Norinco nhm91 questions
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kimberkid
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Humm, I've never heard that and have owned a couple NHM-91's as well as other Norinco AK's ... And still have a MAK-90.
But to your question, you would want to check the headspace, but as long as the gas piston is the same length it shouldn't be a problem.
But to your question, you would want to check the headspace, but as long as the gas piston is the same length it shouldn't be a problem.
Reloadron
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Yeah, those bolts are made from case hardened peanut butter.
Seriously, back in the day I bought and sold hundreds of those rifles and there wasn't a thing wrong with any of them. I never heard the rumor about the bolts but have never seen anything to substantiate it. They work fine and last a long time.
Ron
briansmithwins
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You don't necessarily want hard steel in the barrel, trunnion, and bolt. As a rule of thumb, hard steels are brittle, crack, and shatter whike soft steels deform w/o cracking or breaking.
Each time you fire the barrel is going to expand as it's pressurized and the bolt and trunnion are going to deform in response to the ~50,000psi gas generated by the burning powder. If designed correctly these loads are under the yield strength of the steels used and when the load is removed the parts elasticly return to their original shapes.
The AK was designed not to need high alloy steels or other strategic materials in its manufacture. The Sov wanted to save the good steel, aluminum, and high performance materials for airplanes and ICBMs.
BSW
Each time you fire the barrel is going to expand as it's pressurized and the bolt and trunnion are going to deform in response to the ~50,000psi gas generated by the burning powder. If designed correctly these loads are under the yield strength of the steels used and when the load is removed the parts elasticly return to their original shapes.
The AK was designed not to need high alloy steels or other strategic materials in its manufacture. The Sov wanted to save the good steel, aluminum, and high performance materials for airplanes and ICBMs.
BSW
caribou
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The soft metal problems, I believe were Chinese parts kits assembled on soft recivers in California as post ban's.
The company was "B' something or another who had a different company stamp and fold their receiver untill they were shut down by the feds, as the receiver were not being made onsite.
These receiver were not heat treated at all
The company was "B' something or another who had a different company stamp and fold their receiver untill they were shut down by the feds, as the receiver were not being made onsite.
These receiver were not heat treated at all
I have two NHM-91's and put many, many thousands of rounds out of each. Both dated 94 and 12 #'s apart on the serial #'s.
The only "problem" I ever had, was shooting hollowpoint ammo. It wouldn't.
But with FMJ those things will run all day long... and then some.
The only "problem" I ever had, was shooting hollowpoint ammo. It wouldn't.
But with FMJ those things will run all day long... and then some.
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