Full length sizing a straight wall case gives you a Coke bottle effect. )( The longer the case, the more visible it is to the eye. Years ago I was told this was due to spring-back and the softening from annealing in the brass manufacturing process. The guy who explained it to me was an old timer gun smith and being a dumb kid in his 20s, I wasn't smart enough to pay attention and learn all I could have from him. The things I have taken away from our visits back then have lasted to this day.
He told me that my straight wall brass that was full length sized would crack lengthwise in about 5 firings. He was right on. 357, 38, and even 9mm all did that. I learned to size only enough to hold the bullet and now rarely get the full length cracking. Some cracking at the mouth from work hardening in the crimp area still show up. He also told me to keep my reloads separated for each gun. Firing brass in the same gun, and limiting the sizing to chamber fit and bullet hold, would extend the life of the brass for reloading. Again very accurate information.
Some other things I remember from him: G96 gun cleaner/lubricator is great stuff. I still buy it when I can find it. Almost has the after-shave appeal as Hoppe's #9. Two gas seals in the recess on the Remington Model 1100 work better than 1, and will last longer. Both of my 1100s have two gas seals. One last note for today, 2 3/4" shot shells will shoot just as fast and just as far as 3" shells. They just have less shot and take less powder to do it. If you are aiming in the right place when the shot goes off, the pattern will be there. My best 60 yard goose loads were loaded in Win AA hulls. That was back in the day before required steel shot and when 3" shells cost $2-3 a box more than 2 3/4". These loads work great on turkeys too...
Have a good weekend.