Generally speaking the poi difference between the loads mentioned and high velocity 240 grainers is substantial. Without further modification, am very doubtful the .160 rear site and standard front sight could be sighted in at 25 yads with 240 grainers. It barely makes it for the 180 grainers, which get 1250 fps from 4 inchers.

Am rarely shooting full bore 240 grainers, but when I do they are from a larger n-frame with much longer/heavier barrel.

However the standard sights on the 2.75 in M69 are very tough for my old eyes to use. The rear sight opening needs to be wider for thois short barrel imo.