Data for the short ten can be hard to come by especially for non-tox loads. I came across this on ShotgunWorld.com. It does not indicate if it is star or roll crimp but suspect strongly it is star. Going to a roll crimp (have to use some filler) would bring a significant decrease in pressure. You could also lower the powder charge by 10% (should bring about a + or - 10% decrease in velocity and a + or - 20% decrease in pressure)
Fed Hull, Fed 209A primer, 33.3 gr Hodgdon Longshot, SP10 wad, 1 3/8 Nice Shot, 1335 fps, 8780 psi
http://randywakeman.com/Nice_Shot_Re...a_10_Gauge.htm