Winchester claims their 30 Luger load with 93 grain hardball has a muzzle velocity of 1220 fps from a 4.5 inch test barrel in a test fixture. How ever I find that either this is optomistic or else the air over my chronograph is particularly thick stuff. I have to use at least six inches of barrel to get it near that velocity. Won't get close from a 4, 4.5, or 5 inch barrel.
Winchester's listed hand load for the 30 Luger is quite unlikley to cycle the action as Winchester calims it runs the same bullet from the same test barrel at around 1050 fps. Hopeless!
Right now I am sorting out recoil springs versus loads. Later on I'll try to sort out loads.
We have established 25 lbf as the absolute minumum for the recoil spring without regard to load. Below this the spring will not reliably close the action. It is possible for the action to stop almost closed but not locked and then fire from that position. So too light a recoil spring can be a safety hazard!
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