Winchester and CCI Primers comparison

[The Bushmaster]

Weapon fired 10 times. Bore punched with jag and patch. Test string was 5 rounds CCI-550 primed first. Bore punched with jag and patch and 5 rounds with WSPM primers. Not that it would make that much of a difference. But this has been my habit for years. Barrel started out cool for each string...

 

[alfack]

Ok. Just trying to play devils advocate here.

How do you know when you are at the maximum load?

There are the obvious signs, like flattened primers etc.. But what difference does it make if it was the primer that caused your load to be at that level, or the charge of powder? If I am seeing flattened primers, my first thought is not going to be "I better switch to some cooler primers." I don't know anyone that loads to the absolute maximum they can get away with, as often that is not the most accurate load. So, if you normally load mid-range rounds like me, I would think you would be absolutely safe using any brand of primer interchangeably.

Them's my thoughts. I could be wrong.

 

[freakshow10mm]

That's why you test one variable at a time.

By testing in an Enfield converted to 45 ACP, the primer falls out at 34,000 psi and the catastrophic case failure occurs at 41,000 psi. Brass was Starline.

 

[Mags]

Not necessarily a hard primer. It could have been set a little high. His firing pin seated it, your's set it off. I've found that to be the normal culprit when a primer goes off on the second strike.

Whatever it was I don't want to bet my life on it. I would hate to have to recreate the experience in a SD situation.

 

[The Bushmaster]

Alfack...Flattened primers are not a sign of over pressure. The firing pin pushes the case forward in the chamber. The primer fires and backs out a bit. The case is slammed back against the bolt face reseating the primer and flattening it. Granted...The hotter the load the flatter the primer, but it is not a sign of over pressure. Unless it is cratered, punctured or shows soot around the primer.

As far as using primers to set chamber pressure. I have a load for my S&W mod 19 that when using WSPM primers the fired cases are hard to eject. Switching to CCI-550 primers they eject smoothly. That will make a difference. And you are right. If you are loading mid range loads the primer has little effect as far as over pressure is concerned, but it could be a facter in accuracy...

 

[catspaw]

All reading of flat primers aside, I used to use WLR's with H4895 in my Palma rifle. After three loadings of Winchester brass, the primer pockets were loose. I mic'd the WLR's at .2100, while the Federal 210M's I was using with a Varget load mic'd .2104. My Winchester brass holds onto the Federal primers for eight loadings before new primers seat too easily. This with 47.0 grs. of Varget and a 155 SMK.

 

[The Bushmaster]

Catspaw...You might try CCI-200. They tend to be a bit larger or harder. Not sure which, but they seat a bit harder then WLR or Federals.

I use predominately CCI, but I seem to be out of them at present and have WLR in stock instead or I'd measure one for you...