PF-040 (Pins, Forward Controls, 0.040) is a set of elegantly simple, and superbly crafted AR15/M16 pivot and take down pins. Machined from 17-4 PH SS bar stock and QPQ finished, these pins are 0.040 longer than TDP spec pivot and take down pins.
PF-040 pins can be aptly described as “reverse extended”, in that they’re longer on the left side of the receiver, the additional length of the take down pin doesn’t interfere with ambidextrous safety operation. When PF-040 pins are pushed in from the left side, the +0.040 transforms to extra length and grasping area on the right side pin head, which combined with their silky smoothness, makes pulling the pin a cinch.
PF-040 has the same elegant and unadorned pin heads design that is in line with our design philosophy which prioritizes functionality over aesthetics. PF-040 right side pin heads (when installed on a receiver, with the muzzle pointing away) are flat, with a small 45 degree chamfer. Serrations or dimples on the right pin head would be useless, so they’re completely plain. There is a small dimple on the other side of the pin head, the tip of bullets (up to 9mm) can be used to push the pins in on tight fitting receivers.
PF-040 can be purchased with the optional takedown/pivot detents (4) and springs (3) kit. The odd numbers of included components probably deserve some explanation. Even for experienced AR builders, it’s not uncommon to launch the pivot pin detent into the twilight zone. It’s also fairly easy to bend the take down pin detent spring during installation of the end plate and castle nut.