Original sentence: For rifles fitted with folding or telescoping stocks, US Federal guidelines state that measurement is made with the stock folded and/or collapsed unless the stock comes off the gun with a minimum of effort
Edited sentence: Carbine M1A1), US Federal guidelines state that measurement is made with the stock unfolded as intended for use as a rifle; exception is made for rifles with easily detachable shoulder stocks, which shall be measured with shoulder stock detached.For rifles fitted with folding or telescoping stocks (such as U