OAL does affect things, true. But a workable OAL of much over 1.220 and 1.250" is not possible with either of the two mentioned bullets as the bullet's bearing surfaces start to strike the rifling origin, and at that OAL the claimed velocities with 5 grains Red Dot are still very slow compared to what I get. I load mine at the mentioned overall lengths. That is, as long as possible given chambering issues.
Had the OAL's been shorter the loads would have even less excuse to be that slow. So my comments still stand. That's a seriously slow barrel.