SP vs SR Primers

[tgwillard]

I read in one of the posts here that SP and SR primers are the same, unlike LP and LR. Is this true.

[OKFC05]

Same size, thicker metal on the rifle primers. Some of the ultra hot pistol loads use rifle primers. Would not try it if you have a light strike.

[epj]

Same physical dimension, but a little more bang. If substituted for SP, powder charge should be reduced and carefully worked back up if you are anywhere near max load. Cup is a little harder also. May need a full power hammer spring. Note, LR and LP are NOT the same physical dimension.

[m1gunner]

Do not use SP in rifle loads, esp autoloading rifles.