From what was described, either far too little powder or no powder at all in that cartridge.

From the standpoint of economics, the advice given is to use small charges of fast burning powder. That's great from the view of a bean counter, right up until a case gets no powder or worse, a double charge of powder. I used to be one of those who subscribed to the economics of reloading. It was the 80's, I had a part-time job and I was in college. Money was tight and I enjoyed shooting... a lot!

I'm quite a bit older now and maybe a tiny bit wiser. I no longer subscribe to using tiny charges of the fastest powder for a given caliber just so I can save a dollar. Fast burning powders have their place, but I prefer medium burning rate powders like AA#5 and Unique. Even when loading to mid-range velocity, they fill about 1/2 of the case volume, so it's easy to see powder in the case and a double charge is very easy to see.

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VCDL, GOA, NRA