Any of you seen any difference in velocity between Remington 7 1/2 and CCI BR-4 primers? Im having a hard time finding 7 1/2 but ive found lots of BR-4.

In all the years of chronograph many 100's of different loads I would have to said yes there is a difference, but usually quite minor, and never totally predictable as to which is going to be faster.

It is my understanding that the Rem 7 1/2 BR primers are a magnum primer which could result in higher veocities and/or pressures. I use them almost exclusively for my SR applications but have never compared differences between them and other primers with a chronograph.

Seems I read some place the difference was in the length of time the flame was burning from primers.

Unless I'm mixed up and that's the diff between pistol and rifle primers.

From the mixng and matching on plinking stuff I haven't noticed any difference, but, since a patch hit the face of that sorry assed chrony I haven't replaced yet. So cant' say about the diff in vel.

George

Horn Harvester: I use the wonderful Federal 205 M Bench Rest primers - exclusively - in my small Rifle applications.
Its been so long since I tested these against the others that I forget the differences specifically but I do know they produced the best accuracy and are quite consistent from year to year - decade to decade.
Good luck with whichever you choose but please be sure to try the Fedral 205M's.
Hold into the wind
VarmintGuy

Without a doubt, in my Remmy PSS 223 there is a differnce in accuracy with the CCI BR primer being a more accurate primer. Not sure because it is BR but just one over the other, give me the CCI BR. The Federal 205m is also a good primer but in certain batches the cups tend to be thin.

thanks for all the info. h.h.