G9 Mag Adaptor, Pics and Installation thread

I will be posting some of the pics and comments which I think would be helpful to people who are attempting to install our G9 units.

However, I know we have a great many talented and knowledgeable people here on CGN. Add your pics and tips to this thread please, you might be able to help someone out.

My hope is to establish a data base of information to make the installation as easy as possible for those wanting to add a G9 to their SKS.

All pics and written descriptions copyright of Magwedge Industries and Dean Roxby.

Receiver mod pics

The receiver mod is probably the most daunting of the changes you will need to make to your rifle. Here are a few pics to help make it easier to understand what to do. Essentially you are creating enough space for the XCR magazine to fit into the receiver.




Top pic shows an unmodified SKS receiver from below. The "bullet ramps" are clearly visible.

Bottom pic shows a modified receiver. Front and sides of ramps are milled back. I would give dimensions but it seems to me every one of these fittings should be treated as a unique custom project. The main idea here is to allow an XCR mag to just fit into the space after all mods are complete.



Perodically check fitment as you go.

Pic illustrates that you can get a rough idea how much to cut without having to assemble the whole unit every time to check.

Trigger group modification

This one is pretty easy, just remove enough of the front tangs to allow the magazine to easily enter the adaptor. Trigger group at the right has been modified.




Here we are trimming the tangs in the milling machine.

Bolt Hold Open (BHO) modification

Marcus (the original inventor of the G9) suggests shortening the BHO by 0.2". I imagine he means that you should remove this amount from the bottom of the "nose" of the BHO, but I found that we had to remove other material as well. Bear in mind that Marcus is working in the USA and is able to modify his magazines as well, so that may be the source of the difference here.

Here is a BHO in original condition. There can be variations in shape so again, we must treat each installation as a custom job. The main idea here is to remove just enough material to allow the BHO to function.


Here I marked in red the areas we ended up milling away. I would start with the underside of the nose and proceed from there to remove only as much as necessary from your BHO. Try to see what parts get in the way of the proper function of the BHO, and only when you are quite certain, cut away metal. I would treat any measurements given with caution, and as rough guideline only.



A BHO in the rifle. Mods have been completed as can be seen by the fresh cut metal. I see now that I forgot to mark the front tip of the nose as slightly cut back. We found out sometime later that this needed to be done as the BHO was not operating correctly. Best to leave this mod until you can observe a problem with functioning and then cut only as much as necessary.

The pin that needs pressing out to remove the BHO is visible .... some seem to be very difficult to extract. Beware of losing the spring under the BHO, as once retaining pin is removed the unit can pop out with considerable force.



Re-installing the BHO: water pump pliers work very well for putting even pressure on pins that need replacing.

Bolt modification

The bolt modification is necessary for the "Canadian installation" of the G9.

The sides must be shaved to allow the bolt to pass cleanly between the feed lips of the XCR magazine. We also found that the bolt would bind and fail to go fully into battery unless a small groove was cut in the bottom of the bolt to prevent the front edge of the mag from exerting upward pressure on the bolt.

Any modifications to the bolt must be considered with some care. If you search around you will see a great many versions of this modification. We chose to alter the bolt as minimally as possible, and to above all avoid damaging the front face of the bolt. The bottom groove we cut lines up with the front edge of the magazine and is set back a comfortable distance from the bolt face.



Top pic shows the view of the bottom of the modified bolt. The sides have been shaved and the groove we cut is visible near the front of the bolt.

Middle pic shows a side view of the same thing.

Bottom pic shows the result we are aiming to acheive: the bolt passes freely between the XCR magazine lips. Note notch in bolt bottom just above the front of the magazine. This allows the bolt to go into full battery as there is now enough clearance with front edge of the magazine.

Finishing touches

A comparison of an unaltered rifle and a modified receiver and a modified stock.



We added a set screw to our version of the G9.

This is inserted after the installation is complete and the rifle has been "function tested" with snap caps or other inert ammunition. The effect is to secure the assembly and allow for fine tuning of the installation. Set screw should be installed firmly but beware of over tightening as a lot of pressure can be put on a part with a screw. Light locktite may be used if desired.



What we hope to end up with: rifle and G9 assembled as a working unit.



Kwikrail not included, but highly recommended ...

I would like to take his place ;-)

Grin said:

I would like to take his place ;-)

Click to expand...

If this guy is really on the pre order list and drops out then I would consider it, sure.

I just pm'd him to find out, now we wait ...

Ok., lets wait.
Question about installation. Is this bolt mod allows mag drop free?

That's a hell of a lot of modification. Should consider selling them kit installed. Most people won't have the tools or know how to utilize this product.

Rock Out w/ Ur Glock Out said:

That's a hell of a lot of modification. Should consider selling them kit installed. Most people won't have the tools or know how to utilize this product.

Click to expand...

Some dealers plan to have them have them available pre-installed.

At this point I am not a gun dealer so I will not be able to sell on this basis.

I must say that the amount of modification necessary has been known for months so I am a little surprised at the reaction of some.

Grin said:

Ok., lets wait.
Question about installation. Is this bolt mod allows mag drop free?

Click to expand...

Yes it allows the mags to drop free.

I do not see this modification as too complicated. The key here is the adapter, I followed the development on the adapter by Markus and hoped it will be modified for Canada. As i get my hands on one, I will make the detail pictures of modification using basic tools as I do not have milling machine - dremel and files

MagWedge Industries said:

Some dealers plan to have them have them available pre-installed.

At this point I am not a gun dealer so I will not be able to sell on this basis.

I must say that the amount of modification necessary has been known for months so I am a little surprised at the reaction of some.

Click to expand...

Well I'm "some"...

And these are your words..

"The other reason that the mag mod is popular is that you CAN return the rifle to its original state .... this is no longer the case once the receiver is modified."

After the mod you've provided, the rifle can be returned to its original state? Doesn't your instruction include modification of the receiver?

Grin if you want one at the pre order price email me at magwedge@gmail.com with your contact info.

I would be very interested in seeing how you approach the install using basic tools and I think many out there feel the same.

As far as I am concerned I do consider the modification fairly advanced, and I really do not care if a few guys get cold feet and cancel if I say as much.

From my point of view I am doing my due diligence in posting as much detail about the installation process that I can. I am not interested in selling a bunch to folks only to have them ask for their money back later because they "didn't know" how much was involved.

Here it is out in the open and for the most part I have taken no money except for a few guys who were ready to take the plunge as soon as possible.

Terry135 said:

Well I'm "some"...

And these are your words..

"The other reason that the mag mod is popular is that you CAN return the rifle to its original state .... this is no longer the case once the receiver is modified."

After the mod you've provided, the rifle can be returned to its original state? Doesn't your instruction include modification of the receiver?

Click to expand...

Terry I have never said that the G9 mod allowed the rifle to be returned to its original state. The receiver mods as shown here are for installation of the G9

The G3 mod does allow a return to the rifle's original state .... but the G3 is a different system and one that we are not producing yet but plan to have in production shortly.

With all due respect I think maybe you have confused some things.

MagWedge Industries said:

Some dealers plan to have them have them available pre-installed.

At this point I am not a gun dealer so I will not be able to sell on this basis.

I must say that the amount of modification necessary has been known for months so I am a little surprised at the reaction of some.

Click to expand...

Indeed, and its not meant to be any slight against the product. I'm just coming into this one, so my suggestion is solely based on opening the product up to a larger market. It appears thus far to be a very superior aftermarket option and sometimes to get that kind of quality and fit working together it requires modifications beyond what the "average" person can perform and/or has the tools for. I myself am interested in this product but am in the position, frankly, of not having the tools or knowledge.

Rock Out w/ Ur Glock Out said:

Indeed, and its not meant to be any slight against the product. I'm just coming into this one, so my suggestion is solely based on opening the product up to a larger market. It appears thus far to be a very superior aftermarket option and sometimes to get that kind of quality and fit working together it requires modifications beyond what the "average" person can perform and/or has the tools for. I myself am interested in this product but am in the position, frankly, of not having the tools or knowledge.

Click to expand...

No worries ... watch for the G3 it may be a better option for you.

Can I load an entire 10 round stripper clip Into one of those XCR mags once this mod is done?

Not sure about loading stripper clips as these are AR15 style magazines but they will hold 10 rounds and if the adaptor is properly properly installed it will shoot reliably.