Here is a copy of the NHM 91 Semi Automatic Instruction Manual
The NHM-91 is a semi-automatic civilian development of the Russian Kalashnikov AKM and RPK infantry small arm built by Norinco of China and marketed in the U.S. by China Sports Inc. of Ontario, California (CSI Ont, CA)
Based on the Russian RPK light machine gun, the NHM features a stronger receiver and a longer, thicker-profile chrome-lined barrel measuring 20 inches (508mm) compared to the 590 mm (23.2 in) of the original RPK, along with a forward-mounted steel bipod. The NHM-91 was equipped from the factory with two 30-round magazines and a 75-round Chinese drum magazine.
Like the RPK, the NHM-91 utilizes a heavier-gauge stamped sheet metal receiver built from 1.5mm-thick stamped sheet metal instead of the 1mm thickness typical of a Soviet or European AKM. Other Chinese-made AKM rifles such as the MAK 90 and NHM 90 have thicker receivers as well, resulting in increased rigidity, heavier weight, and improved overall accuracy.
The MAK 90 rifles may have either a straight cut stamped receiver or a slant cut stamped receiver. Both were imported after the 1989 ban with thumb hole stocks.NHM 91 Semi Automatic Instruction Manual
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