I lighten my own carriers, but the final weight is very similar to JP's steel LMOS carriers. My 308 carriers finish out at 10.4 oz with the gas key, similar to an AR15 full auto carrier. IIRC the stock carriers were 14+ oz. I think JP's LMOS is ~10.8 oz and of course are good high quality.

I re-profiled my PSA barrel, but you can buy light 308 barrels from several companies now, Faxon is one that comes to mind. I forget the exact weight, but IIRC my 18" barrel ended up at 33 oz, and Faxon sells one that is 32 oz I think, although that may be a 16".

Definitely +1 on using an adjustable gas block. Partly because there can be a big difference in port pressure between mil 7.62 and some commercial 308; my rifle runs either one well but needs to be tuned for it, commercial 308 ends up overgassed and shoots poorly if tuned for M80 ball.

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