What difference should I expect between 1 1/8 oz @ 1200fps or 1 oz @ 1300fps?

In a properly choked gun, 1 1/8 ounce will occasionally get you an extra target.

I think better breaks especially further out.

Edit - just realized this is in skeet forum. Wouldn’t shoot either of those at skeet. Yikes!

Neither! 1oz @ 1200fps. Recoil is your enemy is this game!! Lower recoil will let you execute your fundamentals better like staying on the gun and have control after the shot with your follow through. Those are key to more and better breaks. 1oz is more than enough considering most of the best skeet shooters don't shoot anything bigger than a 20ga. Also you don't need anything other than .005 skeet chokes or faster than 1200fps on a skeet field

Understood, but my current purchase choices are the ones mentioned, hence my question.

None.

1 1/8oz @ 1200fps

Buy #9s.

585 - 1 oz #9
410 - 1 oz #8
658 - 1 1/8 oz #9
461 - 1 1/8 oz #8

My pick as well given your options.

The only advantage 1 ounce loads hold over 1 1/8 ounce loads is less recoil. But at 1300 fps those 1 ounce loads will not have less recoil.

If you google it, you will probably find recoil charts. I know Paul Giambrone shoots 20 gauge in 12 gauge events; then again Philip Streleu, who wins most of the shoots at Missoula Trap and Skeet, shoots 1 1/8 12 gauge.

I think Shima and Mayes shot 12 gauge, but they used semi-autos.

I am curious to know what gauge Mike Schmidt uses. I believe he holds the record for most consecutive 12 gauge targets.

Randy

That was in the back of my mind . . wondering if the additional 100fps for the 1oz loads was the result of the same powder/pressure charge simply pushing a lighter load faster, and therefore no change or perhaps even a little less recoil resulting from the push against less resistance from the lighter load. That seems logical to me but doesn’t seems to be the reality that most people are reporting.

I don't know what you think most people are reporting, but higher velocity means more recoil, just like a larger payload. An extra 100 fps will generate more recoil. That extra velocity in American skeet is worthless. Given your restrictions, the 1200 fps 1 & 1/8 shell probably does make more sense for skeet. I still think 1 ounce of 9s at 1200 fps is the best skeet shell, but we didn't have that choice. I hope you are able to put all the shell and choke thoughts out of your head when you get back to shooting.

Yes they will, but only slightly.....remember that recoil is a function of the Product of charge weight and velocity....

1200 x 1.125 = 1350

1300 x 1.000 = 1300

So the 1 1/8 oz loads would have slightly more recoil.

Mike has shot 12 in a 390/391 and 20 or 28 in his Krieghoff when I have shot with him.

When Mike set the 12ga long run mark he was 12ga 390/391. A couple of years ago he was limited to 28ga do to eye problem however for the 2020 world championship which he won, he was back to the auto loader

because 4 gun skeet has become so intertwined, shot payload and recoil doesn't really matter.
now....if skeet went to the rules used in rifle or pistol matches, where payload, gun type, or modifications were limited, I'd bet my bottom dollar people would be paying attention to details as to what gun, what payload, what shell, what gauge is used.
as it is....just shoot the benchmark load of 1200fps 1 1/8oz and go home knowing youre shooting a true man load.

One thing of many that I don't understand is that semi-autos have less felt recoil. My Beretta 687 with a barrel weight and Graco recoil reducer weighs almost 9 1/2 lbs. When I shot someone's Beretta A400 I was surprised at how much recoil the A400 had, certainly a lot more than my O/U.

Randy

Physics is still physics...... if your gas gun weighed the same as your O/U, then shooting the same load, you would probably feel less recoil.

If there’s a 2lb differential, not so much.apples to apples, and all that.