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Remington primers

Need more info bullet weight being first, rifle specs would help too.

As for rem 6 1/2 they're a standard small rifle primer so if you're already running this load with another primer, then yeah you should be safe, but you should always back off your load a touch and then work back up while checking for pressure signs to be sure.
 
To help prevent slamfires and ruptured primers you should only use small rifle primers in your AR15 that have a cup thickness of .025.

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CHOOSING THE RIGHT PRIMER - A PRIMER ON PRIMERS

Primer Info & Chart + Milspec Primers for Semi-Autos & Other Primer Applications