The RCBS Precision Mic for .270 WSM (RCBS part no. 88315) tells handloaders their chamber headspace and bullet seating depth to within 0.001 inch after just a few twists. It measures from the datum point on the case shoulder to the case base, which gives readings against ANSI/SAAMI tolerances rather than a guess. RCBS sells a Precision Mic for each cartridge, and this one is made for the .270 Winchester Short Magnum. The readings help you load safe, accurate rounds and get more life out of your brass and your rifle. If you chase consistent seating depth and a correctly set-up sizing die, this is the tool that shows you where you stand.

Key Specifications

• It is made for the .270 Winchester Short Magnum (WSM), so the gauge fits that case and no other cartridge.
• It measures chamber headspace to within 0.001 inch, which shows how your sized brass fits the chamber.
• It measures bullet seating depth to within 0.001 inch, so you can repeat a seating depth load after load.
• Readings run from the datum point on the case shoulder to the case base, the reference that headspace is judged from.
• It gives ANSI/SAAMI tolerance readings, a standard you can check your brass against.
• Operation takes a few twists of the gauge, so checking a case is quick enough to do throughout a loading session.

Frequently Asked Questions

What does the RCBS Precision Mic measure? It measures chamber headspace and bullet seating depth to within 0.001 inch, reading from the datum point on the case shoulder to the case base.

Which cartridge is this Precision Mic for? This one is for the .270 Winchester Short Magnum (WSM). RCBS makes a separate Precision Mic for each cartridge.

Why would a handloader use it? RCBS calls it an indispensable tool for safe, accurate loads that extend the life of your brass and rifle.

Buy the RCBS Precision Mic, .270 WSM

A good load starts with knowing your numbers, and the Precision Mic puts headspace and seating depth in front of you in thousandths of an inch. See more tools in our gunsmithing tools and order from our Lubbock, Texas gun shop for fast, insured shipping.