TargetTalk

If the gun is angled upward, then moving the table back will move the point of impact on the SCATT up. For this to not happen, the line from the center of the target and the sensor on the rifle must be parallel to the surface that the table is resting on.

minor imperfections in the level of the floor is even more likely?

Spencer wrote:minor imperfections in the level of the floor is even more likely?

Paul wrote:

Sounds to me that moving the table was changing more than just the distance. Could it also have been changing the aiming point of the rifle (and Scatt).

David, no, I'm 100% positive that only the distance was changed.

Dead thread revival. I found this discussion because I had an infuriating evening training in the hallway last night. The Scatt appeared to lose zero, but would still give reasonably consistent trace lengths etc. I changed tack and positioned the notebook screen to be in clear view from my position, then moved my position to show a 10 hold on screen. Sure enough, the sights were pointing all over the shop.

This evening I built a pile of cushions on the floor, midway between the target and the sensor, on top of a fleece blanket. As soon as I fired up the Scatt software I could see that the calibration mark was very close to the centre of the inner circle, just slightly above the middle. It used to be right on the edge of the inner circle at 1 o'clock. Sure enough, the first shot without zeroing was much closer to the inner ten ring, and once adjusted the zero stopped wandering. I had a much more productive evening.

For extra data, I have a trowel on concrete finish on the floor, covered with epoxy. The floor is uneven and highly reflective. The pillow pile fixed it perfectly.