darkker
12-03-2019, 03:53 AM
Most of this is not true, or based upon a story.
There isn't "A" alloy used for making cases, and they're isn't "A" way of making cases; there are several.
Someone tells you they "weighed" their cases, good for them; what's that got to do with volume? Do they know if they're balloon-head, or regular cases? Have they ever even heard that term?:o
We did some pressure testing a couple years ago, testing the nonsense claims of small rifle primers in the Creedmoor. Compared regular Norma cases and the SRP cases ordained by Jeebus himself (Lapua). The average weight difference between cases (again, one is a balloon head) was over 10gr different, and almost that much variance within brands. Same jump to lands, same charge, yielded?
That's right, the same pressures, and the same burning curve. Guessing and repeating stories doesn't make them true. Similarly, unless you are talking about Groupe SNPE powders, don't think QL is the holy Grail, it isn't. In fact if you are using any of the progressive burning powders, it's dangerously wrong. Fixed volume bomb calorimetry doesn't begin to explain how burning curves shift with different volumes, the point of the thread. So expecting an estimation to know actual pressures.....
If someone wants to honestly learn, and know pressures and what's really happening when you pull the trigger; buy a Pressure Trace system. Instead of paying for QL, use the money to buy an actual measurement tool. But be prepared to have your world rocked.
Most of what you think you knew, or could "tell"; is completely wrong.
There isn't "A" alloy used for making cases, and they're isn't "A" way of making cases; there are several.
Someone tells you they "weighed" their cases, good for them; what's that got to do with volume? Do they know if they're balloon-head, or regular cases? Have they ever even heard that term?:o
We did some pressure testing a couple years ago, testing the nonsense claims of small rifle primers in the Creedmoor. Compared regular Norma cases and the SRP cases ordained by Jeebus himself (Lapua). The average weight difference between cases (again, one is a balloon head) was over 10gr different, and almost that much variance within brands. Same jump to lands, same charge, yielded?
That's right, the same pressures, and the same burning curve. Guessing and repeating stories doesn't make them true. Similarly, unless you are talking about Groupe SNPE powders, don't think QL is the holy Grail, it isn't. In fact if you are using any of the progressive burning powders, it's dangerously wrong. Fixed volume bomb calorimetry doesn't begin to explain how burning curves shift with different volumes, the point of the thread. So expecting an estimation to know actual pressures.....
If someone wants to honestly learn, and know pressures and what's really happening when you pull the trigger; buy a Pressure Trace system. Instead of paying for QL, use the money to buy an actual measurement tool. But be prepared to have your world rocked.
Most of what you think you knew, or could "tell"; is completely wrong.