Guys last year I loaded up a bunch of 243 nickle plated Rem cases and I forgot to mark what type of primer I used. Is there a big difference in accuracy between primers in this cal? I have not done anything else to the cases but I will soon be loading Nosler 90 grain ballastic tip bullets with H380 and Hornady 100 grain BTSP with a powder yet to be determined. I believe that the primers are a gold color, not much help I know but if anyone has a suggestions I am all ears.sauer06

well CCI & federal primers are silver. Winchesters are gold colored, but thats all I've used so I don't know about the other brands.

Remington primers are also gold colored as well.

In an "off the shelf" hunting rifle, either sporter or varmint..NO DIFFERENCE to speak of for the most part, sometimes you'll find a barrel that does like one brand over another but there's so much "SLOP" in the chamber cut and neck clearances that for the most part you can't overcome those to actually see how much of a difference primers can make.. now with a great bench chamber cut things are totally different.. I can see change in anything I do in my Borden cut PPC chamber..amazing differences sometimes..

You may also have to adjust the charge somewhat for the different primer.

Safety wise from one brand to another you should be fine, staying within the same type of primer (small rifle, large rifle, etc.). As others say, fine adjustments may need to be made for exact performance comparison. I would be very concerned though if you are unsure of using magnum vs. standard primers.
Most reloaders maintain a log book. Every batch of rounds is inventoried with type of powder and exact charge wt., primer make and #, Case trim length, projectile make, wt. and style, overall cartridge length, and date loaded. A sticker or tape on the cartridge box listing the same info is your 2nd check.

X 2 what Daveboone said
I will also take a colored felt pen to the primed case. Red mag green standard. It also helps with identifing caseings when shooting with others.