I agree completely that the primer pocket is an important part of the process, but I would think that it might be one of the easier things to change (from Berdan to Boxer) in the process. The flash holes are usually drilled or punched, so that would be easy to change, and I suspect that however the anvil in the case is formed in a Berdan-type case, it would not be too difficult to eliminate. It shouldn’t be too hard to change tooling to accomodate a slightly different diameter primer pocket either. I don’t really know this, I will admit, but I have some idea about how cases are formed from the visit to Bell’s factory in Michigan, where we spent the whole afternoon with one of the egineers with no one else in the plant but him, myself and one other collector. I also learned what a good engineer coupled with a good machinist could do! Needless to say, I asked a thousand questions - probably drove the poor guy to drink! I also visited FN and saw some pretty modern, highly automated equipment, but it was for 5.56 x 45mm (.223) production. As I recqll, that stuff was made by Fritz Werner Co. specificaqlly for FN. There wasn’t really anyone around to ask very technical questions of.
I have 19 specimens of Israeli 9mm ball made before 1949, starting with unheadstamped specimens with no primer seal, green primer seal, and white primer seal. I could not see any appreciable difference in bullet ogives, except for one with a slightly flattened tip, probably due to some resistence to seating I would think, since the round appears to have never been through a weapon (nt magazine lip scratches on the case, feed ramp marks on the bullet, etc.). The primer crimps are all circular except for one “A E 8” headstamped round, which never had a circular crimp, but has three large triangular crimps. This is not a scarce variant. I have seen it often. However, the circular crimps differ somewhat from round to round, with some with a wider crimp than others, and many badly off-center. We have also observed Winchester circular crimps hit off-center. this is one of the reasons that we believe there may have been a mixture of machinery at this clandestine factory. The Israeli accounts of Polish machinery simply cannot be dismissed out of hand, but some of the features would indicate American production methods, at the least, and probably American machinery as well.
I have Winchester cartridges of the WWII era (I have no military rounds that I can tie to the immediate post-war period. It was not an American military round at that time) and most have a circular primer crimp, but I have one without primer crimp made for the Dutch East Indies and specimens made for China with a four-stab primer crimp.
My understanding is that they made the primers at the Kibbutzim Hill factory. I don’t recall where, but I was recently involved in a discussion of that exact subject, where I hypothesized that the primers were smuggled from the United States, and that is why they chose to make the cases Boxer. I actually believed for a long time that the cases were made in the U.S. and only loaded in Israel, but I know now that is wrong I was told flatly that I was wrong, and that the primers were made clandestinely in Israel as well as the cases, powder and bullets. I don’t know the truth of either theory. There is still plenty to be learned about this ammo. Unfortunately, I had poor response (actually “no response” would be more accurate) to letters to Israel - IMI primarily, I wrote many years ago asking questions about the production of this ammunition for an article that I never wrote, since I couldn’t obtain factual information from an indisputable source. It was at a time when a lot of the ammo came into this country and I went from few Israeli 9mms to a fairly extensive selection almost overnight.