I have been reloading for over 40 years and the primers make a difference . I tried different Primers on my accuracy loads and have seen the difference in group spread . I only use Wolf Primers L.R.for all my loads . Rem.7.5 small Rifle Primers in all my smallers Cartridges , I found out During the Obuma Momma Time because of the shortage so I had to use what was available .I learned also From David Tubb , Listen to what the winners Use , End of story