Sig Sauer CAL-X Kit - MCX .300 Blackout - 5.5" w/ Bolt and Tapered Lug

Inter-Store Transfer
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Use this factory SIG Cal-X kit to convert your MCX to an MCX Rattler in .300 Blackout. Includes a 5.5" Blackout barrel assembly with tapered lug bolt. Compatible with standard AR15 magazines.

A new tapered bolt lug design results in smoother cycling and extends the bolt life.

All NFA rules apply to barrels less than 16" in length.