Hi Doug,

In answer to your question, I put 9.2 grains of Unique into a fired and unsized Remington .357 case. The powder came to within .4 (four tenths) inch of the case mouth. With a sized case the powder would have been a bit higher. And, of course, results could be a bit different for whatever case you're using.

I don't have any 125s lying around but I don't think you're going to have too much airspace between powder and bullet. And if memory serves me, 9.0 grains is what Skeeter recommended with a 125.

Hope this helps.

Mark