I have an Airsoft pistol (GE3308 1911 gas blowback) that came with a speed loader for the magazine.
Somehow I managed to loose the speed loader adapter for the magazine. 
Fortunately my son had the same speed loader and I was able to get dimensions to make a new part.
I printed the final version and put it on the loader and it worked without any fitting work.
The loader capacity is 90 and My magazine is a TM-spec.

I printed it with PLA (PETG or ABS may be better if used outside)
0.2 layer
100% infill
No supports

I used DesignSpark to create the model and will include the file incase someone wants to alter it.
Hopefully I am not the only person to loose the adapter and needed another one.