I'd be interested hearing more, as various sources of handloading data don't show 7828 getting more than about 50 fps more velocity than the 4350's.
How has temperature resistance been in your rifles? One of the reasons a lot of handloaders like H4350 is velocities are very consistent over a wide range of temperatures.
Good to hear from you JB. What you said in your first sentence is true . IMR 7828 was brought out in late 80's and I started using it with load data from the 1989 IMR manual. They listed 47.0 grs with 100 gr Ptd SPCL 47900cup at 3050 fps in a 22" bbl. A compressed charge. That load shot very well out of my 700 BDL with 100 gr SPCL's and 100gr Horn SP's. My Shooting Chrony showed an avg of 3113fps. The fired primers still had a rounded edge but got a little flatter with RP brass, the WW and Fed brass handled that just fine. A few years later I did a little trading with a guy and ended up with 4 boxes of 100 gr NPT's the older semi-spritzer style. Thinking I might need to back off on the charge going to the NPT I checked the #3 edn of the Nosler loading manual (current then) they had a 47.5 gr MAX charge listed at 3250 fps so mine ended up at 47.4 at only a 3100 fps velocity. hard to compare apples to oranges but their test gun had a 24" bbl, I was handicapped by a stock 22"er .Groups ran 1 1/8" to 1 3/8" 5 shots on a fairly regular basis, as I never try to shoot much over 325 yds with the 6x scope I was using I was good to go for the deer and antelope hunting I use it for. That original data showed me with the 7828 burn rate and pressure shown it would be pretty hard to get enough in the case to get overloaded. The same bullet with IMR 4350 was running 52000 cup at less velocity just about the same as IMR4831. My 7828 loads gave me more than the 50 fps you mentioned safely and with the accuracy desired. Fluke ? I don't know but Nosler #3 listed even more than IMR did with a bullet normally thought to increase pressure. By Nosler #4 they had gone to a full spitzer profile on the 100 gr NPT and backed off to 45.5 grs listing a 24" barrel again. I still use the older lots of powder I have on the shelf so I think the older data is still pertinent and refer to it when using it. For what it's worth about all loading data on the 243 Win took a dump about the same time the worn throat/ pressure increase deal which I'm sure you know more about than I do.
Most of my 243 use has been on antelope as I see it near perfect for that job. When the season rolls on in SD the temp extremes are from low 80's on the high end to a very rare one dipping to the 30's,very seldom hunting antelope below freezing, so I haven't worried about it much. I do like and use H4350,and other Hodgon's powder's all the time.
Hope you and the wife a great and productive fall hunting season. Magnum_Man
