I'd be interested in getting some feedback from HOWA 1500 Win .243 owners on the maximum COAL measurement on their rifles. I don't have a gauge but used the methods described on the ballistics studies website Determining COAL
Method 1. gave a result of 2.630", Method 2 gave 2.645". Using Sierra Pro Hunter 1540 bullets.
I have a problem with my HOWA in that the chamber max COAL is less than the "min coal" as stated in the reloading manuals. I'm reloading PPU brass with Sierra Pro Hunter (1540) using H4350, (39.2grains). The recommended min coal is 2.650", If I size to this and chamber the round the bullet is pushed back and remeasures at +/-2.645", meaning the bullet is hard on the lands with the resulting concerns on pressure and safety.
I have raised this with the supplier and am awaiting feedback.