Pressure differences Winchester primer vs CCI primer

[MaineGuide35]

I'm knew to reloading and Nosler forum, first post. My first question is, I'm loading 270wsm 130gr BT's. Using Nosler book minimum load 59gr. of IMR 4350, the book calls for WLRM primers but I have CCI Mag primers. Which primer creates more pressure? Using CCI primer should I start lower, higher or right on the minimum recommended powder load? Also for the 30-06 spring. 180gr NP using minimum load 51gr. IMR4350, same question as above WLR vs. CCI ? Differences?

Thanks for any info, MG35

 

[SJB358]

You will be fine with starting at the mins with CCI250 primers. That's pretty much all I use for the 270 WSM. You will be fine with the 06 also. Good luck, let us know how they do. Scotty

 

[MaineGuide35]

Thanks Scotty,
Just woundering which one had more snap?

 

[DrMike]

MaineGuide35,

Welcome to the forum, and welcome to the delightful practise of handloading. You will be fine using any magnum primer. Just remember to start low and work up to ensure that there are no pressure issues. Either the CCI250 or the WLRM primers will give good ignition of your powders. I wouldn't anticipate much pressure differential between the two primers you mention. In my own short magnums, I frequently use large rifle primers (F210, WLR, CCI200 and R9.5) with good success. They work fine because of the shorter powder column. The major exceptions to this rule would be when using ball powders or when hunting in cold weather. I've used ammunition that was built with CCI200 and WLR primers in temperatures down to -25 C without a misfire. What is critical is to ensure that you start low and work up whenever you change any component. I have observed significant pressure increases when a load was developed with F210 and a friend built a duplicate load save for substituting F215 primers. Best of luck.

 

[MaineGuide35]

Thanks Dr. Mike
I appreciate the feedback!