Good thread, Desertscout. I've done plenty of this at 550 using an old pallet as a target, with various 1911's, 45 Colts & 44 Mags.
I'll back your original pic as a good 500 yard photo as well as your penetration results at that distance.
“Nine-tenths of tactics are certain, and taught in books: but the irrational tenth is like the kingfisher flashing across the pool, and that is the test of generals. It can only be ensured by instinct, sharpened by thought practicing the stroke so often that at the crisis it is as natural as a reflex.” ~ T. E. Lawrence