I just bought 1500 Gold Dot HP's 9MM 147GR bullets. I am using the Speer #14 Reloading Book (2008). Bullets mike out at .355 as listed in book. I am using Unique powder in the middle of the recommended charge. I always start with 10 loaded bullets when working with a new bullet or powder. This is my first time with 147GR bullets. The problem is after seating the bullet, there is a bulge in the case at the bottom of the bullet. The case will then not chamber check as it sticks at the bulge. Out of 10 bullets only 2 will chamber check and they have a very slight bulge. The bulge is only on about half the diameter of the case almost like the bullet was getting seated not quite in a vertical manner so it would have equal pressure on the whole case. Bullet is being seated to 1.13". The seating die has just been cleaned so there is no gunk in it. Cases are all once fired, cleaned and tumbled. Loader is Dillon SDB. I have tried to move the flaring die down a little to see if that would help but no go. I am not new to reloading, but this is a real stumper. Any help would be appreciated.