Shot thousands (maybe 60-70K+) of rounds reloaded for bunker practice in the 1990s using 700X. Our favorite practice load was the Win AA hull (the good early version) with W209 primer, Federal SO wad, 7/8 oz. of high antimony magnum Lawrence shot (sometimes plated), and 21.5 gns. of 700X. The only restriction for international shooting was a shot charge of 7/8 oz. or less. The SO wad was superior to any of the other off-brand equivalents for ease of reloading and patterning. They cost more but the results were dramatic.

21.5 gr with 7/8 oz? Wow!
What is the velocity? I use 17 gr with 1 oz, for my sporting clays/skeet loads which give me about 1200 fps.

We measured velocity a couple of times with a tabletop mounted Oehler chronograph and recorded it in excess of 1290 fps several times. In international trapshooting, the only restriction is the load weight (and I think they have prohibited ported barrels, thank God!!).

At our biggest shoots, a number of people would come from Spain, Portugal, Germany, New Zealand, Australia, and even Indonesia. But by far the biggest bunker fanatics were the Italians, who often imported their own ammunition for the biggest shoots. The array of loads they would bring always had outrageous velocities - one brand of shell they loved was called the Melior "Meteor". They were loaded with about 6-7% high antimony nickel plated lead shot. We chronographed several of these at or near steel shot waterfowl load velocities; some approaching 1400 fps. At 55-60 yards, a second-barrel kill out of a full choked barrel would light a target up like a fluorescent bulb.

And what would it do for your shoulder after a days shooting ? Think that's where the word " flinch " came from.

CORRECTION - I went back and retrieved the reloading logs I saved from the mid-1990s, and the bunker load referred to above was in fact 19.5 gns. of 700X, NOT 21.5 gns. My Bad!

I load with a selection of powder over here GB .the weather this time of year is cold and damp.and I get dirty barrels.When weather changes the barrels are much cleaner.I have noticed this over a number of years

Kevin, that's ok - I have a friend who use to load an outrageous amount of Green Dot for " back at the fence " trap games. His nick name was Green Dot. He one day separated the barrels on a Beretta. Told the factory he just shot factory loads and somehow they replaced them. Michael, if you're not at the high end already, you may try another grain of powder to see if they burn cleaner - just a thought.

At one point I could get all the 700x I could possibly shoot for free. I shot 1-1/8 oz loads for years and it was very clean. I then got tired of the recoil and switched to 1 oz 700x loads and it was extremely dirty despite playing with different charge levels. Switched to Clays and problem solved.

Paul I load quite a few cartridges all with the same powder load.On a nice warm day they leave nice clean barrels.But on a cold wet day the same cartridges are dirty.its the same with factory loads.Theres a artical on u tube called "George Digweed pigeonshooting with warm cartridges" At the end he's shooing with cartridges he warmed on a radiator.

I don't understand tbe concern with dirty barrels in smokeless powder. I clean the gun when i get home, regardless.