CCI #41 Primers

[Larryswn]

Small rifle primers
#41......................................Mil. Spec. primer, thick cup, magnum primer charge, angle of anvil change.
BR4.....................................thick cup, standard anvil and standard priming mix held to a tighter tolerance.

The #41 is not at all the same as the CCI 450 Magnum primer. Anyone promoting that line of thought should give CCI a call or email them. They have always been happy to share information.

I did a brief comparison test last summer using four flavors of CCI primers and recording velocities. The brass was all identical, the cases trimmed identical and the same bullets and weighed powder charges.

Please keep in mind I was more focused on getting velocities than hitting the targets so the twn shot groups suffered a little. All shots were with a bolt gun having a 1:12 twist barrel.

I would treat the CCI #41 primers like any other primer starting low and working up a load. Interesting that for a given load the Magnum primers did not always have the fastest velocities.

Ron

Good info I took some samples of all charges from min to max to the range yesterday. Got up to the max and primers looked good so I think I'm good to go on pressure

 

[sirgilligan]

You won't find 5.56NATO load data anywhere. Data used is .223 Rem.

That is not the case anymore.
http://www.ramshot.com/wp-content/uploads/2010/09/WesternLoadGuide1-2016_Web-1.pdf

POWDER : RAMSHOT TAC

5.56 X 45MM NATO
CIP COMMERCIAL AND NATO/MIL SPECIFICATION (62,350 PSI)
Barrel: 24” ¦ Twist: 1-7” ¦ Primer: WIN WSR ¦ Bullet Diameter: 0.224”
Case: WIN ¦ Max Case Length: 1.760” ¦ Trim Length: 1.750”

68 HDY BTHP-M 23.4 2,851 26.0 3,133 61,995 2.250


-------------------------------------------------------------------------------------

223 REMINGTON
55000 PSI -- STANDARD SAAMI COMMERCIAL SPECIFICATIONS
Barrel: 24” ¦ Twist: 1-12” ¦ Primer: WSR ¦ Bullet Diameter: 0.224”
Case: WIN ¦ Max Case Length: 1.760” ¦ Trim Length: 1.750”

68 HDY BTHP-M 22.0 2,699 24.4 2,964 54,191 2.250

-------------------------------------------------------------------------------------

The max load for .223 REM is 24.4, the max load for 5.56 NATO is 26.0.

So, there is load data specifically for 5.56. I think Hornady also now has specific load data for 5.56.

 

[MEHavey]

CIP COMMERCIAL AND NATO/MIL SPECIFICATION (62,350 PSI)
55000 PSI -- STANDARD SAAMI COMMERCIAL SPECIFICATIONS

Uuuuuuhh.... No.
See https://ballistictools.com/articles/5.56-vs-.223-myths-and-facts.php

 

[sirgilligan]

1. Uuuuuuhh.... No.

See https://ballistictools.com/articles/5.56-vs-.223-myths-and-facts.php

No on what? The max loads for the same bullet is very different.

                           5.56 Ammo.                    223 Ammo
5.56 Chamber    55,000 PSI                48,000-55,000 PSI
.223 Chamber    55,000-65,000 PSI         55,000 PSI
Table 1: Fired from the correct chamber, 5.56 and .223 are equivalent in pressure.

Notice that there are four things in play, two different chambers, and two different cartridges.

The cartridge mated with its chamber never produces over pressure.

Thus the two different load data from RamShot.

While the specified pressures of 5.56 and .223 are the same, the pressures are measured when they are fired from the correct chamber. 5.56 can indeed be "hotter" than .223, because the leade of the chamber is designed to allow "hotter" loads with lower pressures.

 

[MEHavey]

The issue was "hotter" pressures.
When handloading, the pressures are identical.

The cases/chambers, per se, are also identical
Only the 556 leade/throat angle is different :shallower/longer


.

 

[sirgilligan]

The issue was "hotter" pressures.
When handloading, the pressures are identical.

The cases/chambers, per se, are also identical
Only the 556 leade/throat angle is different :shallower/longer


.

Yes, therefore the chambers are not identical, but the brass itself is the same.
The 5.56 NATO cartridge can use more powder to reach max pressure in 5.56 chambers than a .223 REM cartridge, thus 5.56 NATO cartridges are a superset of .223 REM, or in other words, probably all .223 REM cartridges can be considered a 5.56 cartridge but not the other way around.

As the article clearly points out, 5.56 ammo may be hotter and therefor when fired from a .223 chamber the maximum recommended pressure for .223 is exceeded.

When hand-loading for 5.56 in a 5.56 chamber, then indeed the maximum pressure for 5.56 in a 5.56 chamber is the same as the maximum pressure for hand-loading .223 in a .223 chamber.

I hope no one thinks that a maximum hand-load for a 5.56 chamber will produce the same pressure in a .223 chamber.

 

[Larryswn]

Yes, therefore the chambers are not identical, but the brass itself is the same.
The 5.56 NATO cartridge can use more powder to reach max pressure in 5.56 chambers than a .223 REM cartridge, thus 5.56 NATO cartridges are a superset of .223 REM, or in other words, probably all .223 REM cartridges can be considered a 5.56 cartridge but not the other way around.

As the article clearly points out, 5.56 ammo may be hotter and therefor when fired from a .223 chamber the maximum recommended pressure for .223 is exceeded.

When hand-loading for 5.56 in a 5.56 chamber, then indeed the maximum pressure for 5.56 in a 5.56 chamber is the same as the maximum pressure for hand-loading .223 in a .223 chamber.

I hope no one thinks that a maximum hand-load for a 5.56 chamber will produce the same pressure in a .223 chamber.

Excellent post, now I get it.