Pete, thanks for the detailed writup. It's good advice not to use lead recipes for the same weight (mass) of bismuth shot.

Pete my question is what the effect on pressure would be if I substituted Nice Shot for Bismuth using Sherman Bells info. The loads listed for BISMUTH are:
1- Rem hull, 1 1/4 oz. Bismuth, 29grns 7625, SP10 wad, 24 grns PSB(or not), roll crimp--1083fps/5900psi.
2-Fed hull, exactly the same components except 30 grns 7625 for 1084fps/5800psi.

What would the effect on pressure be substituting Nice Shot for Bismuth???

Thanks, George

I don't know, substituition of Nice Shot for Bismuth does not make sense to me when the folks at Nice Shot tell us it can be substituted for lead in any published lead recipe BUT you must add an additional 1500 psi to that lead recipe when using Nice Shot.

Given that, why would you not choose one of the Sherman Bell recipes for lead using a Rem hull and SR7625 powder? I see some on the 10ga spreadsheet that would be about 8000 psi using Nice Shot (and that is with a folded crimp).

Pete I do currently load Nice Shot using lead recipes. I was just wondering would the relationship, pressure wise, would be between Nice and Bismuth. I reread my original post and it should have read; I am currently "LOOKING "to load----. It would seem that the switch, in the above loads, should be equal or less pressure when using nice shot??? I know this is all speculation and we won't know until some actual pressure tests are performed. George

I am curious, since there are published lead loads with known pressures using the components you listed why would you like to substitute the Nice Shot in a Bismuth load for? What are you trying to achieve, lower pressures?

I have both Nice and Bismuth on hand and curiosity took hold of me, and pressure was a consideration especially if a 6 pt crimp was used. I would like to keep psi under 7000 and was looking at possible ways to achieve that using Bells data swapping out combos of shot and crimps.

I don't know that you can achieve that goal of 7000 psi. I see a 1 1/4 ounce load of lead using 29gr of 7625 and folded crimp in the Rem Blkltr hull, it develops 5900 psi. 1 1/4 ounce of Bismuth in that hull with 29gr of 7625 develops 5900 but uses a roll crimp. My guess, and it's just a guess is you would be around 8000 psi with 29gr of 7625 and Nice Shot, probably lower if you use a roll crimp. You would have to send it out for testing to confirm it.

Pete are you saying that Nice Shot would have higher psi than Bismuth? It would appear that 5900psi minus approx 600psi for roll crimp plus 1500psi for nice shot should be about 6800/7000psi, or am I missing something? I've only recently started to load for shotshells(0nly 10 ga so far) and I'm sure that there must be more variables then I'm familiar with at present. That's why I'm asking I need to be educated and enlightened. Thanks.

The difference betwen equal weights of Lead vs Bismuth is the height of the shot column and amount of surface area in contact with the bore. 29gr of 7625 is 29gr of 7625. With the lead load you generating 5900 PSI. Nice shot has the same size shot column as lead, but because it's harder than lead it generates more pressure as it has a harder time squeezing down through the forcing cone. This puts you up around 7400 psi with a fold crimp. Using a roll crimp will drop pressure, maybe 600, maybe 800 maybe even a 1000. Only testing will tell for sure. I would stay with the low pressure lead load and add 1500 psi. I can't imagine a sound Parker 10ga having an issue with an 8000 psi load. If you go too low you risk bloopers, especially in cold weather.

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