jackssmirkingrevenge wrote:So the sabot is also the "burst disk"?
What mix were you shooting at?
The shear skirt is incorporated into the base of the sabot, yes. It's not shown in the FEA output though.
This was with 2.75 : 7.24 propylene / oxygen at a pre-ignition pressure of 12.8 bar (absolute pressure - the nitrogen content was ~ 0.1% due to pre-shot purging with propylene). The targeted maximum pressure was 4500psi.
@Brian:
It's steel plate, but not nearly so hard as would have been used for armour. I wouldn't call this a beast - it's a little over half as energetic as a 12 gauge shotgun firing slugs.
The brass fitting isn't really damaged - the sealing faces and bore are very smooth, and the barrel connection is sound. It's just ugly on the outside.
Incidentally, this breech can seal in both directions. Any guesses on why that is?

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