Friend Guest.....I'm back with a little data. I went through the piles of data I brought with me when I retired from the gun and ammo co's, but the only thing I found for the 20 ga. 2 1/2" was loading data using a long obsolete powder called "Super Ballistite" using 12 grs and 3/4 oz of shot. "Super Ballistite'" was a fast powder that appears to have a burn rate near Red Dot. So....that does not look like a solution.
Next, I found that Ballistic Products Inc is selling Fiocchi 20 ga Specials (2 1/2") #36520PL - 7/8 oz of #6  @ 1300 fps....$9.95 a box of 25. These are very high quality shells with high antimony shot.
The next solution.....Ballistic Products has Fiocchi 20 ga 2 1/2" , primed, new hulls for sale. These hulls have the 7mm low base wad. Now....If you roll crimp these 2 1/2" (like the originals) hulls that have the low 7mm base wad you have the same hull capacity of a regular 2 3/4" hull. This means the load data with be the same components can be used. I would suggest a load using 3/4 or 7/8 oz of shot and with Unique giving around 9,000 psi.
Best Regards, James
Lex, thanks for the info. I ordered the 2.5" Fiocchi hulls from BP about a week ago. BP is faxing me some load info for the 2.5" 20 gauge. I will aslo submit some loads on my own for testing to Tom Armbrust as I have done for my 16. I will try some Unique, Solo 1250, Univ. Clays and I. Clays powders, all in 7/8 oz. I would like to keep the pressures between 8-9000 psi. Thanks again! Kevin
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