Mid twenties of Red Dot would be a very safe starting point. If heavy shot loads or high velocity are desired, a slower powder than Red Dot would be called for to keep pressures under control. The 12 gauge data you mention starting at 18.X grains is with good sealing plastic wads, not paper wads. William Davis is correct. 12 gauge data is usually, maybe always, safe in a ten gauge, but we're talking paper wad data from the sixties. Modern 12 gauge data is lighter than it needs to be if we're loading it in ten gauge cases. Red Dot data for 1200 fps loads in the paper wad era was 23 grains, gravitating to less than 19 grains today.

If you check my spreadsheet you will see that is from published load data printed in the 1960's by Hercules Powder Company. If you look at my notes I cautioned that Red Dot powder may have had a change in formulation and I would start by reducing them by 25% if using in composite barrel guns.

The fiber wad has some advantages vs card wads as fillers. Buy 16 g fibers too big and split with a knife to suit. Often the split is half & you get two wads out of one. They also have some “spring” that helps obtain correct stack height .

Card wads most useful over shot were they can help with poor crimps in well worn Cheddites hulls. Otherwise Cheddite is a limited load # hull.

William

I don't load Red Rot or WSF but I do load Unique in my Short-10. You can use nitro cards and fiber wads in the same loads as an SP-10 or other 10g plastic wads but you will need to play around with the size of your wad column to make sure your crimps will be good.

I'm in the process of loading 10's as we speak .

I've loaded a bunch with 1 1/8 ounces and a powder puff load of Red Dot . I've also loaded a bunch with 1 1/4 ounces and SR7625 again a not what I would call hot load .

But I'd forgotten you gave me the data for your Unique load . I have it saved so I just might load up a box of them to try at Tuesday night skeet :whistle:

Just loaded a box using Unique and an ounce and a quarter of #8’s per Sir Koneski’s details . Although I was able to get by with one 1/8” 16 gauge nitro was in the cup and my usual over shot card to make the crimp flat . I’ll try these Tuesday evening at skeet and a few of my SR7625 to see if perceived recoil is close .

I almost forgot I’ve got a 10 gauge 2 7/8” load at home scribbled down from a friend using Universal Clays and 1 1/4 or 1 3/8 ounces of shot . That’s his Southern SxS load . May have to load a dozen or so of them tomorrow just for the heck of it .

Craig, you sure those 1 1/4 or 1 3/8oz loads aren't too light for clay birds ? Man, my shoulder hurts just thinking about them. I like 1oz loads in the short 10 for clay bird games. If my 12ga 3/4 or 7/8oz loads work just fine in a 12ga there's no reason a 1oz load won't work in a 12 or the 10. 20grs of RD, GD, or Promo all work. 17grs of 700x is also fine in the 10 with fiber wads and 1oz of shot. JMHO

The 1 1/4 7625 and Unique loads aren’t bad . Shot the 7625 loads at sporting clays last Friday and shot a mid 80’s score . The Tuesday before the Unique loads worked nicely at skeet even though I mostly shot backwards doubles at all stations . My 1 1/8 ounce Red Dot loads worked well for a friend last Friday at sporting as well . Sorry to say I’ve not tried any of the 1 1/4 with Universal Clays yet as I’ve misplaced the paper I had the load scribbled on .

Did you ever work up a 10 gauge load with fiber wads?