OSI Gunsmithing Tools

The discovery of a citizen's right to make their own firearms in the US has led to the availability of a small number of frames and receivers on the market that are partially machined so as to not be considered restricted items, but do serve as a basis for the small scale "manufacture" of firearms.  This loose coalition of hobbyists and tinkerers refers to this as OSF (Open Source Firearms).   Like Open Source Code, there is no copyright or patent on the gun designs or parts.   Information is shared among a number of websites and books.   There are no guarantees that you will be able to complete an OSF project, but for the careful, intelligent, patient and persistent hobbyist, the rewards can be significant.  

Currently, the most popular OSF guns are based on the AR15 and 1911 platforms.  We provide certain tools used in these, but not all of the tools and none of the parts.   The up and coming designs for OSF development are based on the AKM.   We now have a functioning jig for making the main U channel bend on the AKM receiver flats sold by FAC, Joeken and others.    There is a jig/bending tool in development for correctly bending the upper lips of the receiver, but we do not have a working prototype completed yet.  

An aspect of the survival community is that many of us strive to be more independent while looking to improve our collections of guns and gear.   Invariably, survivors also do a lot of shooting and tinkering with guns and are often the first to recognize the utility of new weapons and products on the marketplace.   Where the difficulty runs in is the legal maze one must navigate just to get simple repairs on assault rifles and handgun.  What worse, many gunsmiths flat refuse to do repair work on assault rifles, leaving many survivors with broken guns and little or no availability of service.   Most of us know about as a source for tools and parts, but yet there are some tools they don't carry that we have available custom made. 


Just a quick note for the benefit of those who still have questions about the legality of home built firearms.  I have included links to a page on another site which had links to the official BATF site with information on the legal issues surrounding home built and prototype firearms built by unlicensed manufacturers.  I have also answered numerous questions regarding this in person and by email.  CLICK HERE FOR  A DIRECT LINK TO THE BATF FAQ ON THE LEGALITY OF BUILDING YOUR OWN FIREARMS.  I have also made a bigger page with more research and answers regarding legalities surrounding private manufacture of firearms (USA) CLICK HERE for more detailed legal references and information, particularly relevant to Oregon and California law.

And a special note to those law enforcement personnel and concerned citizens of Oregon who simply refuse to accept that these jigs are legal to buy, sell, own, or use, a great big FUCK YOU.   For those who lack the intelligence to comprehend the concept of clicking on a link  to find out this information, here is a quote from which is the official BATF website dealing with these issues.  

Contact information for orders and inquiries


By Phone (primary) (541) 266-8810

(secondary) (541) 556-5148

Visa, MasterCard and Discover accepted with no surcharges

A7) Does the GCA prohibit anyone from making a handgun, shotgun or rifle? [Back]
With certain exceptions a firearm may be made by a nonlicensee provided it is not for sale and the maker is not prohibited from possessing firearms.  However, a person is prohibited from making a semiautomatic assault weapon or assembling a nonsporting semiautomatic rifle or nonsporting shotgun from imported parts. In addition, the making of an NFA firearm requires a tax payment and approval by ATF. An application to make a machinegun will not be approved unless documentation is submitted showing that the firearm is being made for a federal or state agency. [18 U. S. C. 922( o), (r), (v), and 923, 27 CFR 178.39, 178.40, 178.41 and 179.105]
Translation:  It IS legal for an individual build a post ban compliant firearm from any combination of parts that could legally be assembled into a legal commercially available firearm by a manufacturer or importer.   This includes designs based on the AR15, AK, FAL, 1911 and others that are not protected by patent rights.   
AR15 Technical drawing, like a Blueprint, laser printed on 11X17 paper and laminated.  Mailed in a shipping tube by first class mail.  Discounts for quantity available $10.00

Drill bits for lower receiver.  Includes all of the drill bits you need for the trigger group, takedown pins, and trigger guard.  (four bits in all).  These are Union made in the USA of the hardest alloy in the industry.  They cut steel like HSS bits cut wood.  Can be had as a 4 bit set or five bit set. 

The five bit set shown includes the buffer tube bit listed below.  $65 separately. 

A quick note, my old supplier pulled a switch on the makers of the taps and went to Chinese made tools.  I found a new supplier which although is not using a US made tap, they do have the US made drills.   They are not the cheapest, but they are arguably among the best.   Fortunately, they are also a little cheaper than my last supplier was getting them to me for.    Rather than lower the price of the $120 upgrade drill and tap set, I am going to include more components to the tool list,  to now include a drill and tap for the pistol grip screw hole, and the long skinny 3/32" bit for the bolt catch roll pin hole.   Freight is also included in the price.  

Basic Bit kit for AR

$18 (4) (included free with jig) This price is only if you want a second set of bits with your jig, or have lost or damaged your drill bits.


Taps and Bits upgrade set

$120 - Buffer bit and tap full upgrade set.  Note, I have found a lower cost supplier for the buffer taps, so we will be including the drill and tap for making the correct dimensions on the pistol grip screw hole, and will include the 6" 3/32 bit for the bolt catch roll pin hole.  

Plate and lower finishing set, this includes a plate, alignment screws, one technical drawing and the drill bit set.   This is not a foolproof jig, in fact, it is not even all that easy to use, but it is a better layout tool than simply trying to measure everything out with no jig at all.  These are also good for use in fabricating receivers for single shot AR uppers.    currently off the market.  If you have ordered a plate kit and not gotten it, please contact 
Limited time only, 80% lowers from National Ordnance Corp, the same manufacturer that has made lowers for the Tannery Shop.  Available in heat treated Aluminum.   The Jigs are engineered specifically to work with these lowers.  They come unfinished "in the white".    (US).   Small surcharge for overseas shipping.

No FFL Required.  Exportrable.

Currently on auction at ebay


Currently out of stock


AR type drilling jigs for 80% finished lowers.   

Not for full auto conversions. 

 This is a new model now jig being produced with some upgrades that make it easier to use.  The upgrades include indexing off the magwell and a more secure bracket system for holding an unfinished lower receiver in place while drilling.  Older models of the jig included a hole for guiding the drilling of the auto sear pin hole.  This feature is no longer included on the newer jigs.   A jig may be modified to serve this function, but this will have to be done by the final user.   Pictures and instructions on the use of the new style jig will soon be available hereHere are a few more pages with information on how to use the jig and you can find discussions about the jig in the build it yourself forums of . The jig is engineered to work with the 80% finished receivers sold by the   Tannery Shop .  The new jig, like the old ones is not idiot proof, but is a lot easier to use.  If you have one of the old style jigs and wish to upgrade to the new style. you can do so at a greatly reduced cost.  Contact for details on the jig upgrade at greatly reduced cost.  You do not need to be the original owner to take advantage of the trade-up for a new style jig or super jig. 

The backorder list is moving along now and I am now open to new orders.  There are now two jigs in production.  The basic jig serves as a drilling fixture for all of the more important trigger group and buffer holes that are unfinished on the Tannery Shop lowers.   The super jig has the above features but includes a higher precision fit on the top plane and has a guide hole for the pistol grip screw hole.   The new jigs also have a threading guide for tapping the buffer tube hole.   

The jigs come in a kit with the four drill bits shown above (and the price is included in the kit).  The kit also includes a  technical drawing of an AR15 receiver.  You will still need a small number of common hardware store bits and taps to finish a lower.   There are also some specialized drills and taps needed, specifically a 1-1/8" drill and 1 3/16X16 X 16 plug tap for the buffer hole.   You can save the hassle of finding these locally by ordering the upgrade drill and tap set for an additional $120.    The upgrade drill and tap set also includes a drill and tap for the pistol grip screw hole, and a long 3/32" bit for the bolt catch roll pin hole.  

Information on gunsmithing ARs

BATF regulation on building your own firearms

Forums on gunsmithing ARs -, Roder Custom

A new source for lowers which will probably be compatible with the jigs is Note that while we have tested the Tannery Shop lowers, the Sgt Freedom lowers have not yet been tested with the jigs.  My observation of the website also indicates that they may require more work than the Tannery shop lowers.   You can see a partial evaluation on the Sgt Freedom lowers HERE

Click here to see the progress of the AR project - Clearwater Forge

We have resumed production of the jigs and are now open to new orders.   New orders are being shipped within two to four weeks.   Export jigs are currently in stock for immediate shipment.  

 If you ordered a jig prior to Feb 1 and have not gotten it, please contact me  at 


Super Jig Kit For AR

$275 "Super" - includes provisions for the pistol grip screw hole and tighter tolerances for pre-fitting the top plane to spec.   This is the most popular model.


Export Jig kit for AR

$310 -"Export" - an improved and beefed up version of the super jig.  The Export model is set up for drilling from both sides.  This enhances the longevity and service life of the jig to reduce the need for periodic rebuilds which require sending the jig back for replacement of the side and back plates.   This is the model sold to NOC and most overseas buyers.   

Shipping within the US included in the price.

Paypal surcharges for credit card use are waived on this item.  

Note that these are made on a semi-custom basis from a contracted fabrication shop that is primarily geared toward other business.  The production of these jigs revolves around other production schedules at that shop and there can be delays that are out of our control, although timing on this is usually consistent with wait lists for the rental jigs and it still works out a lot cheaper than the production figures I have been quoted with precision tool manufacturers that have shop rates above $90 per hour.   Payment in advance is normal for this sort of production work and constitutes an agreement to purchase.  Order cancellations will have a 20% fee if they are done more than two days from receipt of the money.   There will be no refunds on jigs that have been shipped, but defective jigs will be repaired or replaced.   Damaged and or worn jigs can be repaired for a nominal fee.  This includes replacing the back plate, side plates, or relining any stripped or warbled out holes.   Owners of older style OSI jigs (the ones with the auto sear hole) can have them replaced with a newer style jig at nominal cost, but the older jig must be returned or destroyed.

The AR jigs can be rebuilt for an average cost of $80 each.  This cost includes return shipping.   Rebuild of export or builder squad specification jigs is more.  

Drill bit for AR15 buffer tube tap.  This is a 1-1/8" hard alloy drill bit for pre drilling the hole in the back of an unfinished AR15 receiver in preparation for tapping it for a buffer tube.   Bits and reamers in this size normally cost a lot more money, but I was able to custom order some from an industrial supplier and get a volume price.  If you find a lower price on this type of drill bit, let me know.   Designed for use with the drilling jig above, but will work with the jigs from Tannery Shop and AFretired from   $65 Each, or get the package deal listed above.  Shipping included.


Buffer Drill bit for AR


Buffer Tap for AR

1911 Jig for frame rails

See the links below for details.    

NEW, the final OSI jig prototype in action. 

Other links for building your own 1911



Payment in advance is normal for this sort of production work and constitutes an agreement to purchase.  Order cancellations will have a 20% fee if they are done more than two days from receipt of the money.   There will be no refunds on jigs that have been shipped, but defective jigs will be repaired or replaced.   Damaged and or worn jigs can be repaired for a nominal fee.  

These are built in small production batches and almost always ship within 30 days of the order, usually within two weeks of payment.   Please note, this is a general time estimate, emailing twice a day and threatening to reverse charges does not make the production shop or shipping trucks move any faster.  

Kit includes jig, slitting saw, saw arbor, and specialized slide fitting file.  

$142 shipped in the US.   

1911 Jig kit
AK Flat Bending Jig

NEW,  We finally came up with a working model of a jig for bending the unfinished AK receiver flats available from a few places on the net.   This is the most expensive and difficult tool we have made for what should be a dirt simple task, but the end product is something that even a drunken Siberian Peasant could use to get the main bend on an AK receiver flat to turn out right every time.  

Payment in advance is normal for this sort of production work and constitutes an agreement to purchase.  Order cancellations will have a 20% fee if they are done more than two days from receipt of the money.   There will be no refunds on jigs that have been shipped, but defective jigs will be repaired or replaced.   

We tried several less involved designs to come up with a cheaper jig, but they just would not work reliably, and even at half the price of this jig, a $250 jig that does not work all of the time would probably just piss people off and we could not sell any after word got around about it.   While these jigs are not cost effective for one or two project guns, realize that the fact that they will last indefinitely plays a major role in the economy of scale on the service life of the tool.    Also consider the many variations of AK parts kits available and how you could easily build up a collection of ten guns with none of them exactly the same and none of them costing over $350 to build.    Even the most deluxe high end AK parts kits only cost about the same as a lower grade AR15 parts set minus the lower receiver.   

If you think that bending your own flat is simply not going to be practical, you do still have the option of using one of the excellent receiver channels from   They come in the right general dimensions and are already heat treated.   While the work can be tedious, very few specialized tools are required to finish one of these into a working gun.   The 4130 alloy they use is very weldable with even the cheaper flux core welders and can be used to make substitute sections for welding into receivers that have been "demilled".   

There is no backorder on this item.   These are built in small production batches and almost always ship within 30 days of the order, usually within two weeks of payment.    

Click HERE for more information about the new AK jig.  

$500 shipped for the kit.   

AK Bending Jig Kit

We will have a real bending jig for the top rails and a barrel press available in the future but for now, we have a working jig that takes care of the hardest part of bending the Hesse/Joeken/Vulcan/FAC/Tannery receiver flats without mangling the magwell area of the finished product. 

Until the top rail bending jig is perfected, we reccomend you use a standard heavy duty compact sheet metal bending brake for the top rails of the receiver flats.    Bend the top rails BEFORE using the bending jig for the main center bends.

We are not doing any rentals on these bending jigs, but if you buy one and are finished with it, you will find the situation fairly easy to recover your money back if you put the jig up for sale on one of the major gunsmithing forums. 


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