I've been using magnum primers (CCI brand) for all my reloading for the 243, 280 Remington, 308 Win and for my 8mm Remington mag for the last five or six years. I just don't like stocking different types of large rifles primers. I'm getting excellent accuracy with them all. Don't know what else to say...
I would suggest you start under your max loads and work up your loads again, that what I did.
I only shoot one small rifle, the 204 Ruger and I use CCI BR-4 primers in it.
Same with the handguns. I use small pistol mag primers for the 38/357's and large mag pistol primers for the 41 mag and 44 mag and 45 long Colt even for the light loads for wadcutter 38 practice loads. All seem accurate and I've only one style of primers for each caliber.