sr90,
The pressure ring I was refering isn't a driving band or something like that like you typically see in military sabot rounds and such. But most shooters who refer to a pressure ring on a standard jacketed bullet is refering to the junction of the boatail and the body of the bullet and that was my intention. Sorry for that confusion.
That .030" deeper you would have to seat them isn't bad. So I would say yes it would be realistic. Just make sure your gunsmith is aware of this situation so he can get the throat depth properly set. If you go much deeper your taking away from case volume, possibly raising pressures and/or lowering potential velocity.
As an example of how much bullets seated into the case make...
In my 6.5-300 WWH when Sierra came out with the 155gr MK in the early '90s I tried some in my rifle that was throated for 140gr MKs. I forget how deep they went into the case but it was more than .030". Seems it was more like .100" or more. Well the best velocity I could get out of that combo was around 3050fps when I ran into pressure signs. I also own a 6.5-300 Winchester which has less case capacity than the 6.5-300 WWH case, but it was specifically throated for 155gr bullets and I could get 3200fps with that combo even with the less case capacity. Granted different barrels and such made some different I'm sure, but to get 3400-3500fps from 140gr bullets in my 6.5-300WWH down to 3050fps when the bullet only weights 15gr heavier didn't sound right to me.
hope this helps,
Steve