Best burn rate for 55 grain, .223.

[Unclenick]

Originally Posted by dahermit

I remember people posting on here that CCI only makes one primer despite their "magnum" marking.

I think you've misremembered which ones are the same. CCI uses the same primer as their #350 small pistol magnum primer and their #400 small rifle standard primer, just packaged in different boxes. But their #450 small rifle magnum primer is hotter. Their #41 military sensitivity level primer has the same cup and priming formulation and quantity as the #450, but the anvil has wider angle legs to lower the sensitivity to the military spec for floating firing pin AR's. Federal also makes a military sensitivity primer, the GM205MAR, but it is not magnum like the #41, rather being the same as their 205M small rifle match primer except the cup is thicker, which is Federal's method of getting down to military sensitivity for floating firing pins.

I think you'll be pretty happy with the H322. It'll still be good economy for your stated purpose and I find it does well for accuracy in the 788. If you have a chronograph, use that to decide which primer gives you the lowest velocity spread with it.

[dahermit]

Originally Posted by Unclenick

I think you've misremembered which ones are the same. CCI uses the same primer as their #350 small pistol magnum primer and their #400 small rifle standard primer, just packaged in different boxes. But their #450 small rifle magnum primer is hotter. Their #41 military sensitivity level primer has the same cup and priming formulation and quantity as the #450, but the anvil has wider angle legs to lower the sensitivity to the military spec for floating firing pin AR's. Federal also makes a military sensitivity primer, the GM205MAR, but it is not magnum like the #41, rather being the same as their 205M small rifle match primer except the cup is thicker, which is Federal's method of getting down to military sensitivity for floating firing pins.

I think you'll be pretty happy with the H322. It'll still be good economy for your stated purpose and I find it does well for accuracy in the 788. If you have a chronograph, use that to decide which primer gives you the lowest velocity spread with it.

For what it is worth, the gifted primers I have are CCI 450's...so old they are also marked: "Cascade Cartridge Company" (two "bricks" of them). Also, one brick of No. 400's, (in a very old Green, Grey and Black box) and about five 100 count boxes of more current CCI BR-4 Benchrest primers...a little more load development than I had hoped for but "free" is always good to get.

[Unclenick]

All the CCI magnum primers made before 1989 are formulated differently from the current ones. In 1989 they added metal and barium compounds to throw hotter sparks for the St. Marks spherical propellants (Winchester Ball powders and Hodgdon's sphericals). Also, in, IIRC, 1992 they revamped the CCI line to eliminate burrs on the edges of the primer cups. Those burrs made the pre-'92 CCI primers harder to seat. I've still got a few boxes from back then because when I got my Dillon Square Deal press it couldn't seat the old CCIs consistently and I had to set them aside and go to Federal or Winchester or Remington to avoid high primers coming out of it.

Anyway, whatever load you end up with, if you switch to modern CCI #450s or to its less-sensitive twin, the CCI #41, be prepared to drop the load 5% and work back up.

[dahermit]

Originally Posted by Unclenick

All the CCI magnum primers made before 1989 are formulated differently from the current ones. In 1989 they added metal and barium compounds to throw hotter sparks for the St. Marks spherical propellants (Winchester Ball powders and Hodgdon's sphericals). Also, in, IIRC, 1992 they revamped the CCI line to eliminate burrs on the edges of the primer cups. Those burrs made the pre-'92 CCI primers harder to seat. I've still got a few boxes from back then because when I got my Dillon Square Deal press it couldn't seat the old CCIs consistently and I had to set them aside and go to Federal or Winchester or Remington to avoid high primers coming out of it.

Anyway, whatever load you end up with, if you switch to modern CCI #450s or to its less-sensitive twin, the CCI #41, be prepared to drop the load 5% and work back up.

More than likely, I will find some mild load, and not work-up higher at all. I have never been one for hot handloads...my practice has always been to start with the suggested starting load and work-up in small powder increase increments until I find an accurate load and then quit there regardless as to how mild the load is.

I have ordered factory second 55 grain soft points for shooting for fun, nothing serious...but soft points in the unlikely event (they only have shown-up on the trail cam at night) of seeing one of the coyotes that killed our pet Emdon gander...the S.O.B.'s.

Although I have a Dillon 550b, I load rifle rounds on an old RCBS Jr. and prime using an old Lee hand primer...with the round priming magazine...not the newish square one. I like the feel I get with the Lee.