Home Forums Reloading Big Game Rifles Small primer pocket vs regular primer in 6.5 Creed

Tried to do a search, no luck. Which is better in a 6.5 Creed, small primer pocket or regular size primer pocket. Thanks

I prefer large rifle primers

I tested both and dint see any difference

I use large rifle but I need everything to work at -20* occasionally

You will when it gets cold. I use large rifle primers and don't have to worry about schidt like that with them. Loads shoot just fine and no hangfires to worry about. To each his own.

I’ve used 6.5x47 down in the sub-zero temps without any issues. They don’t make a large primer version of that case. Try it and see what happens. I bet in all but the most extreme circumstances nobody sees a difference.

cci 450's

I use large primers and I have never had a single problem or misfire.

I recommend large primers!

I also prefer large rifle primers for my 6.5 Creedmoor.

I tried the SRP route in 22-250 AI with H414 and URBR brass years ago. It did not work out well in super cold weather. Not only did it cost me a few coyotes the SRP trial did not reveal any improvement in accuracy in a very accurate rifle.

Your mileage my vary.

My understanding of using a small primer in a cartridge previously designed for large primer is to withstand more pressure, ie. a little hotter load than normal, to gain velocity. IIRC it started as a fad with the 308win in match ammo.

The theory as as I've heard is the case head web has more meat around the primer with small vs large, less square miles of primer surface for the pressure to push back on, and thus less prone to blow a primer out with a hot load.

Unless that velocity gain is your goal you probably won't see any improvement in anything that large primer cases will give. I've not paid any more attention to it than that, I've never tried it, and I have no idea about load data.

The increased pressure tolerance is a nice side benefit in the .308, but the original intent in that chambering was to provide a more consistent ignition and smaller velocity spreads in the ammunition used by the United States Palma Team in the Long Range World Championships held every 4 years. My understanding is Tom Whitaker lobbied Lapua to produce the first batch for the team and it became widely available thereafter.

Thanks Mike, for the clarification 👍

No problem, the added strength benefit is very real in my experience as related to case life. I expect at least 15 firings with high pressure loads in my rifles. Large primer brass is done within 10.

I recently started using SRP Peterson brass in my target 308 win. There has not been any degradation in accuracy. Increased case life plus component availablity are the drivers. In case of shortage it's good to have options.

I've tested small and large primers, and they burn alot hotter than some large ones. Regardless of how long it's been since the testing..... Rem 7-1/2 burns hotter than a WLR. CCI 450 is up top for most.

https://forum.accurateshooter.com/threads/best-small-rifle-primers-for-hotter-loads.4057519/

What primers were you using?

Bought some Small Primer 6.5CM Brass when primers were really hard to find. With CCI400's I would get pierced primers on about every 4th shot. Switched to CCI450's and never had another. Both small and large rifle primed load shot the same for me. I did not test in very cold conditions which may favor the large rifle primers.