[John Sabato]

Gerben, that would have been my guess, but sometimes things are done the way the were "always" done in the old days... and I don't think any documentation exists (or at least I don't personally know of any) that tells how sheet metal mags were manufactured in Europe duing the first half of the last century...

With today's computer engineered technology, virtually all holes would be punched in any metal that gets formed cold. I managed an engineering department for a very technology sophisticated sheet metal manufacturer for two years and the wealth of knowledge that I acquired on state-of-the-art manufacturing methods was worth the meager salary that I earned while there... I was much richer for the experience.