The Accuracy One Seating Depth Comparator (SDC) measures bullet seating depth, ensuring consistency. We offer an optional stand that allows mounting to a work surface for quick one handed operation. If you reload for several different cartridges, you won’t need additional adaptors. The SDC is compatible with cartridges from 22 to 30 cal with .400” and larger shoulder diameter.

In the interest of giving repeatable measurements and making the tool as universal as possible, the seats that contact the bullet and shoulder are radiused. Some other tools try to measure the bullet at the point it will contact the throat and even incorporate the 1.5 degree leade angle. This seems like a great idea, but we have found that it only results in sticky operation and dimensions that vary every time you try to take a measurement.