It's splitting hairs, but this is puzzling to me. According to Berger measurements the two are similar (not the same) and 0.011" difference in bullet OAL does make a difference, correct? I think I stand corrected on this one - thank you - the bullets are nearly the same; I extrapolated this from...
It's my understanding that OTM are designed to work well in mags (bullet length, seating depth), as in tactical situations. Target are longer and can be used single-loaded, during a match, etc. The latter have slightly better ballistics.
Could you please provide measured velocities (and bullets/powders shot) that you were obtaining from all of these? I'm experimenting with a Mark V, going from 26" to 22". The important part for bullet stability is to ensure that it rotates at least twice in the barrel. So, if you have a 1:10"...