Well, the decision to try them is strictly yours. I will tell you what I would do - I'd go ahead and try
one. If that one worked, I'd try another. When I have tried all 100 and they all worked, I'd say it's safe to do.
It's sort of like testing all your matches before you go into the wilderness.
Just be aware that you are using old primers that are a little less powerful than the suggested primer with a powder that is a little harder to ignite. I checked about 6 different manuals, all of them except Speer said standard LR primers are ok with W760. I had only looked at the Speer manual originally.
You've probably figured this out already - it is a good idea to keep your pistol and rifle primers in separate locations. I keep my rifle primers and rifle powders together on one shelf (but not too close together) and the pistol stuff on another.
[This message has been edited by Mal H (edited February 21, 2000).]