Palmetto State Armory Sabre-15 Ambi Lower Receiver

$100

Standard AR-15 lower for all five calibers. 7.62x39 steel mags can bind or fail to lock back in some magwells; an enhanced bolt catch or specific mag brand may be needed. .450 BM uses dedicated straight-wall mags that fit a standard magwell. Ambi bolt catch only.

Build with this part

Opens the builder with this part fitted. Other parts change only if they have to.

Pros and cons

Pros

Ambi bolt catch installed at the factory
7075-T6 aluminum, several Cerakote options
PSA lifetime warranty

Cons

Non-mil-spec bolt catch may need gas or buffer tuning
No ambi mag release or selector

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