7.62×51 / .308 Win
.308 A2-Style Buffer
5.31″ overall length
.308 A2-Style Action (Buffer) Spring
~12.5-12.75″ free length — 38-39 coils
5.56×45 / .223 Rem
“MIL-SPEC” A2-Style Buffer
5.91″ overall length
“MIL-SPEC” Action (Buffer) Spring
~12.5-12.75″ free length — 43-44 coils
