Whats the difference on these two primers.

[The Duke007]

I have a couple cci benchrest 2 large primers left. I have been using them for about three years now and very happy with the way my rifles are shooting. I have been looking everywhere for them and cant find them. My local gun shop has the federal large rifle match primers in stock. My question is if i use the same load and just switch to federals will my point of impact change or anything else would change?

 

[Broz]

The short answer is yes. A simple primer change can change velocity, pressure, ES, and group size. The only way to know if they will work is to back the load off and work it back up to see.

Jeff

 

[SidecarFlip]

+1 on Jeff's explaination plus cup heights and flame patterns vary between manufacturers and even between lots, one reason I suggest buying primers in full case (1000) quantity and not by the individual pack.

I found that out real quick tweaking a 209 inline.

 

[tomt]

Check this out, pretty amazing.
Primer Flash Test Photos

So as stated work back up.