Accuracy Testing Question

Doing some 1911 accuracy testing. I loaded up some softer rounds that I plan for the short line w/iron sights, but I'd like to test them off of a bench at 25 yards with a rail/dot and rest. I know they won't cycle properly with the additional weight, however, does inherent accuracy with a specific load degrade when you add or subtract slide weight? The gun locks tight so I figure the bullet is gone in short time and slide weight does not matter? Thanks...

I found an old grip mount and an Ultradot for doing what you are wanting to do.

There is a potential for vertical stringing due to early unlock with too light of a spring but you are going the other way so I think you are probably ok. I would worry about how it performs in your hand with recoil so it's a good idea to simulate as close to final configuration as possible. Of course there's lots of variables there with grip, but we can only get so close to perfection.