09-13-2020, 08:40 PM
AA used to sell two kinds of bolts: the standard model and the "hard use." The hard use had a U-shaped notch taken out of the rear of the lug that was opposite the extractor. Theory was it would help even out the stress load on the other lugs. I believe it also used a more expensive alloy that was not necessarily stronger than the 9310 alloy used in AA's (and now the rest of the industry) bolts, but was more resistant to micro-crack formation and the resulting metal fatigue.
Bottom line: The "hard use" bolt was supposed to last for a longer round count under full auto fire before a lug broke.
Photos attached of original AA "hard use" bolt.
Bottom line: The "hard use" bolt was supposed to last for a longer round count under full auto fire before a lug broke.
Photos attached of original AA "hard use" bolt.
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:: I Drank the Water :: Revelation 21:6 ::
:: I Drank the Water :: Revelation 21:6 ::
