What is the effect of accuracy when shooting shorter lengt cartrages such as shooting .38 special in a .357mag, .44 special in a .44mag and .45 colt in a .454 casull? How bad does it effect accuracy?

In my case, I found that 45 Colts shot through my .454 Super Redhawk opened up my grouping quite a bit. Reduced loads in full-length .454 brass are very accurate, however. It seems that the extra .1 inch jump had a deleterious effect on accuracy, plus my chambers leaded up from the shorter cartridges.

I find using .38 sp out of my .357 accuracy is o.k.. There is a 3" drop at 10 yards.

I shoot .38 Special rounds out of my .357s for practice. There is a change in point of impact that is OK after adjusting the sights. All the best...
Gil

This is one of those things that is totally dependent upon the individual gun. I've seen .357s that would shoot .38 Special ammo just as accurately as magnum ammo, others that wouldn't shoot worth a hoot with .38, and still others that weren't so hot with magnum loads but tackdrivers with .38 special loads! Same story with .44s.