SKU: 749004650
UPC: 050806111639
The Bullet Seating Depth Gauge With Standard Guide from Sinclair International is a hand tool for handloaders who want to know exactly where their bullet meets the lands. It measures the length of a loaded round when the bullet just touches the rifling, the figure most precision shooters use as the starting point for load development and for fireforming brass. Sinclair has supplied this style of tool to competitive and varmint shooters for decades. If you reload for accuracy and need a repeatable seating depth reference, this gauge belongs on the bench alongside your calipers and dies.
The tool is machined from quarter-inch ground and polished stainless steel, so it holds up to repeated use and resists corrosion from handling. One end is turned down for 17 and 20 caliber rifles, while the opposite end serves 22 caliber and up, covering most centerfire chamberings in a single tool rather than forcing you to buy two. You insert the gauge into the chamber to establish the point at which a seated bullet contacts the rifling, then transfer that measurement to set your seating die. Used with a micrometer seating die and a comparator, it gives you a consistent baseline for adjusting jump in fine increments during testing.
Reach for this gauge when you are working up a new load, chasing the throat as a barrel wears, or fireforming cases for an improved chamber. Knowing the touch-the-lands length lets you set bullets a measured distance off the rifling and document what your rifle prefers. It pairs naturally with the rest of a precision setup, from rifle dies to a quality scale and chronograph. Browse our full case preparation selection to round out a bench built for repeatable accuracy.
It measures the overall length of a loaded round at the point where the bullet just touches the rifling. That length is the standard reference handloaders use to set seating depth and to find a starting point for load development and fireforming cases.
The tool has one end turned down for 17 and 20 caliber rifles and the other end sized for 22 caliber and larger. That two-ended design covers most centerfire chamberings with a single tool instead of requiring separate gauges for small bores.
It is machined from quarter-inch ground and polished stainless steel per manufacturer specifications. The stainless construction resists corrosion from handling and stands up to repeated use across many reloading sessions.
Yes. The gauge establishes the touch-the-lands length, and you transfer that figure with calipers or a comparator to set your seating die. Many shooters pair it with a micrometer seating die to adjust bullet jump in small, repeatable increments.
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