Frequently Asked Questions
Frequently Asked Questions
- Is there a spec sheet for your optic mounts that shows length, material, etc.?
- The optic mount I received is too short for my rifle.
- Can you explain in detail why my exciting new XYZ brand AK lower handguard won’t fit with your AK optic mount?
- How come your M6 mounts won’t fit Universal (or Plainfield, Iver Johnson, etc.) commercially made Carbines from circa the 1960s and ‘70s? I mean, my uncle carried one in Korea, and…
- What about my Saiga AK? Do you make a mount for it?
- What about my Palmetto State Armory AKM?
- Is there a spec sheet for your optic mounts that shows length, material, etc.?
- The optic mount I received is too short for my rifle.
- Can you explain in detail why my exciting new XYZ brand AK lower handguard won’t fit with your AK optic mount?
- How come your M6 mounts won’t fit Universal (or Plainfield, Iver Johnson, etc.) commercially made Carbines from circa the 1960s and ‘70s? I mean, my uncle carried one in Korea, and…
- What about my Saiga AK? Do you make a mount for it?
- What about my Palmetto State Armory AKM?
Q: Is there a spec sheet for your optic mounts that shows length, material, etc.?
A: Indeed, there is. Click the buttons below to view or download a PDF file that lists the length, slot count, weight, and materials of every mount in our store.
Q: The optic mount I received is too short for my rifle.
A: If you ordered the mount that was recommended for your particular firearm, then the mount is most likely not too short. As the instructions sent in your package explain, the UltiMAK optic mount is slightly shorter than the original gas piston tube – and this is an intentional design feature. The following video explains this design choice in greater detail and provides a visual demonstration as well:
Q: Can you explain in detail why my exciting new XYZ brand AK lower handguard won’t fit with your AK optic mount?
A: Ask them. We didn’t make the thing. First off, it should be known that we designed our AK optic mounts to fit with virtually all original (military) AKM handguards – in wood (other than Chinese wood), Bakelite, polymer, or polymer and steel – which were standard at the time of the design process. Any other handguard will therefore be a “wild card” when it comes to installing an UltiMAK AK optic mount. In other words, any aftermarket AK lower handguard is a “wild card”. That means that if the designer did not specifically make sure that his design was UltiMAK compatible, or did not use the original AKM pattern internal dimensions, it might not fit without alteration.
Magpul AK lower handguards are UltiMAK compatible. Of course our ACR2 Modular railed AK lowers are UltiMAK compatible. We can’t vouch for any other. If you have an original military (inside) pattern lower, and it’s not Chinese wood, then you’re almost certainly good to go. There are some very well-made AK military lookalikes which are NOT compatible because the internal dimensions do not follow the originals. Some of the Century Arms wooden side-swell handguards are but one example. If your aftermarket handguard is not from Magpul, you may need to do some simple routing, chiseling or Dremeling to make room between the barrel and the inside of the handguard. This isn’t difficult. We sell compatible handguards here on our web site. Choose one of those, or a Magpul, and you’re good to go.
Magpul for this example has chosen to consider the untold thousands, and growing number, of UltiMAK AK optic mount users by designing their AK handguards with the UltiMAK system in mind. Kudos to Magpul for discerning the market and responding to it. Some other companies, not so much, and we of course have absolutely no control whatsoever over the plethora of other manufacturers who’ve jumped, willy-nilly, into the AK accessory business without first having done their research.
Second point: we created one of the first truly serious accessories ever in the U.S. for the AK platform. Practically everyone else in the AK aftermarket is a relative Jonnie-come-lately, and could therefore have chosen to play along and design around the existing UltiMAK system for the sake of their customers by making their products UltiMAK compatible. If they didn’t – well, oops. Maybe they can fix that soon.
Q: How come your M6 mounts won't fit Universal (or Plainfield, Iver Johnson, etc.) commercially made Carbines from circa the 1960s and ‘70s? I mean, my uncle carried one in Korea, and...
A: Firstly, no he didn’t. As stated in our product descriptions, our optic mounts fit the GI blueprint Carbines ONLY, and that may or may not be a problem for your Universal (or Plainfield, etc.), but most likely it is a problem.
Universal began production in 1961, and kept at it through 1986 (the other commercial brands existed in roughly the same general timeframe). Some of the earliest ones produced were 100% compatible with GI carbines because they were assembled entirely from GI surplus parts, but that soon began to change.
The website M1 Carbines Incorporated* explains this in detail:
“More than 426,000 carbines were manufactured by Universal Firearms over a 25 year period from 1961 through 1986. This was 10 years longer and more than three times the quantity manufactured by any other commercial carbine manufacturer. In the beginning the first Universal Firearms carbines were 100% compatible with surplus GI carbine parts, their carbines included many of these parts. As with every other commercial carbine manufacturer, as surplus GI carbine parts became scarce, Universal Firearms began using commercially manufactured substitutes. Unlike other commercial carbine manufacturers, some of the commercially manufactured parts used by Universal Firearms were eventually compatible with the Universal Firearms carbines only and not interchangeable with their surplus GI counterparts.
In 1967 beginning with serial number 100,000 Universal Firearms implemented a major design change to the carbines they produced. The design had been patented by Universal and the majority of parts were no longer compatible with their GI counterparts. The design change was significant enough that the carbine it produced was no longer an “M1 Carbine”. What makes a carbine an M1 Carbine is the use of the design and parts of the original U.S. M1 Carbine, as set forth by U.S. Army Ordnance in the 1940’s and early 1950’s. The Universal Carbine retained the overall outward appearance and ammunition of the U.S. M1 Carbine, but the internal design and parts were a hybrid replica of the M1 Carbine.”
And so it would be up to you to take your Carbine to a local expert and have him determine whether your Universal Carbine has a GI barrel or one of the commercially produced barrels. NONE of the commercially produced barrels are compatible with our optic mounts, and MOST Universals have commercial barrels.
*Source:
Q: What about my Saiga AK? Do you make a mount for it?
A: The UltiMAK M1-B is the correct optic mount for a Saiga based on the AKM pattern, of any cosmetic configuration, chambered in 5.45, 5.56 or 7.62 x 39mm (NOT for the 308 Win, which has a totally unique barrel profile).
HOWEVER; if you have the factory Sporter handguard (no upper handguard, with a long lower, and no forend cap) that handguard will interfere with the optic mount. You have several options in dealing with this:
1. Cut down the original handguard from the top, by about a half inch over a length of about four inches. This will be immediately obvious once you have the optic mount in hand.
2. Obtain one of the “bolt-on AK lower handguard retainers for Saigas” (use that as your internet search phrase). We prefer the clamshell designs, but any of them will work. That will allow you to use a standard AK lower handguard. Not all lower handguards are UltiMAK compatible, but the handguards we sell are.
3. Use the UltiMAK ACR2 tri rail forend, which of course is compatible with the optic mount. It comes with its own attachment system, so you don’t need any other hardware to make it work on your Saiga. Any of the three lengths, as ordered for stamped receivers, will work on your Saiga.
4. Use the Zhukov lower handguard from Magpul. It too is UltiMAK compatible, and comes with its own attachment system.
So you see you have several good options there.
If you have one of the Arsenal SGL model Saigas though, it is currently in standard AK configuration and you’re already good to go.
Q: What about my Palmetto State Armory AKM?
A: The UltiMAK M1-B is the correct optic mount for your PSA AK (GF3, 4, 5).
However, we have noticed this regular issue with the PSAKs:
Although they have the correct barrel diameter (and thus do NOT need our standard shim set, SH-1), the gas chamber seems to be higher over the bore compared to all of the Com Blok AKs. That, OR the carrier is a little bit different. Regardless, this unique variance sometimes causes the piston to bind as the UltiMAK clamp screws are tightened; no matter how carefully the mount is positioned side-to-side for alignment with the gas chamber.
The solution is simple; use scissors to cut several long rectangles out of an aluminum soda can. They must be sized to fit underneath the entire surface of both of the “pedestals” under the mount. Three or four layers will be required to raise the mount up off of the barrel enough that the piston no longer binds. Side-to-side positioning of the mount is also important, so with the screws only partially tightened, such that you can barely move the mount side-to-side with some force, try to find the “sweet spot” which allows the piston to traverse from the tube into the gas chamber without undue force.
Your hand-made shims must be ONLY on top of the barrel, under the mount, and NOT under the barrel as shown in our SH-1 photos. The shim(s) on top of the barrel under the mount should be sized and positioned as shown for the top shim in the photo here:
We’ve been through this with several PSAK owners now, and we have determined this little bit of shim to be the solution. As an alternative to a soda can, you can usually find brass shim stock at most hardware stores, auto parts stores, hobby supply stores, or machinist’s supply shops. Most commonly it comes in a package of assorted thicknesses. 0.015” to 0.020” (fifteen to twenty thousandths of an inch) should be about right. In that case you should be able to find a single shim of the right thickness, rather than having to stack several layers of aluminum. The brass shim stock is good to have around anyway because it has a plethora of other uses.