I typically reload for my 270win & 30.06. Bullet depth / seating and COL is governed by the rifles chamber length. My 270 likes .015 set back & my '06 likes .025 set back. This is where several months of trial & tribulation have led me. Accuracy & consistancy are best here.
I notice on some bullets (like Nosler Custom Comp.) when I seat the bullet a usual, I can see the bump on the neck showing where the end or bottom of the bullet is. Now, Is there any advantage or disadvantage to seating bullets to a depth where the end of the bullet is even with the bottom of the neck?. For example, where the neck & shoulder meet, If I seat a bullet where the bottom is even with the end of the neck, would it cause any hinderance or help?
Somehow, I sorta suspect most of the responses will be "you'll never know unless you try it".
I seem to recall an article I read a few years ago where some competitors refused to use certain bullets due to the length. Meaning, the end or bottom of the bullet protruded past the end of the neck & extended into the case by some small amount. I recall it mentioning the additional length would cause extreme inconsistancies with the accuracy.
Does anyone have any experience with seating bullets with the bullet bottom even with the case neck bottom to where it does not extend into the case or end short in the neck? Or, is it a situation where best results are obtained from finding the sweet spot with the bullet set back or jammed into the lands?
What say ye experts? Help put an old guys worries aside... ??? ??? ???

P.S. I have a few bullets that are kinda long where they extend into the case even when they're set tight with little or no jump. Those seem to be the least accurate and are somewhat inconsistant. They're called "Blems" from Midway & look like Hornady SST 150 gr. x .277".