A 1970 Hercules catalog arrived in the mail yesterday. It contained the same load data as the 1968 version I obtained. The difference being the 1970 catalog gave specifics on hull type and primer wheras the '68 version did not. Neither cites chamber pressures. Unique is looking like it is a very good powder for use in composite barrels with 1 1/4 ounce lead loads for sure and my intuition based on multiple sources tells me 1 3/8 ounce and perhaps 1 1/2 ounce loads could be tamed to sub 9000 psi with it. I am now awaiting arrival of some mid to late '70's Hercules guides with the hopes they provide further details especially chamber pressures.
If my personal calculations are correct (and I believe I am close) my home brewed crow load of 2 7/8" Fed Hull, Win 209 primer, 27 gr of Green Dot, SP10 wad, .135 NC and folded crimp should be giving around 1150fps and 7600 psi. This will have to be sent out for testing to confirm. My calculations also indicate using 29 gr of Unique in this load should bring about 1220 fps and 7200 psi, again needs to be sent for testing to confirm.
If you decide to use these loads it is at your own risk because they are based on educated guesstimates
As EDM used to say, investigation continues.
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