I found this on what turned out to be three saddles on the non wire ABR. Took them all out rolled them on my bench and three screws were wobbly.
Someone else here said that one reason is the installer at Gibson normally whacks the bridge with a hammer to set the notch with the string because it saves time instead of filing it with the proper size file.
Another reason is that the saddles themselves might have not been drilled at ninety degrees, and therefore even a straight screw will cause wobbly travel in the bridge slots
Years ago, I bought a new ABR assembly from Gibson - bent screws. I called customer support and they sent a replacement assembly - bent screws again. I called Gibson again and talked with whoever the parts manager was...and explained situation and I just needed sadddles with holes in corrct position. He explained they get what they get...and he sent he another bridge assembly and a bunch of Gibson logo stuff as token of compensation for frustration. Between the three (3) brindge assemblies, I was able to harvet just enough saddles to make one functional unit.
They were ALL UN-NOTCHED saddles.
When I talked with the parts manager, he understood exactly what I was describing with the screwholes not consistently in the correct spot on the saddles. He concurred as well...but also stated that he has no control over the quality assurance of parts. He noted that what he gets is what he gets and those are the parts that go out for distribution.
It's really a shame to see this bridge problem going out on various guitars..including those that cost the end-purchaser many thousands upon thousands of dollars.
The bridge is a good design. It's just the loose tolerance on the saddle tooling that spoils the whole thing.
This problem could be easily fixed if someone in production really cared or was held accountable for defects.
The other problem is the entire bridge will slide on the large fat metal round plate screwed onto the posts. I think this is because the fit between the posts and the female section of the abr is horrible . The string tension is what is holding down the abr on the metal round screw on plate. Because of the poor fit this can slide all over hell and back messing up intonation