I generally have never found the strechtching method to be very good as the springs not seems to be very good.
But I remeber one magazinearticle about it some years ago where the author stated that the springs should be heattreated in the owen afterwards.
I belive he put them in for 1 hour at 200 celcius.
Personally I dont use original mags anylonger and today relys totally on Tripple K mags.
The tripple K's are extremely cheap and works very well.
Regards HÃ?Â¥kan
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