Navy 12 SxS shooting left of center

[Trapperscott]

Hello everyone. I have been lurking around here for a while and done a lot of reading. A wealth of knowledge is in these pages. I've learned a lot. But, I have a problem that I don't know how to correct and haven't seen anything written here about it.

I just came into possession of a Navy arms 12 ga SxS shotgun. According to the date code it was made in 1979. It is choked cylinder and cylinder. I have worked up a load for it in both barrels for turkey hunting this spring. But, there is a catch. At 30 yards, it shoots the center of the pattern about 7-8 inches to the left. That's with both barrels. Not quite sure how or if it can be corrected.

My load for this shotgun is 80 gr of 2F Goex, a 1/4 inch felt wad, 1 3/8 of copper plated 6's, and an over shot card. It will not have any problem taking a tom out to 30 yards. If I can remember to aim just a little right.

I am pretty handy with my hands if a fix can be found. I have been a custom knife maker for the last 22 years. I have a full machine shop here at home. Not much I can't do. Just not sure which way to attack this.

Does anyone have any suggestions for getting it to shoot a little bit to the right?

 

[matt denison]

That's not too bad really. Count your blessings.

Aim 7-8" right at 30 yards.

 

[larry wv]

I would rig up a simple rear sight right of center line on the barrels. Or move the front bead to left. If it had a big bead maybe file one side of it down.

Larry

 

[Britsmoothy]

Hi :hatsoff:

Is the stock encouraging your eye to stay to the left?
Your eye, the rear sight, can it be moved right by a little reworking the stock comb?

As both barrels shoot left, it sounds like a stock/fit issue, maybe!

B.

 

[Golfswithwolves]

Take a step to the right.

 

[Trapperscott]

I would rig up a simple rear sight right of center line on the barrels. Or move the front bead to left. If it had a big bead maybe file one side of it down.

Larry

Larry, thank you for your reply. I had thought of building an ultra small rear sight for it. Just hate to ruin the lines and look of this beautiful shotgun. But that certainly is an option. What I had not thought of that you suggested is filing the side of the front bead. As the bead should be easily replaced, I think that's what I am going to try first.

Thanks for the help Larry. I'll report back here with any results I get.

Scott

 

[Britsmoothy]

Take a step to the right.

Sorry??

 

Hi :hatsoff:

Is the stock encouraging your eye to stay to the left?
Your eye, the rear sight, can it be moved right by a little reworking the stock comb?

As both barrels shoot left, it sounds like a stock/fit issue, maybe!

B.

Agree 100%.
Decades ago some of the guys on the trap line at Friendship were steaming the stocks on originals and actually bending cast-off into them.
I would think (don't know, just think) that it might be possible to file and shim the female part of the hooked breech to move the point of aim where you want. Maybe just alter the inletting of the tang a smidgen.
You might try a strap-on cheek piece and see if that alters how you are sighting the gun.
On single barrel smooth bores I just bend the barrel but that probably wouldn't work with a double barrel.

 

[majg1234]

since you know where she shoots just apply "KY windage" :hmm: as far as the bead goes I replaced mine on my CVA several years ago as it was off the gun when I bought it.Tried at least 6-8 different ones never found a fit,so I retapped the hole to a known pitch and got one to fit.They are fine shooting guns enjoy :thumbsup:

 

[excess650]

Britsmoothy is correct. You need cast-OFF so as to move your eye further to the right.

I lowered and thinned the comb of a double that I have so as to make it shoot POA at 25 yards with a roundball load. I really didn't want to add (rifle) sights in that I wanted to be able to shoot it instinctively rather than searching for sight picture.

I also found that as I increased velocity with my roundball load, POI moved up and right. That much velocity increase may or may not blow holes in your patterns.

Have you checked for penetration of your 80gr ffg 1-3/8oz load? Your powder charge seems light for that shot charge.

 

[Trapperscott]

since you know where she shoots just apply "KY windage" :hmm: as far as the bead goes I replaced mine on my CVA several years ago as it was off the gun when I bought it.Tried at least 6-8 different ones never found a fit,so I retapped the hole to a known pitch and got one to fit.They are fine shooting guns enjoy :thumbsup:

Replacing the bead would be no problem. I am going to try filing it first to see if that brings it to POI.

But, upon looking at it closely this morning, it appears that the barrels were sawed/finished at an angle. Looking down at the barrels from the top, it appears that they were finished long on the right side to short on the left side. Haven't put a square or angle gauge on it yet, but will in a bit. I'm sure that can't help it. Kinda like the crown on a rifle barrel being not square. This might explain why both barrels shoot to the left.

Thoughts?

 

[excess650]

I can't imagine that having the muzzles finished crooked would HELP anything. Certainly check them with a square. If they are "out", squaring them can't hurt.

 

[Trapperscott]

Britsmoothy is correct. You need cast-OFF so as to move your eye further to the right.

I lowered and thinned the comb of a double that I have so as to make it shoot POA at 25 yards with a roundball load. I really didn't want to add (rifle) sights in that I wanted to be able to shoot it instinctively rather than searching for sight picture.

I also found that as I increased velocity with my roundball load, POI moved up and right. That much velocity increase may or may not blow holes in your patterns.

Have you checked for penetration of your 80gr ffg 1-3/8oz load? Your powder charge seems light for that shot charge.

I was concerned about penetration of it also. Yesterday I shot a metal tuna can at 30 yards. It was hit by 8 pellets. 7 penetrated, 1 did not. It appears that it's going to be ok.

As I am new to BP shotguns, would you think that my elementary penetration test would be sufficient? Seems like I read about using a tuna can or some other metal can as the test for penetration.

 

[Trapperscott]

I can't imagine that having the muzzles finished crooked would HELP anything. Certainly check them with a square. If they are "out", squaring them can't hurt.

Kinda what I was thinking. I will check it after I get done with coffee and get to the shop in a bit.

If it is out of square as much as it appears to be, I think it will be an easy fix for me with the tools I have.

Seems like half the fun of getting a gun to shoot is the tinkering with it.

 

[excess650]

The steel can penetration test seems to be the standard.

My own BP shotgun is a 12 bore single, and I've loaded up to 4-1/2 drams with equal volumes of shot and it didn't harm the patterns.

Your powder is just under 3 drams (85gr).

 

[excess650]

Agreed, tinkering is much of the fun. Your loading is similar to mine. I use a pair of 1/8" wonder wads over the powder and a single over shot card. I also form "shotcups" from brown grocery bags around a dowel so as to insulate the shot from the bores.

 

[Trapperscott]

Agreed, tinkering is much of the fun. Your loading is similar to mine. I use a pair of 1/8" wonder wads over the powder and a single over shot card. I also form "shotcups" from brown grocery bags around a dowel so as to insulate the shot from the bores.

I've been wanting to try making some "shotcups" out of grocery bag. Just haven't got around to doing it yet. But will.

 

[Britsmoothy]

As you have described you muzzles for lack of squareness is quite normal. A normal practice for regulating double barrelled guns. In fact as you described them and you square them I forecast they will shoot more to the left!
You are assuming and may well undo some regulation work!

 

[Britsmoothy]

As you have described you muzzles for lack of squareness is quite normal. A normal practice for regulating double barrelled guns. In fact as you described them and you square them I forecast they will shoot more to the left!
You are assuming and may well undo some regulation work!

 

[Grenadier1758]

I agree with BritSmoothie.

There has been some sort of attempted regulation done. The shorter left side means the shot wads exit on the left side first and the escaping gases will push the pattern to the right. You may need to take more off the left side to push the POI to the right.