
The 223/5.56 has minimal recoil so we are not talking about a heavy kicker which could give problems if things were not perfectly matched and tight.

Action screws and scope mounting screws that come loose after a few shots with a 223/5.56 have been stripped or the action threads and scope mount threads on the action are likewise, or the screws are bottoming out. Possibly a replacement stock or bottom metal has been fitted at some stage which is causing the action screws to bottom out. With action screws you should feel the difference between pulling the action snug down into the stock or the screws just going hard as they bottom out.
With scope mount screws, screw each down one at a time until tight and then see if the scope base/s can be wriggled, indicating a bottomed out screw.

As per my first post I do not apply loctite or epoxy glue to any base or thread until I am certain the screws are doing their job properly, only then do I glue everything up, never to move again. There will be a simple explanation.

What I read is that is not a problem with the rifle, but with the fire direction assembly. Meaning the scope, rings, mounts, screws, or some combination.
I recommend getting a new set of those components, and have someone who knows how, install them.
I have seen this before, and it is rarely the rifle. It would be hard to make a rifle shoot 3 foot groups.
And, double spacing is really hard to read.....

For now I set it in my burglar bait rack.

I rack of poor firearms set out in the open.

Serial no. and other Id marks well recorded.

Hoping that if I do get hit they well grab that stuff and run.

You should have sent it back to Mossberg for correction. Now they won't touch it. We had a brand new Savage Axis in 6.5 Creedmore in the shop that wouldn't hit a 2'x 3' target at 25 yds. The target next to it got hit with two keyholes. Sent it to Savage and got a different brand new rifle back that groups into little cloverleafs.

quote:

Originally posted by dpcd:
What I read is that is not a problem with the rifle, but with the fire direction assembly. Meaning the scope, rings, mounts, screws, or some combination.
I recommend getting a new set of those components, and have someone who knows how, install them.
I have seen this before, and it is rarely the rifle. It would be hard to make a rifle shoot 3 foot groups.
And, double spacing is really hard to read.....

Are action screws not part of the rifle???? Read the OP's initial post, they are mentioned coming loose three times along with the scope mount screws.

My apologies if I have got it wrong, but I have assumed "action screws" are those holding the barreled action in the stock and "scope mount screws" are those holding the bases to the action. These are the commonly used terms.

quote:

Originally posted by eagle27:

quote:

Originally posted by TomP:

quote:

Originally posted by Atkinson:
With groups like that, I would dump the gun on my worst friend, or rebarrel and start over..YOU BEEN AROUND LONG ENOUGH TO KNOW THAT!!

Is the scope any good? Maybe start with iron sights?

Read the posts by p dog shooter. He says that after every shooting session when initial groups are acceptable and then groups start to open up, the action screws and scope mount screws are loose again. This is nothing to do with the scope which is fine if it shoots acceptable groups until the screws work loose.
The 223/5.56 has minimal recoil so we are not talking about a heavy kicker which could give problems if things were not perfectly matched and tight.

Action screws and scope mounting screws that come loose after a few shots with a 223/5.56 have been stripped or the action threads and scope mount threads on the action are likewise, or the screws are bottoming out. Possibly a replacement stock or bottom metal has been fitted at some stage which is causing the action screws to bottom out. With action screws you should feel the difference between pulling the action snug down into the stock or the screws just going hard as they bottom out.
With scope mount screws, screw each down one at a time until tight and then see if the scope base/s can be wriggled, indicating a bottomed out screw.

As per my first post I do not apply loctite or epoxy glue to any base or thread until I am certain the screws are doing their job properly, only then do I glue everything up, never to move again. There will be a simple explanation.

I may have blinders on here, I've had more trouble with scopes than screws (knock on wood).

quote:

Originally posted by TomP:

I may have blinders on here, I've had more trouble with scopes than screws (knock on wood).[/QUOTE]

I would agree with that statement but in this case we seem to be talking about the action screws coming loose too and the OP talks about the bedding being crap so I've assumed, rightly or wrongly, that the action screws the OP says are coming loose are those holding the barreled action in the stock, nothing to do with scope bases, rings or the scope.

Maybe the OP will clarify just what screws he is having trouble with.

I just actually read the OP post, something I rarely do before answering. It does save time.
I think I now read that BOTH the scope screws, and the Action screws, are coming loose after 5 shots. ON A 223!!!
The two items are not related at all.
Now, I have been shooting rifles of every make and model, for over 6 decades now, and have NEVER had either one come loose. Ever. Action screws and scope screws coming loose at the same time, every time, after a few shots?
Think about that for a minute.
Something is very wrong here. Very wrong. Not sure with what.
Let's take a survey; how many AR members have had this happen?
I predict, ZERO.
Bad luck? Of course, I am not saying it didn't happen. Not at all.

I'll bite. Zero here, 60+ years, never ever.

Scope screws - yes, a couple of times. One my fault. The other due to oversize ring.
Action screws - never.

If it were mine, I would remove action from the stock (again) and check how the action screws fit in their holes. Just screw them in two turns and see how much they wobble.

If the scope rail was coming loose, I would do the same with those screws. I might do the same with the scope ring screws that are coming loose but it might be easier to just replace the rings entirely.

I have advised how I would be checking screws in my earlier post. The OP purchased the rifle and scope package in near new condition but did not get around to firing it for a month or so later. The first shots at 100 yards produced a pattern like a shotgun so the OP says. That is when he found both the action screws and scope mount screws loose, so they were all loose when he purchased the rig, or the previous owner had tightened them up after they came loose on him and passed on the rifle. The OP has had to retighten the screws after firing the rifle on three different occasions.

I would love to have the rifle, bet I could identify the problem and sort out a fix for it in a few minutes.

As I've suggested in sofar as the action screws go, I'm thinking the stock and or bottom metal has been replaced at some stage changing dimensions whereby the action screws are bottoming out and not pulling the barreled action down tight into the stock. Likewise with the scope bases, bottomed out screws, loctite won't fix either of those two problems.
It's possible all the screws have been semi stripped although I'm sure the OP would have had to notice that when he tighten everything up on each of the three occasions, wouldn't he?????

quote:

Originally posted by Bobster:
You should have sent it back to Mossberg for correction. Now they won't touch it. We had a brand new Savage Axis in 6.5 Creedmore in the shop that wouldn't hit a 2'x 3' target at 25 yds. The target next to it got hit with two keyholes. Sent it to Savage and got a different brand new rifle back that groups into little cloverleafs.

It was used when I brought it

quote:

Something is very wrong here. Very wrong. Not sure with what.
Let's take a survey; how many AR members have had this happen?
I predict, ZERO.
Bad luck? Of course,

As with many items made by mass production some times things just don't fall together.

Out of the many dozen of rifles I have own. Out of the many dozens I have helped friends with. Out of many dozens I have mounted scopes on glass bedded etc.

This one is a puzzle.

quote:

Originally posted by p dog shooter:

quote:

Something is very wrong here. Very wrong. Not sure with what.
Let's take a survey; how many AR members have had this happen?
I predict, ZERO.
Bad luck? Of course,

As with many items made by mass production some times things just don't fall together.

Out of the many dozen of rifles I have own. Out of the many dozens I have helped friends with. Out of many dozens I have mounted scopes on glass bedded etc.

This one is a puzzle.

p dog shooter it seems your rifle shoots acceptable groups when you start out with all screws nice and tight so there doesn't seem to be anything inherently wrong with your rifle in terms of barrel accuracy.
Of course no rifle will group with loose action and or scope base screws.

The problem you need to solve is why are the screws coming loose. It is just not logical that these screws keep coming loose if they are not bottomed out or stripped especially so on a low recoiling cartridge like the 5.56/223.

Until you resolve the loose screw saga it is no use blaming a poor rifle, poor barrel or anything else. I repeat no rifle, just no rifle, will group with loose action or scope mounting system screws, fix that and you'll have a good rifle.

quote:

It is just not logical that these screws keep coming loose

You are completely right not logical at all. If it was logical I would have solved the problem as I have done on many rifles.

I do not need the rifle I do not have much money into it.

I have set it aside for now.

Well you could glass bed it or rebed it, have a smith check it over for scope malfunctions starting with a change of scopes, do the usual investigation by reducing the probables or just rebarrel the gun. depends on how much your willing to invest on a Mossberg!

I will say this, if the groups are that large its more than unusual and its a oversize bore/

quote:

Originally posted by Atkinson:
Well you could glass bed it or rebed it, have a smith check it over for scope malfunctions starting with a change of scopes, do the usual investigation by reducing the probables or just rebarrel the gun. depends on how much your willing to invest on a Mossberg!

I will say this, if the groups are that large its more than unusual and its a oversize bore/

Well if you read the whole thread you would find out most of that has been done.