6.5 Creedmoor Brass primer size

[BowWow]

There seems to be some debate about the 6.5 Creedmoor primer size and how it effects the rounds accuracy. Allegedly the small primer brass is more accurate than the larger primer brass...... Is there any truth to this from anyone's experience? I can't imagine (given the fact there is nothing wrong with the primers) it would make any difference.

 

[GymB]

Have read the same, don’t recall if there was an explanation.

 

[Downeast]

A friend of mine called one of the leading bullet/ammo manufacturers last week to enquirer about a specific load and ended up talking to one of their main ballisticians. When asked about small vs large primer size in both the 6.5 and the 6mm Creed they guy told him to use standard primers' After extensive testing they found no advantage to using small primers. In other words, it's a gimmick.

 

[jmccracken1214]

Better ignition and burn with small.

I run small cci 450 in all mine. I’m able to get higher speeds with no pressure compared to large primers

 

[jmccracken1214]

A friend of mine called one of the leading bullet/ammo manufacturers last week to enquirer about a specific load and ended up talking to one of their main ballisticians. When asked about small vs large primer size in both the 6.5 and the 6mm Creed they guy told him to use standard primers since they could find no advantage to using small primers. In other words, it's a gimmick.

Same load I’m using in either of my rifles with large primers, I get bad pressure signs. Craters like crazy. Small primer.... not a issue.

I’m not sure the exact difference but there is one

 

[Downeast]

Just passing on the gossip.

 

[jmccracken1214]

Just passing on the gossip.

I hear ya, I went through the same stuff, reading the same things where some swear by it and some say no difference but I’m running almost 2 gr more powder with this small magnum primer than the large match, and it’s 1gr more than the large magnum could handle.

I’ve had large primer rounds shoot good for accuracy, but I’ve found accurate loads easier with small primers. There’s a good chance a lot of this is just luck and what my rifles like. But seeing the ability to crank out more speed with no pressure, I switched to small lol

 

[jmccracken1214]

Also you will get more life out of your brass with small primer pockets. The large primer pocket end up wearing out and becoming too big sooner than the small