What you need to consider is that the web of the 10mm Mag if different from the 10mm can cause excessive pressures as it occupies powder space. I am not familure enough with the 10mm mag cases to advise if it is thicker than the 10mm.
The 40S&W case is the small primer making the small difference in the web but I have seen more 40's blown out than 10mm!
If you live in the real world of safety, you will live within the design of the 10mm cartridge. Therefore if you push it will push back!
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