Had the buckmark rifle before, it developed a slide stop issue due to the grip not sitting quite flush with the frame, so I got rid of it. The only firearm I regretted selling. Early this month I found a brand new one local to me, haven't shot it yet.
They are nice, lightweight and nimble. Parts between the rifle and pistol are interchangeable which appeals to me.
Lesson learned with the rifle, don't use the slide stop to drop the slide, slingshot it.
Had the same problem with mine. Switched the grips for URX contour grips, filed a bit of metal on the bolt open latch and problem was solved. Zero issues now after about 2000 rounds...