OK, before somebody causes grief on me THE TITLE IS SUPPOSED TO BE 9MM NOT 0MM. I reread my post several times to make sure it was as correct I as I could make it but never looked at the title until it was too late. Naturally, one cannot edit the title.
I use a 126 TCBB grain bullet from SAECO molds that is very similar to the LEE #90239 in profile. I have shot 1000s of these over the years using 700X. For reasons not germane to this issue I want to try Blue Dot.
My 700X load ended up with an OAL of 1.070" so the case could crimp into, more or less, the middle of the upper driving band, in other words the full diameter of the bullet between the start of the ogive and the lube groove. It seems the accepted OAL with just about any bullet is 1.120"-1.150" depending on profile.
Never felt there was any problem. However, today I loaded some with BD starting at 6.4 and going to 7.0 in .2 grain increments. Alliant says one can go to 8 grains but I would like to know how because even with my loads the case is VERY full, so full as to be a compressed load if I seat the bullet as I have described above. Given the compressed load aspect, I'm concerned that I am creating a situation similar to having the bullet shift back into the case and having an excessive pressure issue.
If I seat the bullet out far enough to be at the recommended OAL I would be crimping in the lube groove.
So, am I just being paranoid or will I be OK. Just going out and test firing is probably an option but I really DON'T want to be replacing a blown up gun. I need the slower burn rate of the BD for this application so I suppose I could get a different mold but I sure don't want to if I don't have to.
I have been loading 9mm for several different brands of guns using this bullet for over 30 years and thought I had a pretty good handle on this reloading thing but I seems I am able to find a way to complicate my life no matter what. Oh well.