What is the typical "weak link in the chain"...

From an engineering standpoint; what specifically is going wrong?

Why can't I slap a pre-assembled premium BCG into my hobby gun and call it a day??? Where else are they breaking down?

Larue is nearly 3400 and they do describe some engineering aspects:
http://www.laruetactical.com/larue-tactical-obr-optimized-battle-rifle-complete-762-rifle-18-barrel

They discuss their chamber:
XTRAXN� is a proprietary chamber feature added to reduce frictional forces caused by pressure-expanded cartridge cases bearing against chamber walls. Facilitates reliable extraction through a wide range of temperature / chamber pressure extremes. XTRAXN� extends extractor life, while having no effect on the firearm's accuracy. All this, and it dovetails well with the OBR's world-famous accuracy.

Larue has a two position gas block to make the sure-fire suppressor work right.

If the reviews posted on the Larue website are honest and not fabricated, ( I assume they are honest ) that is one amazing rifle.

Last edited by Robert_White; 07/07/14.
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