I kinda was wondering when some folks might refer to the SAAMI or the CIP spec on the 9mmx19. Kinda different philosophies don't you think?
When I started shooting Lugers, vintage ones back then; I acquired a fairly large quantity of 9mmx19 range brass. Being a reloader, I measured a large quantity to see if they met SAAMI specs for a case, 754-10. Only a very, very small percentage did. Of course, I saved them for the Lugers and they shot/functioned very well. The number of perfed cases, all kinda short, put me off on those for a while until I found a use for them.............simply a custom barrel for that batch of brass.
I like PTG, Dave K. makes good stuff and has helped out many times; knows his stuff.
I always worry about headspace numbers, even more about gapspace numbers, be that is part of careful reloading for oneself. Yeah, a Luger will come apart like G.T. described, from a too deep a chamber(for whatever reason). Always a bit embarassing to blow something up, but it does happen. Kinda like Dr. talk, best cure is never to get sick type of thing. In the firearm world, it pays to pay attention to numbers and measurements.
There is a school of thought that only uses a go gage, and a roll of scotch tape. Purely opinion on that. Some in the real business will buy the no go and the field kinda for a double check, for different reasons(liability is one, safety is another). If you find someone that is lackadaisical about measurements in your build, one might look around a little.
Always heard that the SAAMI is a guide, trying to make things compatible. Tis good to have some specs don't you think?
Gages are expensive relatively speaking. Some guys make their own from specs, but then they know what materials etc etc.
When I do my own barrels, I am around the short end of things, ie the go area plus a bit. The bit varies from smith to smith.
I am most pleased that G.T. did not get hurt in the happening. Things happen to us all, some we caused ourselves for one reason or another, or then the real special deals where you cannot put your finger on it, a mystery of sorts. I extracted a case one time, high power rifle, it had blown gas past my face, and the primer fell on the ground.........specialized case in benchrest, something different about that round, but to this day I still do not know what that was.
I have found like others, that in changing parts around, you have to keep in mind what the influence of such is to the loaded round and firing said round. Headspace comes to mind, as does gapspace(case exposure unsupported).
A most interesting thread, my compliments to G.T. for starting it.
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