Mossberg 590A1 ghost ring issues

[PitBull]

Got a question for you experienced Mossberg 590 ghost ring users.

I have a 590A1 that I bought used a few weeks ago. Today I shot some slugs though it off of the bench just to get the sights adjusted for them.
Even at 25 yards I had to have the elevation adjusted almost all the way to the highest setting to get it in the 10 ring at that distance. The slugs were Brenneke KO.
I have rifles with aperture sights so I know what the sight picture is supposed to be. I had the top of the front sight right on the 10 ring. I could get some other slugs and try them but I can't see them making that much of a difference.

Is this problem familiar to anyone?

[Sarge]

I bought a half-dozen 590-A1's for a little Sheriff's Dept., 20 years ago, and spent an afternoon zeroing them at 50 yards with 2 3/4" Super X slugs. As I recall, nearly all of them required at least half of the elevation adjustment to get them 'on'. All of them did zero, however.

Sounds like Mossberg is still using plenty of front sight... I'd take a file to it, if it bothered me, and touch up with cold blue and model paint.

[PitBull]

Thanks for the reply.
If it used half the elevation to get to 50 yds I wouldnt mind but it's using nearly twice that to get half the distance.
At this point if I were to go with front sight filing I'd be down to a nub by the time I got it down enough.

[zippy13]

>I have rifles with aperture sights so I know what the sight picture is supposed to be.

Perhaps you and Mossberg differ in this. I was taught to use a six-o'clock (punkin on a fence post) sight picture with aperture sights and bullseye-type targets. Other's advocate a centered sight picture. Obviously, mixing methods can result in vertical differences equal to the radius of the black. Frequently we see similar questions on sight alignment, and many opinions are offered without questioning the OP's sight picture. The Mossberg owner's manual addresses adjusting the ghost ring sight; but, makes no mention of the "proper" sight picture nor what slug weight/velocity is recommended.

[PitBull]

A 6 oclock hold would put my POI even lower.

[Icopy1]

Call Mossberg and ask them. There could be a problem with your weapon. Or it could be designed to use a particular load.

[hogdogs]

Maybe a different cheek weld position?

Brent

[PitBull]

I beleive i will call them. I just wanted to see if this is a common issue with this model first.

[PitBull]

Mossberg said to send it back to them and that it's still under warranty so I did. It arrived there today. When I comes back (no telling how long) I'll shoot it and come back here with the results.

[Hoosier_Daddy]

Bummer that you received a defective one. Hopefully they will turn it around quickly and make sure you are satisfied.

[Delaware_Dan]

Mossbergs front sights are not the most QCed on the market. The 930 SPX had a run of shotguns with a canted (to the left if I remember) front sight. Since I read this online I went to Dicks and my LGS, and yup, canted to the left buy quite a bit. I hope Mossberg makes this right.

[Malpaso]

I walked into a 3 gun shoot today without zeroing mine and was off about 6" to the left at 50 yards. I can't seem to find the "adjustment per click" information anywhere. I'd like to get a general idea of windage adjustment before sighting it in. Anyone have that information?

[zippy13]

I can't seem to find the "adjustment per click" information anywhere. I'd like to get a general idea of windage adjustment before sighting it in. Anyone have that information?

Perhaps there's a Mossberg ghost-ring owner out there with a laser bore sight. It could be used to estimate the sight's clicks-per-inch at a given distance.

[PitBull]

After a 1 1/2 months it finally came back. I don't know what they did to it but they sent a copy of a bullseye target marked "50 yards" with a 3 shot slug group in the 10 ring that measures about 2 inches center to center.
If it really does that well for me I'll be ecstatic!
I won't have time to go shooting this weekend but I will in the next few weeks. There was nothing stating what had been done to correct the issue. The only thing changed visibly is that there was a small scratch on the barrel that's no longer there. That means they either touched up the scratch just because or it was a bad barrel and they replaced it with a new one.
They also sent an owners manual and a cable lock for it.
I'll come back with a range report when I shoot it.

[p99guy]

Sarge, you no doubt purchased six Models 500's 20 years ago...but you certainly didnt purchase Model 590A1's- they arent THAT old.

[Sarge]

p99guy Sarge, you no doubt purchased six Models 500's 20 years ago...but you certainly didnt purchase Model 590A1's- they arent THAT old.

They were 590-A1's for certain- long mag tube, heavy barrel, ghost-ring sights and metal triggerguard and safety button. We got them from a LE supplier and I specifically recall ordering 590s. I know what they were because I zeroed every one of them. I may be off by a year but this would have been no later than late 1992. The office-holder who approved them was gone that November.

Don't know where you are getting your info but by googling around a little, I can find references to the 590-A1 from late 80's, purportedly after the Navy requested heavier barrels because standard barrels were getting dented on-ship.

[Ryder]

Get the one with the bead sight like I did and your slugs will be hitting 2 feet high at 30 yards

[Sarge]

I must have gotten real lucky with the Maverick 88 I just slapped together, then.

A slug at 25 yards, load of 00 buck at 25, and a second slug (red highlight) at 50 yards-



(Plus some birdshot thrown in, just because

[PitBull]

I have a Maverick 88, too. I've had it for quite a while and I've only tried slugs in it once and they were high and to the right at 40 yds.
It does a decent enough job with 00 buck.

[colostomyclown]

Sarge, you no doubt purchased six Models 500's 20 years ago...but you certainly didnt purchase Model 590A1's- they arent THAT old.

yes, they actually are. the civilian 590a1 models aren't but the gun has been produced on contract mil/le runs since the mid or late 80's, phasing out the 500mils and 500atp

[hogdogs]

Ryder, This may sting a little But according to the law of physics and the encyclopedia of planes, angles and screw threads I have before me... A bead sight equipped gun can not make you shoot high/low/left/right or anything.

The reasons a blade sight can "make" you shoot inaccurately with any gun are simply lacking with either a single bead or mid barrel second bead.

The blade and ghost ring sights require the alignment of a plane between to items on the gun. Both of these items have too many variable measurements to assume you won't be shooting 2 feet high.

The bead is a "point of reference" sort of like a hood ornament on the car.

All you need to realize is the way the gun shoots at a given distance considering a consistent grip, cheek weld and shoulder placement. For instance, I can hit a pie plate 60-65 yards with my 18 inch barreled mossberg 500 cyl. choke with slugs. The plate will be exactly touching the top of the barrel and the bead will show inside the edge. For 50 yards, the plate is on top of the bead.

For thirty yards, there will be around 3/4 inch of daylight between the plate and barrel. You make the adjustments. And remember the gun has to accommodate so many loads and distances. A slug is lethal out to a hundred yards and they kill a bunch of deer every year but the same gun is just as accurate at 10 yards when you compensate as you must. You just have to know your gun these varying distances.

Brent

[jackblack73]

Get the one with the bead sight like I did and your slugs will be hitting 2 feet high at 30 yards

I'm new to shotguns, so when I first shot my 18.5" 590A1 I was shooting extremely high too. I found it was uncomfortable to get a low enough cheek weld and sight picture with the bead. I finally decided to install a set of ghost ring sights, not just because of the more precise sighting system, but because the ghost ring is slightly raised off the receiver and more comfortable and natural to use.

[Sarge]

Ryder, This may sting a little But according to the law of physics and the encyclopedia of planes, angles and screw threads I have before me... A bead sight equipped gun can not make you shoot high/low/left/right or anything.

Oh, but they can and do affect the elevation of your POI with slugs, particularly between 25 and 75 yards. That is precisely the reason you will see some bead-sighted riot guns with a platform or ramp under the bead. I've had issued scatterguns--always w/o that ramp--that shot a foot and a half high at 50 yards.

I suspect this relates to the amount of taper in the barrel, but cannot state that as undisputed fact. I also suspect most manufacturers eventually figured this out and have adjusted accordingly.

The bead on the aforementioned Maverick is fairly tall by shotgun standards, stepped, and it has a very small bead on top. The above target was shot using only that tiny bead showing above the center of the sighting plane on the receiver. Had I just thrown the gun up and held the whole bead up, my 50 yard shot would have been high, maybe over the shoulders.

[Ryder]

There's a big step down from the receiver to the barrel. I center the bead on the receiver using it as a rear sight. Haven't measured it yet but that step down is likely close to a quarter inch. Would be less of a factor on a long barrel, mine's only 18".

The gun hits dead on if I shoot instinctive so it's not a pressing issue but I'll probably raise that bead eventually.

[Dave McC]

Sarge has it right. Beads mounted directly to the barrel oft cause slugs to shoot way high from POA. A base under the bead is a quick fix. Or, use Kentucky elevation.