For an AR-10 chambered in .308/7.62 with a collapsible stock, if it has an AR-10/A5 length carbine buffer tube (which is 7 ¾” long on the inside) then it needs a 3.25” buffer and we recommend the KynSHOT AR10 3.25” carbine hydraulic buffer (Part# RB5005) and an AR-10 carbine buffer spring, either the JP 308 carbine buffer spring (part# JPS-OSC-308) or the SPRINCO AR-10 carbine buffer spring (color code ORANGE - Part# SPRINCO-25762). If your rifle came with a 3.25" buffer and you have not changed your buffer tube, then this is what you need.
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