First Focal Plane
Also: FFP
A scope reticle that sits ahead of the erector tube. As magnification changes, the reticle scales with the image.
FFP is the standard for precision rifle work because the reticle’s hold marks read true at any magnification. Hold 1.5 mils for wind at 8x and again at 22x. Both holds are the same actual angle.
The trade-off: at low magnification, an FFP reticle can shrink small enough to be hard to see against the target. A reticle with illumination helps a lot in that situation. Most precision shooters tolerate the low-power thinness in exchange for the high-power accuracy.