What are you loading it in? If in a smaller cartridge like 32-20, 38/357 I wouldn't worry about it but in a bigger capacity cartridge like the 38-40, 44-40 or 45LC there would a a noticeable difference. I load the FFFg size 777 in the 357 because i didn't read the instructions before I had already tested and found a good load in the 357mag. After finding they do not recommend the FFFg in cartridges I figured the 357 is a very high pressure round and I wasn't gonna worry about a moderate increase in pressure. I would think it might be significant in the larger capacity cases of the BP calibers. I still only load the FFFg as it meters well and works fine for me.