No Sir, tha case trim length has nothing to do with Cartidge OAL. That is simply according to the die set up and the press. When you say .010" to .015" do you mean total or do you mean .015" plus or minus where you could have a total of .030" from shortest to longest? .010" total is not bad in a handgun. .030" is somewhat excessive in my book.
Things to look for:
Are you setting your dies at the place where the handle on your press is at a Mechanical stop?
Does the seater stem in your die have a flat nose or a cup? I have seen cupped stems seat all the bullet ogive diameters the same, but the bullets have a little variation between the ogive and the point.
Is there wax build up in your seating die from loading cast bullets?
Is your case holder too tight to allow the base of the brass to rest flat on the bottom? I have seen tight shell holders hold the brass up by the groove, not letting the base sit flat, throwing off OAL.
Leo: To clarify, my OALs in my current batch of hollow points range from 1.140" to 1.155".