Headspace gauge semi and bolt same?

[scope eye]

Hi is the head spacing the same for an ar15 as a bolt in 223 it says 1.4736 on the gauge.
Dean

[nuclabuyer]

Ya if it is chambered in 223 it should be the same, but if you have a 5.56 chamber you might want to get a different gauge.

The primary difference between .223 Remington and 5.56 x 45 mm is that .223 is loaded to lower pressures and velocities compared to 5.56 mm. .223 Remington ammunition can be safely fired in a 5.56 mm chambered gun, but the reverse can be an unsafe combination. The additional pressure created by 5.56 mm ammo will frequently cause over-pressure problems such as difficult extraction, flowing brass, or popped primers, but in extreme cases, could damage or destroy the rifle. Chambers cut to .223 Remington specifications have a shorter leade (throat) area as well as slightly shorter headspace dimensions compared to 5.56 mm "military" chamber specs, which contributes to the pressure issues.