benchracer
Well-Known Member
- Joined
- Dec 18, 2009
- Messages
- 1,659
I wonder what we could get out of RL 17 if we went to 65,000,psi? Does quick load allow this? I have a pound to try with 208, amax .
Yes, QL allows that. There is, of course, a velocity increase to be had from doing that. The problem lies in where the accuracy nodes will fall with the bullet chosen and the 22" barrel length. In order for the top accuracy node from a 22" barrel to fall in a place where the higher pressure ceiling can be used, bullet weight has to be reduced to 168 grains.
With the 180's, the next lower node has to be used, which will appear around 2700 fps with RL-17 from a 22" barrel.
Barrel lengths of 24" and 26" have nodes appearing in favorable velocity ranges with heavy bullets. Some of those combinations have the high node showing up around 60k, which can be done without pushing pressures higher.
QL shows the same 180 SGK reaching the high accuracy node @ 2930ish and approximately 63k psi from a 24" barrel, using RL-17.
From a 26" barrel, the same combo comes in @ 2935 and just below 60k psi.
While a 22" barrel is capable of pushing a 180 SGK to just below 2900, using RL-17 and a pressure limit of 65K, it falls short of reaching the next accuracy node, which falls around 2930 and pushes pressures dangerously close to 70k psi.
In contrast, pushing a 168 Berger Classic Hunter from a 22" barrel, using RL-17 and a 65k psi limit, the high node is reached @ 2960ish and 63k psi.