Finally hit the pattern board today to check the POI difference between my two CZ Mallard barrels.
They are about 5.5" off at 30 yds. I'm assuming most of you wouldn't worry about, and would just hunt, I want both barrels to be dead on at 40 yds for a follow up shot, or a shot on a 2nd bird if needed. At 40 yds we're talking probably 7.5" or so, seems like a lot to give up, so I think I'll go the eccentric choke route for the bottom barrel. Tell me this isn't a waste.
CZ Mallard Barrel Regulation
Re: CZ Mallard Barrel Regulation
one shot will not be able to tell you the true difference. just bc they are 5.5" apart at 30 yd don't mean they will be further apart at 40yds. its dependent upon the angle of the barrel or barrels vs angle of the rib/bead. if that makes any sense. The barrels POI in relation to the bead may be designed for a 40 yd POI. if that is the case, then whatever the "gap" is at 30 will close down at 40. on the contrary, if both barrels are hitting the same POI at 20 and then vary from there then they will open and 30 and then more at 40 etc... but this would be in an extreme case.
what you first need to find is at what distance do both barrels have the same POI. best way to find this is bore sighting laser. get two cheap ones, the 12, 20, 28 gauge chamber inserted lasers are ok, but i prefer two cheap bushnell bore inserted lasers. you can use one and just aim out at a target at say 40 yds and see where the laser is pointed in relation to your bead, then at 30,20 etc. and take note of these sight picture vs/ laser POI point. then switch barrels and do the same.
Or buy two(preferred) insert them into your bores, go outside, and start at your feet with the lasers turned on, and begin to raise your muzzle, as you raise it , you will see the gap between the two lasers eventually come closer together at (X) distance...., that distance where the lasers are will give you a good indication of where the POI of both barrels are the same. now look down your rib and bead and see where that point is in relation to your bead...
NOw, if the gap still exist, and lets say the gap really is 5.5" at 30 yds. that may not be ideal, but would 2.75" be better? theres a way to make that happen without going the eccentric choke route. Once you have that spot marked, you will want to know which barrel is the high barrel and which barrel is the low... Im gonna go on a wild hair and say the top barrel is the high barrel... if this is the case, and your bead is lined up dead on the POI of the top barrel, in order to split the difference. you will need a tad higher POI on that top barrel, this is and EASY fix! raise your head thats it! put a piece of tape on the stock, leather, moleskin, baseball bat grip tape or anything, it will change your sight picture but in turn, split the difference between the two points of impact at said yardage.
and THEN, lets say the you have split the difference and made the POI in relation to the laser higher at 20 or 30 yards, keep in mind your dealing with a laser. lasers are straight.. shot drops! so a tad high POI on the top barrel and low on the bottom barrel. is perfect! use the bottom barrel up close. and then with the added drop of the shotshell. that distance you just split raising the POI of the top barrel should have you on the money at 40, 50 etc...
This probably don't make a lick of sense. I will try to pull out one of my O/U and see if i can take some pictures and give you an idea of what i mean. but eccentric chokes... for the birds.
what you first need to find is at what distance do both barrels have the same POI. best way to find this is bore sighting laser. get two cheap ones, the 12, 20, 28 gauge chamber inserted lasers are ok, but i prefer two cheap bushnell bore inserted lasers. you can use one and just aim out at a target at say 40 yds and see where the laser is pointed in relation to your bead, then at 30,20 etc. and take note of these sight picture vs/ laser POI point. then switch barrels and do the same.
Or buy two(preferred) insert them into your bores, go outside, and start at your feet with the lasers turned on, and begin to raise your muzzle, as you raise it , you will see the gap between the two lasers eventually come closer together at (X) distance...., that distance where the lasers are will give you a good indication of where the POI of both barrels are the same. now look down your rib and bead and see where that point is in relation to your bead...
NOw, if the gap still exist, and lets say the gap really is 5.5" at 30 yds. that may not be ideal, but would 2.75" be better? theres a way to make that happen without going the eccentric choke route. Once you have that spot marked, you will want to know which barrel is the high barrel and which barrel is the low... Im gonna go on a wild hair and say the top barrel is the high barrel... if this is the case, and your bead is lined up dead on the POI of the top barrel, in order to split the difference. you will need a tad higher POI on that top barrel, this is and EASY fix! raise your head thats it! put a piece of tape on the stock, leather, moleskin, baseball bat grip tape or anything, it will change your sight picture but in turn, split the difference between the two points of impact at said yardage.
and THEN, lets say the you have split the difference and made the POI in relation to the laser higher at 20 or 30 yards, keep in mind your dealing with a laser. lasers are straight.. shot drops! so a tad high POI on the top barrel and low on the bottom barrel. is perfect! use the bottom barrel up close. and then with the added drop of the shotshell. that distance you just split raising the POI of the top barrel should have you on the money at 40, 50 etc...
This probably don't make a lick of sense. I will try to pull out one of my O/U and see if i can take some pictures and give you an idea of what i mean. but eccentric chokes... for the birds.
Last edited by OneShot on February 12th, 2017, 3:59 am, edited 1 time in total.
Re: CZ Mallard Barrel Regulation
Maybe this will help a bit w/ my previous explanation. In these pictures, their is a laser in both barrels and they are pointed out across the yard onto a fence pole at 30 yds. there is about a 5" gap between point of impact between both barrel on the vertical pole at 30 yards. In one picture you will see where POA and POI are the same for the top barrel, resulting in the bottom barrel shooting 5" low considering the same hold point, and another picture where POA and POI are the same for the bottom barrel, again considering the same hold point when the top barrel is fired POI will be 5" high. In the other you will see where the difference is split. resulting in the impact from both barrels in relation to hold point being 2.5" high (top barrel) and 2.5" low (bottom barrel), keep in perspective, THE BEAD ON YOUR SHOTGUN COVERS AT LEAST 2" at 30 yds...
Ive put several O/U on paper, from low end to high end, from yildiz, to citoris and 69X berettas, up to Kolars and Kreighoffs. Enough to where I would Almost bet my unborn first born son on saying that 5" gap at 30 will be no more that a 5" gap at 40.
so hypothetically speaking,lets say you have successfully moved your POA directly in the middle of your two POI's, and lets say your gun is throwing a 10" pattern at 30 yds. lets say your target is a 2" circle at 30 yards, and your bead is covering 2" circle at 30 yards. You center that bead smack dead in the center of your 2" circle target covering it. It doesn't matter which barrel you shoot, that 2" circle lies smack dab in the center of the top 50% of the bottom barrels pattern and bottom 50% of the top barrels pattern.... shoot the bottom barrel, he dead. another one beside it, follow up with top barrel he dead.
same thing at 40, bead size covering the target increases, pattern also increases, he still dead either barrel. now you got on out there at 50 or 60 yards where a little drop, not much but a little, from what I've tested, TSS 9's @ 1200 fps give me a 5" drop at 70 yards when zeroed at 40, so your going to be less than that drop wise lets say 2" @ 50 3" at 60... your beads covering more than that! so you can either shoot top barrel first and bump that hold point up a hair and sit that bead on top of his head or, you can switch that barrel selector over and then shoot top barrel and use the same hold dead on his head like you've been doing at 30 and 40 and thats gonna put that shot dead on the money. (this is IF your brain is able to tell you to do this in the heat of the moment)
with that being said, you shoot one bird at 25 yds bottom barrel first, the second bird your trying to shoot is skipping town, he's gonna be moving, he gets on out there 45,55, 60 yards, you take that second shot with the top barrel coving his head, its on the money at that distance, whereas if you were shooting an auto or a pump you would have to tell your brain, he's a little further out, hold a hair high... that would be using two barrels having two different POI to a positive advantage.
So there's what the "numbers" say, heres what reality says, in the event having a chance to shoot a second bird, or having to get off a quick follow up shot, running shot, or you bust his flipper all up and your running him down in a pine thicket like Jeremiah Johnson to finish the job.... you have to ask yourself... can I hold a bead thats covering 3" @ 40 to a 2.5"+- tolerance while runnin and gunnin. If you can stop hunting and start shooting sporting clays, There will be a company out there very quickly that will hand you a T-shirt and a shotgun with their name on it and all the shells you could ever ask for.
No Bead(How I like it!!) , aiming flat down the rib. Notice two red dots top and bottom barrel.
With the bead on, aiming flat down rib it gives a perfect 50/50 Split between the top and bottom barrel POI's
Head raised, gives you dead on with the bottom barrel, high w/ the top barrel (Seeing more rib)
Head down into the comb, dead on w/ top barrel, Lower POI w/ bottom barrel. (seeing more of the back of the gun)
Ive put several O/U on paper, from low end to high end, from yildiz, to citoris and 69X berettas, up to Kolars and Kreighoffs. Enough to where I would Almost bet my unborn first born son on saying that 5" gap at 30 will be no more that a 5" gap at 40.
so hypothetically speaking,lets say you have successfully moved your POA directly in the middle of your two POI's, and lets say your gun is throwing a 10" pattern at 30 yds. lets say your target is a 2" circle at 30 yards, and your bead is covering 2" circle at 30 yards. You center that bead smack dead in the center of your 2" circle target covering it. It doesn't matter which barrel you shoot, that 2" circle lies smack dab in the center of the top 50% of the bottom barrels pattern and bottom 50% of the top barrels pattern.... shoot the bottom barrel, he dead. another one beside it, follow up with top barrel he dead.
same thing at 40, bead size covering the target increases, pattern also increases, he still dead either barrel. now you got on out there at 50 or 60 yards where a little drop, not much but a little, from what I've tested, TSS 9's @ 1200 fps give me a 5" drop at 70 yards when zeroed at 40, so your going to be less than that drop wise lets say 2" @ 50 3" at 60... your beads covering more than that! so you can either shoot top barrel first and bump that hold point up a hair and sit that bead on top of his head or, you can switch that barrel selector over and then shoot top barrel and use the same hold dead on his head like you've been doing at 30 and 40 and thats gonna put that shot dead on the money. (this is IF your brain is able to tell you to do this in the heat of the moment)
with that being said, you shoot one bird at 25 yds bottom barrel first, the second bird your trying to shoot is skipping town, he's gonna be moving, he gets on out there 45,55, 60 yards, you take that second shot with the top barrel coving his head, its on the money at that distance, whereas if you were shooting an auto or a pump you would have to tell your brain, he's a little further out, hold a hair high... that would be using two barrels having two different POI to a positive advantage.
So there's what the "numbers" say, heres what reality says, in the event having a chance to shoot a second bird, or having to get off a quick follow up shot, running shot, or you bust his flipper all up and your running him down in a pine thicket like Jeremiah Johnson to finish the job.... you have to ask yourself... can I hold a bead thats covering 3" @ 40 to a 2.5"+- tolerance while runnin and gunnin. If you can stop hunting and start shooting sporting clays, There will be a company out there very quickly that will hand you a T-shirt and a shotgun with their name on it and all the shells you could ever ask for.
No Bead(How I like it!!) , aiming flat down the rib. Notice two red dots top and bottom barrel.
With the bead on, aiming flat down rib it gives a perfect 50/50 Split between the top and bottom barrel POI's
Head raised, gives you dead on with the bottom barrel, high w/ the top barrel (Seeing more rib)
Head down into the comb, dead on w/ top barrel, Lower POI w/ bottom barrel. (seeing more of the back of the gun)
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MeadowCreekMounts
- Posts: 392
- Joined: March 17th, 2014, 2:07 pm
Re: CZ Mallard Barrel Regulation
I understand everything you're saying, however the gap is larger at 40 yds than at 30. 30 yds was chosen because that is the routine that Briley has you follow so that they know how to cut the chokes. Firing 3 shots with each barrel (I actually did the test 2 different times for a total of 12 shots) yields the same results. At 40 yds the spread is more like 8-10". Splitting the difference just is not for me, my sights will be dead on with the top barrel if I hunt with it. I appreciate the input and will certainly try the lasers just to see what I get.
Re: CZ Mallard Barrel Regulation
Great explanation...for wing/trap/skeet shooting, but that amount of variance is enough to matter to a turkey hunter shooting a tightly choked load of TSS and using a dot or reflex sight. At 40 yds I only have 8 inches of wiggle room either way to cause a complete miss and I want to start with the poi centered on my target as much as possible to allow for my wiggles.
Also, he didn't say it was off by one being higher than the other; could be one is to the left or right of the other.
Also, he didn't say it was off by one being higher than the other; could be one is to the left or right of the other.
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01Foreman400
- Posts: 431
- Joined: March 4th, 2013, 3:33 pm
Re: CZ Mallard Barrel Regulation
This is the reason I'm reluctant to do another O/U turkey gun project.
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Gar Commander
- Posts: 377
- Joined: February 26th, 2013, 6:52 pm
Re: CZ Mallard Barrel Regulation
Ditto on that reluctancy to set up another O/U here also.
Re: CZ Mallard Barrel Regulation
8-10" is extreme, but I have seen worse, almost double that, out of a Luxus F3, needless to say that gun got sent back to Blaser. Over the phone when he told them it was a ft. and half high at 20 yds they thought he was crazy. When they got the gun and shot it they called him back and said wow you wasn't joking, not only did it get re-barreled but also had the triggers and receiver were converted to the newer generation at no cost...
Im not trying to stray you away from the eccentric choke bc I'm on the same page with both of you, I was big into long range shooting and guns and reloading for those guns, and a half inch might as well be a mile, a tenth grain might as well be a lb. Just throwing a thing or two out there to think on before you send it off
Have you put the choke that is in the top barrel (and hitting where you like it) into the bottom barrel to seen where it hits and vise versa bottom to the top. That will also be a good indicator to tell if the bottom barrel choke is a dud and thats whats throwing you 8-10" off, or if the bottom barrel or threads are whats really out of alignment.
Im not trying to stray you away from the eccentric choke bc I'm on the same page with both of you, I was big into long range shooting and guns and reloading for those guns, and a half inch might as well be a mile, a tenth grain might as well be a lb. Just throwing a thing or two out there to think on before you send it off
Have you put the choke that is in the top barrel (and hitting where you like it) into the bottom barrel to seen where it hits and vise versa bottom to the top. That will also be a good indicator to tell if the bottom barrel choke is a dud and thats whats throwing you 8-10" off, or if the bottom barrel or threads are whats really out of alignment.
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RapscallionVermilion
- Posts: 484
- Joined: February 17th, 2013, 4:24 pm
- Location: New Mexico
Re: CZ Mallard Barrel Regulation
Briley made me an eccentric choke for a Beretta O/U some years ago. It did work just fine and the process with Briley went very smoothly. That gun was off 8" vertically at 30 yards. If you were to go that route, I would look at doing the eccentric choke on the barrel you plan to have the more open choke in, as long as it isn't too open, which would be unlikely in a turkey gun anyway. When Connecticut Shotgun came out with their SxS slug gun, they incorporated an adjustable barrel regulation system. That would be cool on a turkey gun.
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Southern Sportsman
- Gobbler Nation
- Posts: 1314
- Joined: February 24th, 2013, 12:32 am
- Location: West TN
Re: CZ Mallard Barrel Regulation
X3. I sold mine for just this reason. It's a great concept, and if you get lucky or spend enough to get perfectly alligned barrels, it's awesome. But mine was not.Gar Commander wrote:Ditto on that reluctancy to set up another O/U here also.
I go stubbornly into error by myself, and reach my own fallacious conclusions using my own faulty data. ~Tom Kelly
Re: CZ Mallard Barrel Regulation
I've sent an O/U to Briley for regulation correction before. They re-threaded the barrels and put it spot on. There was a little back and forth to convince them regulation should be spot on for windage at around 15 yards, but they did it. And it was for free, because they do Yildiz for free. Yildiz is the only O/U I'd consider for turkeys because of the ability to get it corrected by calling Briley and dropping it off at Academy. Hang paying real money for a gun and having it be too far off.
This last O/U I've been using is on for windage, but about four inches low. I like it because I get to aim at the head and not worry about missing high. I've killed about a half dozen with it and only missed once. It was a snap shot at 20 yards on a spooked bird. Took my time and got him with the bottom barrel at about 35 yards.
This last O/U I've been using is on for windage, but about four inches low. I like it because I get to aim at the head and not worry about missing high. I've killed about a half dozen with it and only missed once. It was a snap shot at 20 yards on a spooked bird. Took my time and got him with the bottom barrel at about 35 yards.
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MeadowCreekMounts
- Posts: 392
- Joined: March 17th, 2014, 2:07 pm
Re: CZ Mallard Barrel Regulation
I've shot a few chokes in both barrels to get an idea on patterns so that I knew if I even wanted to monkey with this gun. I've ran probably 50 shells through it, I didn't just slap something in it and go outside and fire 2 shots and think it was off.OneShot wrote:8-10" is extreme, but I have seen worse, almost double that, out of a Luxus F3, needless to say that gun got sent back to Blaser. Over the phone when he told them it was a ft. and half high at 20 yds they thought he was crazy. When they got the gun and shot it they called him back and said wow you wasn't joking, not only did it get re-barreled but also had the triggers and receiver were converted to the newer generation at no cost...
Im not trying to stray you away from the eccentric choke bc I'm on the same page with both of you, I was big into long range shooting and guns and reloading for those guns, and a half inch might as well be a mile, a tenth grain might as well be a lb. Just throwing a thing or two out there to think on before you send it off
Have you put the choke that is in the top barrel (and hitting where you like it) into the bottom barrel to seen where it hits and vise versa bottom to the top. That will also be a good indicator to tell if the bottom barrel choke is a dud and thats whats throwing you 8-10" off, or if the bottom barrel or threads are whats really out of alignment.
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MeadowCreekMounts
- Posts: 392
- Joined: March 17th, 2014, 2:07 pm
Re: CZ Mallard Barrel Regulation
That's exactly what I'm doing. The top barrel is my "40 yard" barrel and the other is the close up, spreader with a LeadxTSS duplex load. I still want the bottom barrel to be sufficient at 40 yards, that's why I want them to both his the same at 40 yards. There is a lot of wiggle room up close with that load, but I need it to be pretty dead nuts at 40 to be sufficient.RapscallionVermilion wrote:Briley made me an eccentric choke for a Beretta O/U some years ago. It did work just fine and the process with Briley went very smoothly. That gun was off 8" vertically at 30 yards. If you were to go that route, I would look at doing the eccentric choke on the barrel you plan to have the more open choke in, as long as it isn't too open, which would be unlikely in a turkey gun anyway. When Connecticut Shotgun came out with their SxS slug gun, they incorporated an adjustable barrel regulation system. That would be cool on a turkey gun.
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MeadowCreekMounts
- Posts: 392
- Joined: March 17th, 2014, 2:07 pm
Re: CZ Mallard Barrel Regulation
They don't have a dual trigger O/U though, right?howl wrote:I've sent an O/U to Briley for regulation correction before. They re-threaded the barrels and put it spot on. There was a little back and forth to convince them regulation should be spot on for windage at around 15 yards, but they did it. And it was for free, because they do Yildiz for free. Yildiz is the only O/U I'd consider for turkeys because of the ability to get it corrected by calling Briley and dropping it off at Academy. Hang paying real money for a gun and having it be too far off.
This last O/U I've been using is on for windage, but about four inches low. I like it because I get to aim at the head and not worry about missing high. I've killed about a half dozen with it and only missed once. It was a snap shot at 20 yards on a spooked bird. Took my time and got him with the bottom barrel at about 35 yards.
Re: CZ Mallard Barrel Regulation
Don't think so. All the ones you can get are on Academy's web site.
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Gar Commander
- Posts: 377
- Joined: February 26th, 2013, 6:52 pm
Re: CZ Mallard Barrel Regulation
the only way I would buy another O/U would be if it was where the seller would let me shoot it before buying it. I realize it would probably have to be a used gun to do this, but that is where the best deals on them are usually found.
Re: CZ Mallard Barrel Regulation
You guys may have swayed me from my o/u 20 gauge I was planning on? For me I would be fine with the top barrel on and compensating with the bottom with a more open choke/load
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