What brand are they?
As you now know pistol primers are shorter, so if they are fully seated ...... depending on the firing pin they may not ignite.
I have used Winchester large pistol primers behind full loads in 308 ....( read 50 grains W760 under 155's ) no problems, they do tend to back out to the end of the case face.
But that is the only difference between LR and LP I have seen, its in a beefy Banard action though.
I wouldnt encourage others to do it, but I have no problem with it.
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