I'm forced to shoot a lead free bullet out of my 257 roberts and decided the barnes TTSX's would be a good place to start. I shoot a m77 with a 20 inch barrel and for 25 years have shot sierra 120 grain hpbt's at 2700 fps. 400 yards is about MY limit and this combo has always worked fine, when I do my part.
I tried the 100 grain TTSX the other day and accuracy was great but could only produce about 2800 fps, with a few different powders before I got pressure indicators in my rifle. Is 2800 going to be enough to reliably open up the 100 grain at 400 yards or would I do better at 400 pushing an 80 grain at maybe 2950? The copper bullet is brand new to me so any real world insight would be appreciated.
What powders were you using? That speed seems really low.
