NHM 91 vs MAK90 barrel

[General Ourumov]

I have a MAK90 with a ribbed barrel. I was wondering if the NHM 91 has a heavier barrel than this or if this is the heavy barrel already on my MAK90.

Are these ribs or machining marks? Full lenght of barrel? How tall are the ribs? The NHM-91 barrels are larger in diameter than the MAK-90 barrels.

[General Ourumov]

The ribs run all the way down the barrel. The ribs are all evenly placed, so I highly doubt that they are machining marks.

The ribs are machining marks left when the barrel was turned on a lathe. I have 2 MAK-90's and both have "ribs" running the full lenght of the barrel. Two machinist friends looked at my rifles and said that the marks were caused by the speed that the barrel was being turned and large amout of material removed at one time. These marks are left from making the barrel as fast as possible. A smooth finish would have required 2 cuts instead of the 1 cut used. Requireing twice the amount of time the barrel was in the lathe. Cutting production time per barrel in half caused the "ribs".

[CALIFORNIAN]

I have compared the two rifles you mentioned
and putting them next to each other and the
NHM-91 barrel has a noticable heavy barrel
appearance next to the standard MAK-90. The
MAK-90's Ive seen with the machining ribs are
probably from trying to make a lot of guns for export and not taking the time to smooth
them out they are more concerned with quantity not quality in my opinion.

[General Ourumov]

Thanks for the info. Just needed this info to know if the NHM 91 is just a long barrelled MAK or actually an RPK heavier barrell.