gravity-
Not always... I think one of versifier's favorite phrases on this forum is "...every weapon is different..." or words to that effect, (v-please excuse any error in that quote). It all depends on how your chamber is cut. For instance I have a .222/20 ga Savage M24 with a very long throat. I get around that by seating my bullets out as far as possible, as in just enough that they don't fall out. I am WAY over the COAL as listed in any manual, I get away with it because: a) it's a single shot, and b) it is SAFE in MY WEAPON. You ask why I don't just use a longer bullet, say a 70 grain? The twist won't support that bullet length, (mine is a 1 in 14", I wouldn't even try those longer bullets in anything slower than say 1 in 10"). Years ago, I remember reading an article on getting a .30-06 chamber re-cut with a longer throat to enable seating bullets out further. The idea was to increase the available powder capacity on the 220 grainers. So, you see there are a lot of different variables out there; the only one who can tell you what's going to work best is YOUR WEAPON. Be safe about it, start low & work up; when you get stuck on something or have any questions, post here and generally someone has already been there and will help you out. Take careSo short bullets are always going to be a pain. If I am to try different weight bullets, I need to find ones that are not hugely shorter even if lighter.
-Klaus