I have an early Colt Delta Elite 10mm that was accurized by Alex Hamilton (10 Ring Precision) in the late 80s.  It was always an accurate pistol, but has been a safe queen for the last 20 years or so.  I wasn't sure what springs were in the gun, so I fitted an EGW square (small radius) firing pin stop, 23 Lb Mainspring and a 22 Lb slide spring.  Also added an extra power firing pin spring.

When I took it to the range, the POI was 3" to 4" high at 25 yards with the rear sight bottomed out.

Could the cumulative effect of the above changed the lock up enough to change the point of impact?

Any thoughts?

Thanks,

Paul

No one else seems willing to pick this one up.  I have been out of it a while working on various projects that keep me away from the interwebs.

I will offer some comments.

None of the changes you mention should really change POI at all.  The data I have read indicates that none of these are going to have a significant impact on timing, which is controlled in the 1911 by the link.

Best course of action would be to swap in the original parts and repeat the test with the same ammo.

I agree with what has been said above... nothing "should" change your POI out of the changes you listed.  Its more likely that you are getting a different recoil "feel" and are flinching in a different direction.  One way to tell would be to swap back in the stock parts and test again... or, have someone else who you KNOW is a good shot, test the POI (without first telling them what to expect... make it a surprise).

Good luck!