1989 Ban Overview:
In 1989 various semiautomatic rifles were determined by ATF to be “non-sporting” based on a variety of features and banned from importation. Shortly after, Congress restricted the modification of legally imported firearms, when those modifications result in a firearm that resembles one of the restricted ones. Note that these restrictions apply only to imported firearms. In addition, C&R firearms are exempt these restrictions.
Though these rules seem to be in an almost constant state of flux, some generalizations can be made.
If you are not prepared to understand the legal minutia associated with various firearms laws, leave your SKS Carbine alone—Don’t modify it or purchase one that has been modified by someone else.
If you’re willing to understand only a little legal minutia, see the info on the info on 10 imported parts.
What is the history of this ban?
On July 6, 1989 various military style semiautomatic rifles were determined by ATF to be “non-sporting” based on a variety of features and banned from importation. The authority to impose this ban stemmed from the 1968 Gun Control Act, specifically Title 18 USC § 925(d)(3). This ban included the “SKS style rifle” with certain features.
Shortly thereafter, various manufacturers began importing foreign parts and assembling them on locally made receivers. Congress responded in 1990 by passing new regulations. Title 18 USC § 922(r) made it illegal to build any firearm prohibited from importation as “non-sporting” under Title 18 USC § 925(d)(3). Note that only assembly is illegal—possession, transfer, etc, of such a firearm are not covered.
However, the 1990 law was so vague that in 1993 the ATF wrote regulations (178.39) that spell out the “10-or-less imported parts rule” and what “imported parts” mean. It states that only 10 imported parts are allowed in an unsporting imported firearm. This new law and regulation shows up in the 1995 Federal Firearms Guide. During the interim many rifles were built at home from imported parts without concern to parts count.
Finally on April 6, 1998, another study on what constitutes “non-sporting” firearms “result in a finding that the ability to accept a detachable large capacity magazine originally designed and produced for a military assault weapon should be added to the list of disqualifying military configuration features identified in 1989.”
Bottom Line: If you wish to modify your imported SKS Carbine, you will need to understand what is and is not allowed. Otherwise, it is very likely that you will inadvertently violate Federal firearms law.
Just what happened on July 6, 1989?
For the full story you have to go to the 2005 Federal Firearms Regulations Reference Guide. However, on that date the Secretary of the Treasury used the authority delegated to him by Congress under Title 18 USC § 925(d)(3) to restricted the import of “non-sporting” firearms.
Just what features would restrict an SKS Carbine from import since 1989 is not clear. However, the ATF web site contains a link to the 1998 Study Determination, list of eight military features that could cause a semiautomatic rifle to be classified as “non-sporting” (prohibited from importation in ATF terms):
1. Ability to accept a large capacity magazine [see explanation of “detachable large capacity magazines”]
2. Folding/telescoping stocks
3. Separate pistol grips [see explanation of pistol grips and thumbhole stocks]
4. Ability to accept a bayonet (bayonet mount) [see explanation of bayonets.]
5. Flash suppressors
6. Bipods [see explanation of bipods]
7. Grenade launchers
8. Night sights
This is not to say that a particular rifle having one or more of the listed features should necessarily be classified as “non-sporting”. Indeed, many traditional sporting firearms are semiautomatic or have detachable magazines. Thus, ATF has stated that these criteria must be viewed in total to determine whether the overall configuration places the rifle fairly within the semiautomatic assault rifle category.
Because this “restricted feature” list is not found in either law or regulation, the features that could restrict an SKS Carbine from import are not fixed. ATF could decide to allow certain features on particular configuration, while prohibiting them on others. The only way to know if a particular configuration is legal for importation is to ask. Don’t be shy! ATF has said that they will provide a “determination” to anyone who requests one. If there is any doubt, you should write ATF.
For additional information you can study the Full text of the ATF's 1989 Report or the full text of the ATF's 1998 report.
Remember that Title 18 USC § 922(r) made it illegal to build any firearm prohibited from importation under Title 18 USC § 925(d)(3). This includes modifying your imported SKS Carbine to be “identical” to one that is prohibited.
What features would restrict an SKS Carbine from importation?
Just exactly what features would restrict an SKS Carbine from import is unclear. For example, a copy of a 1998 ATF Brochure from the Simonov.Net web site (253kb) “includes” SKS Carbines with any of the following three features:
· Folding Stock
· Folding Bayonet
· Detachable Magazine
Therefore, it seems very clear that adding one of these three features to an SKS Carbine is definitely restricted. Unfortunately, the word “includes” opens the door to the possibility that additional configurations are prohibited. The ATF’s 1998 Study Determination, contains the more expansive list of eight military features that could prohibit semiautomatic rifles from importation. Based on info from ATF to members of the Survivor's SKS Boards web site, the following features should also be considered as restricted:
· Flash suppressor and/or threaded muzzle. ATF has given conflicting signals on these, but current ATF information is that threaded muzzles are a restricted feature. For the latest info see the SKS Boards discussion on muzzle threads (which is in conflict with an older ATF letter posted on William Bardwel's site). For more information on covering muzzle threads, see the discussion on removing the grenade launcher from Yugoslavian M59/66 rifles in this FAQ
· Grenade Launcher.
· Telescoping stock.
from
http://www.victorinc.com/SKS-FAQ.html#_Toc98250432 
