Originally Posted by 75Vette

Good eye Matt. That was a transitional time for the 629-3 & 4, & 29-5 & 6. I believe the full underlug Classics were the first to get the rounded rear sight and drilled & tapped top strap. The 629-4 & 29-6 had it on all models. Whatever the case, that rear on the OPs gun is protruding too far. Trampis, just for giggles I'd pull that sight and see what's underneath it.