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The RCBS .243 Winchester Precision Mic is a reloading instrument built to measure chamber headspace and bullet seating depth to 0.001-inch accuracy. It reads from the datum point on the case shoulder to the base, delivering spot-on SAAMI tolerance readings for the .243 Winchester cartridge.
Operation takes only a few twists, making it straightforward to check safe, accurate loads and extend the life of your rifle brass. It is suited to precision reloaders who need consistent, reliable measurements for optimal cartridge performance.
Key Features
Brand
RCBS
Product Type
Precision Mic
Caliber
.243 Winchester
Measurement Accuracy
0.001 inch
Function
Chamber headspace and bullet seating depth measurement
Measurement Reference
Datum point on case shoulder to base
Tolerance Standard
SAAMI
Manufacturer SKU
RCBS-88305
UPC
076683883056
Condition
New
Highlights
Measures chamber headspace and bullet seating depth to 0.001-inch accuracy
Reads from the datum point on the case shoulder to the base
Provides spot-on SAAMI tolerance readings
Easy operation with just a few twists
For the .243 Winchester cartridge
How to use
Insert a fired case into the Precision Mic and turn the micrometer thimble a few twists to read headspace from the datum point on the case shoulder to the base. Use the same tool to check bullet seating depth for the .243 Winchester.
Frequently asked questions
What caliber does the RCBS .243 Winchester Precision Mic fit?
It is made for the .243 Winchester cartridge.
What does the Precision Mic measure?
It measures chamber headspace and bullet seating depth from the datum point on the case shoulder to the base.
How accurate are the readings?
Measurements are accurate to 0.001 inch and provide SAAMI tolerance readings.
