I trying to figure out if my numbers are correct before ordering neck die bushings. The cartridge is Winchester brass in .300 WM. A loaded round (HSM) is 0.334" and a once fired case from my rifle measures 0.341", a difference of 0.007. I was going to order a bushing in size 0.333" which is .001" smaller. However, I just came across the following regarding Redding bushing sizes from Redding. "Redding has found that when you have cases with neck wall thicknesses on the thin side of the SAMMI tolerance, your fired case will measure considerably larger (.006" - .010") than your loaded rounds. In these circumstances, Redding's tests have shown that a bushing .001" larger (than the loaded round) may give you the desired bullet grip." Since the difference in my measurements fall into this category and if I were to follow Redding's recommendations then I would need to buy a bushing that is .335" (.001") larger than my loaded round. What are your opinions and what type of measurements are you guys getting from your .300 WM rounds? Thanks!