well jack all i can post is facts that came from actualy chonographing my loads running powders to the point that pressure signs start developing then backing off a bit. In my experience the 257 is a bit overbore for powders as fast as 4350. Also id look at the pressure that manual gives for that 4350 load then compare it to the pressure for the 4831 load and id bet there loading 4350 to a higher pressure to beat powders like 4831, 7828, re25 ect. Run those powders to the same pressure and see what you get.
I'll grant you the experiece that you have.
I am just stating the facts from Hodgdon.
75gr vmax
4381 Max 75.0 gr Vel. 3841 Pres. 51,900
4350 Max 70.0 gr Vel. 3905 Pres. 51,800
117gr Hrdy SPBT
4381 Max 66.0 gr Vel. 3252 Pres. 52,300
4350 Max 60.5 gr Vel. 3266 Pres. 52,000
It is very similiar to that throughout the weight of bullets in their data.
I am sure that different barrels will return different results.
Actually, the one powder they did push the pressure up to show higher velocity was the 7828.
The information I first posted was a direct comparison of 4350 vs 4831. Based on Hodgdon data.
Both are great powders and I use them both. Grant you, not in a 257. I have found their data to be fairly close on the cartridges that I reload.
The link to Hodgdon data is already posted in this thread if you would like to check my data.
