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MP94 Combo gun
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I have an MP94 combo gun. I like it. But it has one problem. The shotgun barrel shoots much higher than the 30-06.

Are there any good solutions to fix this?

I am gussing that this little part is designed to regulate the barrels, but there is no way to expand it.




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Posts: 588 | Registered: 16 December 2002Reply With Quote
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I'll tell you what I have heard as I have the same gun, same issue.

First pick the range you want the barrels regulated to: 50 yard, 100 yards? Then measure the vertical distance between the two patterns. Take those two measurements and then send it off with the little plug in the your picture to EAA Corp. They will make a new one to adjust the vertical dispersion.

I'd contact EAA first to make sure. I just found this out this week and have not had a chance.

I'd also recommend you dump the rear sight and put a Williams WGRS-54 sight back on the 11mm dovetail. Much improved sight radius.


Dave

In 100 years who of us will care?
An armed society is a polite society!
Just because they say you are paranoid doesn't mean they are not out to get you.
 
Posts: 899 | Location: Ammon, NC | Registered: 31 December 2013Reply With Quote
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I have the same gun with the same problem, when I first got it. I tried to work directly with customer service but they were totally useless.What you need to do is very simple. You need to increase the distance between the 2 barrels at the little cross plug.

If you look closely you will see a little spring loaded pin that holds the cap on the cross pin on one side, you need to get this cap off, then drift the cross pin out. Mine actually fell out by gravity after I got the cap off. There is a flat on both barrels where the cross pin sits. I just made small pices of shim stock, cut to fit the flat area and then drifted the cross pin back in. It was a little trial and error to determine the size of shims and I ultimately needed enough that it was difficult to get the cross pin back in. I used a super large screw driver inserted sideways between the barrels and twisted it to spread the barrels. Of course I used a rag to protect the barrel finish. I really had to twist and spread, but dont worry, you wont hurt anything. After getting all the shims in I have both barrels hitting same point of aim at 50 yards.

Also, my gun would hit in drastically different places depending on what grain rifle bullet I used, so make sure you decide on one specific ammo and then shim the cross pin for it.

Easy Peasy, Lemon Squeezy
 
Posts: 28 | Location: DFW | Registered: 03 December 2013Reply With Quote
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quote:
my gun would hit in drastically different places depending on what grain rifle bullet I used, so make sure you decide on one specific ammo and then shim the cross pin for it.


OK, I was heading down the right path.

I was thinking of getting a rubber plug with bolt, to expand the distance between the barrels.

http://ecx.images-amazon.com/i.../I/21kxXIc%2BGiL.jpg

http://www.lifeasbob.com/conte..._neoprene_rubber.jpg

Then maybe shim it once I get it corrected.


CISSP, CISA, CRISC looking for a IT Security/Audit Manager spot
 
Posts: 588 | Registered: 16 December 2002Reply With Quote
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quote:
Originally posted by drhall762:
I'll tell you what I have heard as I have the same gun, same issue.

First pick the range you want the barrels regulated to: 50 yard, 100 yards? Then measure the vertical distance between the two patterns. Take those two measurements and then send it off with the little plug in the your picture to EAA Corp. They will make a new one to adjust the vertical dispersion.

I'd contact EAA first to make sure. I just found this out this week and have not had a chance.

I'd also recommend you dump the rear sight and put a Williams WGRS-54 sight back on the 11mm dovetail. Much improved sight radius.


The sight is ok, but not great for my eyes.

So I mounted a scope 1-6x. I just pull up and there it is. The only issue is the weight. The scope throws things out of balance.


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Posts: 588 | Registered: 16 December 2002Reply With Quote
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Picture of drhall762
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quote:
Originally posted by dieselten:
I have the same gun with the same problem, when I first got it. I tried to work directly with customer service but they were totally useless.What you need to do is very simple. You need to increase the distance between the 2 barrels at the little cross plug.

If you look closely you will see a little spring loaded pin that holds the cap on the cross pin on one side, you need to get this cap off, then drift the cross pin out. Mine actually fell out by gravity after I got the cap off. There is a flat on both barrels where the cross pin sits. I just made small pices of shim stock, cut to fit the flat area and then drifted the cross pin back in. It was a little trial and error to determine the size of shims and I ultimately needed enough that it was difficult to get the cross pin back in. I used a super large screw driver inserted sideways between the barrels and twisted it to spread the barrels. Of course I used a rag to protect the barrel finish. I really had to twist and spread, but dont worry, you wont hurt anything. After getting all the shims in I have both barrels hitting same point of aim at 50 yards.

Also, my gun would hit in drastically different places depending on what grain rifle bullet I used, so make sure you decide on one specific ammo and then shim the cross pin for it.

Easy Peasy, Lemon Squeezy


Well that saved me a call to customer service. I'll just apply a little Trig and at least I'll be ball park to start.


Dave

In 100 years who of us will care?
An armed society is a polite society!
Just because they say you are paranoid doesn't mean they are not out to get you.
 
Posts: 899 | Location: Ammon, NC | Registered: 31 December 2013Reply With Quote
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If memory serves, I think I have about .025" of shims in there. I am pretty sure I posted a review on this over a year ago when I got the rifle.
 
Posts: 28 | Location: DFW | Registered: 03 December 2013Reply With Quote
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Here is my post from when I first got my gun:

I wanted to try out a combo gun for a while so I picked up a MP94 at Bud's for $475. I read all the way through this forum and others to find out how to get it shooting where I wanted. It is 12G over 30-06 and at 50 yards with iron sights the rifle barrel hit 10" lower than a rifled slug, with a scope the variance changed to 17" lower than a slug at 50 yards. The difference here is the difference between the height over bore of the irons verse a scope. It is impossible to have both barrels hit same point of aim with 2 different height sighting systems.

Next step was to determine which slug and which rifle load to use. I bought every different slug I could find and found out they all hit within 2" difference at 50 yards, so I picked a Winchester 1oz at 1600 fps. The rifle shot best with a handload of H4350 and a 180 Hornady spitzer. If I let the barrel cool all the way between shots I could put 3 shots into about an inch at 100 yards.

And the most important thing- the gun shot both barrels to the same windage, thankfully, cause that would not be easy to correct. I wanted the slugs to print between 1-2" hi at 50 yards and the rifle to be on at 100 to maybe 1" hi. I would not be shooting much past 100 with the rifle and not past 60 with a slug. So I checked the rifle at 50 with a zero at 100 and at 50 it printed .5" low. So there is my goal - shoot both barrels at 50 yards and have the slugs hit 1-2" hi and the rifle to be .5" low to dead on (at 50 yards).

I decided most of my shooting would be with a scope so I would have to accept a larger dispersion between barrels with the iron sights.

Now, the barrels were hitting 17" apart at 50, so I needed to make up between 15-16". I started by removing the wedge pin between the barrels. It came out easy as there was no tension at all on it. It was not wedging anything, just taking up space. So I called USSG and ordered some new wedges. I figured their gunsmith was probably an idiot ( and I was right) so I ordered 3 wedges. I gave them the exact dispersion between barrels and the size of the current wedge. I said send me what they thought I needed, then send me 2 more wedges even bigger. They wound up sending me 2 wedges smaller than my current wedge and one wedge slightly larger but way smaller than I needed. Total waste of time.

So i decided to cut some shim stock from a stainless steel shim kit I got from Brownells. I just cut it to fit the flats between the barrels where the wedge goes. Trial and error determined that .025" of shims in conjunction with the original wedge worked perfectly. And when all assembled you could not see the shims at all. The rifle barrel now hit dead on at 100 yards, about .5" low at 50 and the slugs hit 1" hi at 50 yards. I am ready to hunt!

The shimming process did not change the windage and both barrels still printed with the same windage. The shimming did make the rifle barrel much more sensitive to temperature, probably due to the greater stress it was under. But if I waited till it was cool between shots, they all hit very close.
 
Posts: 28 | Location: DFW | Registered: 03 December 2013Reply With Quote
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