I’m at just under 4 lbs with optic and no poly parts, well, other than the grip. Coulda saved weight with aluminum take down pins too but wanted to use more durable titanium. Also didn’t want a polymer upper or lower either. I wanted all alloy, durable, reliable gun.Ordered an NFA poly LPK. They haven't been in stock for a while, and were only $35. The poly LPK will save just under 3oz.
Also found this Aluminum bolt carrier that would cut about 5.7oz, for $160.
https://www.rainierarms.com/shooting-innovations-ar-15-lmb-low-mass-bcg-gray/
That got me curious. So I made an Excel chart to see how light one could go using some poly parts. Sub 3.5lbs is possible. Wow!
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