What Anti-Walk Pin Size Should You Use?

SMALL PIN (.154 Ø)

If your AR rifle is NOT a Colt or your Colt was produced before 1991 or after 2009 it will take a SMALL PIN.


LARGE PIN (.172 Ø)

Colt is the only AR brand to produce both small and large diameter pins in their triggers. Colt AR-15 rifles produced between 1991 and late 2009 commonly take a LARGE PIN.


M&P 15-22 COMPOSITE PIN

The Smith & Wesson® M&P® 15-22 or any wider than standard receiver will use a SMALL PIN diameter but requires a longer pin length and will take an M&P 15-22 COMPOSITE PIN.


CMC Triggers offer all versions of their Drop-in AR Trigger in SMALL PIN, LARGE PIN, and M&P 15-22 COMPOSITE PIN. If you are still unsure of the pin diameter needed for your rifle you can take a measurement by pressing a pin far enough out of the receiver to measure its diameter, .172 Ø for LARGE and 154 Ø for SMALL.