I would agree with you on the older WW standard / mag primer working with the more temp unstable powders of the time such as H-380, RL22/MRP, H-4831,and H-4895 being more consistent for a hunting round especially in cold weather. Most of my tests were done with a 25.06, 243 Win, 22.250, and 220 Swift.
For the 25 with RL22/MRP I found that the WW and the Federal standard gave excellent results with the heavier bullet weights ie. 110 -120 in the 3/4 - 1" range which was more than acceptable for the purpose. With the 243 in the 85- 100 range the results with 4831, H-4895 were the same.
However for the lighter varmint rounds I found that the CCI standard primers gave me a more consistent grouping with 380 in the 250 and Swift, and with 4895 w/70-75 grain bullets in the 243. If I was going for pure accuracy in the varmint calibers I switch to a BR or gold medal match primer.
Unfortunately I have not really done any testing on the variances of the large rifle primers since about 05 as I have been into shooting and testing accuracy of the 223 in a pair of Coopers since about 07, and my loads for the others have been pretty much been settled.
Hope this helps.
Last edited by Swifty52; 09/03/15.
