CA-Legal AR-15 Stock Adapter

Measurements and Sizing

Supported Receivers

The Hammerhead is designed to fit mil-spec AR-15 receivers. We've test-fit it with many brands of forged lower receivers.

Overall Length

Overall length of a typical Type I Configuration as shown, with YHM muzzle brake, 16" barrel, and ACE ARFX-E stock, is 36" from tip of muzzle brake to back of buttpad. 32" from tip of muzzle to back of pistol buffer tube.

Distances to Trigger and Mag Release

Add 5.9 inches to your buttstock length to figure LOP.

Measurement of Finger Length

Lay your trigger hand flat on a table or other smooth surface. Press the end of a ruler firmly into the web of your hand. Measure the length of the trigger finger and thumb. Compare these measurements to the dimensions above to get a rough idea if the Hammerhead will fit your hand.