Here is a video to convert the standard magazines to 15-round magazines. This should work with either the GSG or the SIG:

 

 

http://nictaylor00.blogspot.com/2012/11/gsg-sig-1911-22lr-basepads-and-followers.html

i did a lot of web searching on these followers.. (i don't know if the above product is brand new (november 2012 date) but you can find a lot of stuff on boards where these things fail alot.. they weren't feeding.. i think the springs don't have enough strength to push all the way up..

 

but again, i don't know if this is a new/better one..

Alot of people had trouble with those followers, some had no trouble. CW Accessories has released a new "power spring" they claim has solved the problem. I have the followers sitting in a bag since I did have issues with them. I will probably order a couple of the springs to try out but, I'm in no rush as 10 rounds is the limit in the OBRAMS matches that I bought the gun for.

 

http://www.cwaccessories.com/Products.html

I like it, but as noted some have problems, some don't. I'm thinking, unless you put longer springs in, it's probably going to be hit or miss especially with well cycled springs. Now if OBRAMS or some other 22lr gun games were able to take advantage of the additional rounds, ill probably skip them for now.

 

 

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