This could be in a couple topics but here goes. I PM'd Lee Wiggins about this but I'd like the opinion of the group. I also plan to test this.
John Ardito made cases for his .308x1.5" rifles with an inside shoulder in the case neck. This served as a seating depth stop that would withstand the force of seating the bullet into the lands and a tight throat fit. It also allowed bullets to be finger seated at the bench. Some thought this was cheating when it comes to the rule of fixed ammo since the bullet was seated loosely and only to little more than the gc area. I have done this with some success, but not good consistency. Would neck sizing and increasing the neck tension help? I plan on testing this along with finding out which seating depth is best. Moving the bullet into the tapered throat 1/8"after it first touches is difficult. Lot's to try here, but I'd like your opinion especially if you have info on how John Ardito did it or anyone else that has tried this.