The Chinese SKS‑D is the “pre-ban” version that has a standard length barrel, a bayonet lug and attached spike bayonet, and a standard stock (with a steel filler plate in front of the magazine well). Actually, there is no official rifle as an SKS‑D. Since the SKS‑D has no specific markings on the receiver, dealers coined this term in order to differentiate these rifles from the fixed magazine ones. Some people continue to use the term “SKS‑D” to refer to any SKS that uses an AK magazine.
The Chinese SKS‑M is the “post-ban” version, typically with a shortened ‘Paratrooper’ barrel and without a bayonet lug. The SKS‑M was equipped with either a thumbhole style stock or a fancy Monte Carlo style stock. These will usually have either “SKS Sporter”, “SKS M”, “SKS NR”, or “MC 5D” stamped on the side of the receiver.
It has been reported that the following variations exist:
SKS Factory modified at factory taking several different factory markings and reducing the barrel to 16 inches, and shortening the bayonet. These are the “Navy” (imported by Navy Arms) or “Type 84” rifles they have a bolt hold open of either a pin or a button detent.
SKS‑D: 20-inch barrel, standard stock, detachable bayonet, with striper clip guide, and serialized with a 4-digit or 5-digit serial number and all components are marked as well. Note that the earlier units are reported to have the 5-digit serial numbers.
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SKS‑D: 20-inch barrel, standard stock, detachable bayonet, without striper clip guide, and serial numbers starting with 88 (having 7-8 digits). Some of the components on some of the rifles are not serialized. Some “88” serial numbered rifles were caught up in customs when the 1989 ban was imposed, these were required to have the bayonet mount removed before being released to the US distributor. Note: Of course, bayonet mounts have been removed for various reasons — So just because a particular rifle doesn't have a bayonet mount, doesn't mean the rifle is one of the ones that were “caught up in customs”.
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SKS‑M: Post ban type rifles with no striper clip guide, no bayonet and equipped with either a fancy Monte Stock or one of four or five different thumbhole stocks (with either wide or narrow forearms, black painted cuts in the pistol grip or with smooth pistol grip, rear sling mount at the bottom or on the side). These have serial numbers that start with the year imported. These were imported in both 16-inch and 20-inch versions. These rifles will usually have either “SKS Sporter”, “SKS NR”, or “SKS M” stamped on the side of the receiver. However, some just marked “SKS imported by <XYZ>”. The 20-inch version is very scarce. All of the 20-inch models reported to date are marked “SKS M”, have fancy Monte stocks, and have serial numbers starting with “94”.
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MC 5D: These are assumed to have been imported without any “SKS markings” to get past the ban imposed on SKS Carbines with detachable magazines by the state of California. These are equipped with a fancy Monte Carlo stock and a magazine release that looks like it’s for a standard fixed magazine rifle. Note: some folks claim this variant is stamped with “MC 50”, but those who actually own one have confirmed it is “MC 5D”.
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A number of companies provided aftermarket conversion of fixed magazine SKS Carbines to utilize AK-47 magazines. These can typically be recognized because they continue to use the standard fixed magazine SKS Carbine magazine release.
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Added category: First conversion by Midwest Ordnance. This is the one that the Chinese came over and looked at then went back and made the 84's and then the D's. It was sold in the ATI folder stock with a filler in the mag well, 20-inch barrel, and bayonet.
