I just bought a stormlake 357sig barrel for my g23. I received some 124xtp and starline brass to load for it today. I've been reforming 40sw brass till I got the sig brass. Today I tried to measure the free bore between the shoulder and rifling and couldnt do it. I loaded a 147 gold dot dummy round as long as I could(1.330) without touching the rifling. How much is too much? The barrel shoots fine and is accurate. Wanna kill these ads? We can help!