I just got my Encore barrel (26") in 6.5-06 Ackley and it has a 1-8" twist. Unfortunately, velocities are 150 to 175 fps less compared to identical loads in a 24" barrelled rifle in the same caliber, BUT with a 1-10 twist (both using 120gr bullets). Since my velocities are lower, is there any advantage to the 1-8 twist over the 1-10?? Yeah, I can shoot 160 gr bullets, but I don't plan to. Advantages???

only one i know of is that you can stablize heavier bullets and shoot them better, but you said you wasn't going to shoot heavier so I don't know that there would be an advantage. However, you always know if you wanted to , you could handle it better and 100 fps or so isn't going to loose you much. Good Luck.
Whitey

It isnt the weight you are stabilizing, its the length. The formula is: T=(150X(D�))�L
In other words, the optimal twist (T) is equal to 150 times the diameter squared, divided by the length.
Notice that there is no weight in the formula. It is called the Greenhill formula, if you do a Google search on it, you will find a site where you type in the length and diameter and it figures it out. If I recall right, the formula is for barrels over 20" and doent apply to pistol.