Marc,
Contact BPI for their "10 GAUGE - 28 GAUGE LOW PRESSURE LOADS", Library # OOBLowPSI. Their loads for lead start at 7000 PSI.
For Nice Shot I selected a 6500 PSI load and added 1500 PSI due to shot hardness as advised on the Eco Tungston website. I need to contact BPI for the ITX safety factor. This is the fun part...
This ITX load is hot for old guns but my Little Friend Ten, a straight grip Damascus GH 10 was proofed in England for 3 1/2 tons or 10,500 PSI. This Parker is full pound lighter than my aforementioned DH 10. The DH of course has thicker barrels. Barrel thickness (and condition) is the key.
BPI L0AD#100907-2465-4/2/BB
HULL: FEDERAL 10ga. 2-7/8” (2.85”)
PRIMER: FED209A
PROPELLANT: HODGDON UNIVERSAL CLAYS 33.0 Grains
WAD: Helarco VP100
SHOT: 1-1/4 oz ITX #4 or #2, or BB (546gr.)
BUFFER: none
ROLL IMP: For over shot card use a COS12 or a N710 card.
Result: PSI 10500 FPS 1435
Wow! 1435 FPS...that's fast! So, back it down a few grains and switch to a Cheddite or Win 209 primer to lower velocity to 1200 FPS. The pressure should drop.
Mark
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