Re: Big difference in accuracy based on primer brand?
I answered based my experiences and 1000's of rounds down range in various calibers and numerous primers tested. My reloading practices and test methods are largely based on BR shooting. Groups larger than the mid .2's or scores lower than 197 out of 200 will have you jockying for 2nd place. Most of the suggestions I give are based on that.
<span style="font-weight: bold">You failed to give your caliber of choice so my response was kept short.</span> Share your caliber and we can give you more detailed information.
It seems for me that with the Hogdon Powders of late, the CCI primers are giving the best results. With the IMR powders of past, Federal gave the best results. The WLR & F210M primers run very close to burn rate and given velocities when either is used and most times can be exchanged with each other. Several years ago I performed a velocity and accuracy test using a 7mmRM, 150 grain SGK bullets and H4831. This test was to determine, if only in my mind, if primers really made that big of a difference. The primers tested were the F210M, F215, WLR, WLRM and the Rem 9.5M. The primer that gave the highest velocity also gave the best accuracy, the F210M. This primer beat all others by 50fps and produced .3moa accuracy at 100 yards. The test confirmed what I already knew, primers do and did make a difference. The F210M is the main primer I shot for several years until they became almost extinct. I then switched to the WLR and CCIBR2. The BR2 is a milder primer than the others and requires a bump in the load of .2 to .3 depending on the caliber. My 6XC loves the WLR's while my .260 and 7-300 wsm love the CCIBR2's. My 6 Dasher and 6BR shoots the CCI450's the best although the only other primer I've tested in those rifles has been the F205's with 107SMK's
While testing my 7-300wsm I started with the F215's and quickly came to the realization that they were junk in that particular rifle. I switched to the WLR's with RL-25 and then to the CCIBR2's with H1000, the rest as they say is history.
300 Jarrett loved 84.0 grains of RL-25, F215's and 165 NBT/175SMKs
7mmRM #1 H4350/F215's/150 SGK's
7mmRM #2 H4831/F210M/150SGK
7-300WSM H1000/CCIBR2's/180 Berger vlds
2-.308's H4895/CCIBR2's/175SMK's
6 Dasher & 6BR Varget/CCI450's/Berger 105 vlds
.260 H4350/CCIBR2/130 Berger vlds (hated 210's and WLR's)
6XC H4350/WLR/Berger 105vlds (hated CCI primers)