I found the REX powder data from Grafs to be a bit conservative. I couldn't get anywhere near what they were suggesting in thier data with any of the 3 rex numbers I have. I've used REX 1,2,and 3. Mostly I use REX 1 for trap and sporting clays loads. I bumped up the powder charge untill I hit the 1200 fps velocity over my chronograph and have had no problem whatsoever with them. I've been very happy with REX powder in general, but a bit dissapointed that the data is off so far. I had loads that should have been going 1200' that were hard pressed to shoot 1000'. Call me insane if you must, but I do load them a tad over what the Grafs data says and have very good results. I found that with my Gold Medal hulls, and I don't have very many, just a few hundered, I need to use the Federal wannabe by Claybuster. SO3 or something or other. It is a bit longer and sems to be a bit stiffer allowing for a much nicer crimp than when I used the AAs, Claybuster AA wannabes, or Figure 8s or the windjammer wads. They all left too much space between the shot column and the top of the hull to get nice firm/flat crimps. I used the Federal style wad and that got better imediatly. Learning how to adjust shotgun shell loaders for good crimps and using different wads and hulls can be a bit trying to say the least! I'm getting better at it though. I've been wanting to give the new style Gold Medals a try, but I've not found anyplace localy that stocks Federal high end shells. I'm not about to pay the rip-off prices plus shipping and buy them on e-bay. Can't believe what some folks will spend for once fired hulls, especially considering you can get STS and AAs for under a 5 spot per box brand new and ready to shoot. Good luck with your loads, I experiment a lot with different hulls, wads, powder, and primers with my shotgun shells. If you look long enough sooner or later you will find someone who has a "published" load for just about any combination you can reasonably come up with.
BP