First off, I like the pattern. Allows for a bit of cushion for wind catching a target, or erratic flight of live birds. I understand you are not used to this.
Number of things come to mind. Gun fit on this gun compared to SKB, the choke itself, and how this gun patterns other loads, factory loads.
Quite a few trap shooters, use a trap gun that does shoot higher for everything, including skeet, hunting , general purpose. Just one has to get used to the gun, and POA/POI.
Gun specs are going to differ, I'd take a good look on how you mount and the guns fits between the two. Do you shoot pre-mount, or low gun?
I'd get a box of factory loads, both guns, and at 21 yards, from low gun, fire two shots.
Just focus on the dot on the pattern paper, mount gun to face and shoot two.
Sometimes if one walks up, like they would bird hunting, stop at the same line, and mount gun to face, and shoot two - reveals some things that just standing with intent of shooting for a pattern does not.
Using the factory loads, with both guns, will give a baseline.
Then repeat with your factory loads. Some guns like some loadings better than others.
I am assuming this Browning has screw in chokes. Browning chokes are good chokes - (some other brand chokes had some problems not being concentric, which will throw off POA/POI) - that said, chokes are like barrels, they have preferences on loads. So you could put in another choke (Skeet, IC , Mod, Full) and see what this gun does with them - not going to hurt to have this notated anyway.
For instance, with factory Rem chokes, I have shot the same gun, using 3 different IC chokes, and gotten 3 different POA/POIs , not concentric. Using an after market choke - got the POA/POI like this person wanted it.
I doubt the Browning choke is off...still with a baseline, if you have another choke or had friends with same guns and tried their chokes, that would alleviate that variable.
Heck shoot their guns if like yours...might be little detail in specs, fit, something.
Nice gun, nice gauge! Just remember, there is difference in how one mounts and shoots between platforms. Even if these guns fits, shoot POA/POI - changing from one to another, can - and will affect where the shot goes compared to where pointing.
A number of folks got to shooting gas guns in 12 ga, then transitioned to O/U for 20, 28 and .410 using barrel sets. Going from a repeater, to a O/U gave them fits. The guns fit, the pattern board revealed the guns shot as they were supposed to, just the shooter was changing platforms.
This is why a lot of folks went to shooting the 20 ga in 12 ga events. They stayed with the O/U platform , using 20, 28, .410 with the 3 barrel sets. Heck quite a few shot 28gauge, for the first three events, and then had to change barrels for the .410 event.
Why Tube sets are used so much. Use the same gun for everything, just change tubes, gauges for events.
In the old days,and folks still do, they had 4 guns, alike, in all 4 gauges. 1100s, and 870s for example. 1300s were made in 28 and .410 back then, and of course Model 12 for first three events, model 42 in .410 for the fourth event.
Just like we our shoes fit us, there is a difference in our tennis shoes, dress shoes, boots...
Shoes make a difference. I suggest folks shoot in the same shoes, when shooting skeet for scores. I prefer a bit of forward lift.
One can shoot the same gun, same load, shoot the same pattern board, at the same distance.
Wear 3 different kind of footwear - and get different POA/POIs
I'm serious. Put on some flat shoes like boat shoes, shoot, try on your tennis shoes with forward lift, shoot, and then try boots ( folks should shoot in hunting boots to know and be familiar anyway) or just tape cardboard on the bottom of these forward lift to give more lift and shoot.
Our body positioning changes. Footwear can, and does affect the total body posture, how muscles, skeletal and everything lines up. If we do not "line up" the same way each time, the gun is to "fit different" each time.
I have folks do as I did, wear the same shoes they shoot in - to do repetitions of mounting gun to face.
Ingraining these correct basic fundamentals are important, so doing 25 or more each night, correctly, with the same shoes, and all one shoots in, get all this muscle memory, human computer and all trained right. Once we get it, and we keep practicing it - we are better at letting the human computer do for us, in adapting to changes. We just have to get all this programmed correctly first.
Many folks get to where they are more erect when they shoot, lessens muscle tensions, lessens fatigue. We have all seen Skeet shooters "scrunched" and "contorted" when they shoot. Fine, if that is what they want to do, just puts more stress on the body, and they start out fine and strong, and about the 3 rd box start missing birds.
I stand erect, some say more than some trap shooters do. Trap shooters are shooting a different presentation, still many trap shooters shoot skeet, 5 stand, sporting clays, hunt...and they are one with the gun...it shoots a bit higher, but they know this, and use it to their advantage.
I prefer a field gun, that shoots for me a bit high. I am wanting to shoot "real world" like live game, or any defensive training. I was not taught to shoot program birds. Never. So the way I was taught, and how my Mentors shot just a natural , more erect stance with gun fit, pattern board checked out, and shoot. Did not matter if a skeet target or not. Machines were were not always regulated, and I was not advised if throwing , high or low.
I didn't call for bird either - they pulled, I shot. Just like real world. From low gun.
Take my gun and add tape something to comb or add moleskin. Sometimes a lot. Now I did not get to pattern my gun, and I did not know what the heck kind of load I had. I was not allowed to pattern gun.
"Shoot two, always shoot two" . This made sure safety was off, and I was to pay attention to the "pattern" at the grass or whatever background. Just pick a weed, bare spot, flower and shoot two.
Now...they they would toss a target, I did not call for, and who knows how the machines were set to throw.
I would have to read the breaks on the targets and "just shoot the durn gun, focus on target, still just shoot the durn gun"
I started young with correct basic fundamentals, gun fit, pattern boards ( stationary and moving pattern boards) and repetitions every night, wearing shoes and gear I shot in for scores.
Mentors then "gonna step this up a notch, and keep stepping it up"
Yeah well they could told me that danged old trap stock was sporting a full choke trap barrel , instead of the IC barrel ...it did seem a bit longer than a 26" IC, just they hurried this up and my brain said when shooting two " humm a bit tighter pattern there out yonder" and then they tossed targets real fast, just barely giving me time to load the gun, as I moved station to station.
Fifty shots, I did not get off station 8 the first time good " get your butt on Station 1, gonna do it again".
"You missed 4 birds, not bad, just not good enough...gotta practice more if you want it, and want it bad". 46/50 with a full choke trap gun...
Now get me out on field shooting for scores, with my loads that shot POA/POI, with my gun that fit, with the regulated targets - piece of cake.
Rain, wind, snow, sleet, hot humid south, even a tornado...all this paid off. Fair weather shooters on the porch , I was shooting, and it made no difference what the weather was doing to birds..."If you see 'em - you can fell 'em"
"We want you young' un -where just hand you a gun, some ammo and just shoot the durn thing".
I am so very grateful for these Mentors - I miss 'em, and they were so right!
Pattern boards - are sitting still. One shoots different when the birds are flying, adrenalin flowing , and everything else in how they mount and shoot.
Even the same gun five years later may change on someone. Body changes, weight loss/ gain , even just age, with muscle, tissue, fat, bone structure. The gun that fit, and shot POA/POI - may need tweaking just because of age.
Art & Science.
Some of this was for the new shooters...