MP 6 optical projector
Courtesy of Ronnie Freels
MP 6 Optical Projector
The process for measuring land and groove impressions with an optical projector is as follows:
- Mount the nose of a bullet on a moveable stage - the bullet image is projected onto a hooded screen that displays a measuring grid.
- Bring both edges of the selected land or groove impression into focus.
- Align one reference point on the impression with a line on the measuring grid - the reference point is designated as zero.
- Move the bullet and its mount by rotating the knob until the next reference point is reached – the width of the land or groove impression is displayed in an LED readout in thousandths of an inch.
- Rotate the bullet on its mount to the next land or groove impression.
- Repeat steps 2 – 5 until all land and groove impressions are measured.