CCI-400 pierced primers?

[BoilerUP]

Yesterday I was shooting my Savage 12FV 223 (26" 9 twist barrel) trying to see if it will shoot the 75gr A-Max.

My loads were this:

Virgin Nosler brass
CCI-400
Varget (24.5 up to 25.2gr)
75gr A-Max
2.45-2.46" COAL

75-80°F
Clear/sunny
Ammo & rifle shaded under portable canopy

For the first time in the 4 years I've been reloading, I experienced pierced primers. There were no other signs of pressure - no flattened primers (even on the ones that pierced), no sticky bolt lift, no ejector swipe on brass, etc. Incidence of piercings increased as the loads got hotter.

I know the Varget loads I was trying are over book, but so was the OAL. Thankfully, 24.5-24.8gr showed the most accuracy and there were just 1-2 piercings at 24.8gr.

Did not have any further issues with CCI-400s piercing yesterday while running milder loads in either the Savage bolt gun or a 20" AR (24.0-24.2gr Varget with 75gr HPBT at 2.25-2.30" OAL).

I don't plan on going above 24.8gr again, but would CCI-450s make a difference?

 

[jagged77]

Re: CCI-400 pierced primers?

Are you jamming the bullet into the lands or runing close?

I've only ever had one pierced primer with CCI 400's on a known hot load, have used Remington BR primers with the same load and had several go on me.

Try different primers by all means but I'm pretty sure the answer will lie in either reducing your load or seating the bullets slightly back from the lands if you're running close. If you continue with this load wear safety specs!

 

[High Binder]

Re: CCI-400 pierced primers?

Try some CCI #41 (white box) should help.

 

[BoilerUP]

Re: CCI-400 pierced primers?

All loads were 0.005" (2.46) or 0.015" (2.45) jumps to the lands.

The 24.5gr/24.6" load produced the best accuracy (first four into 0.25" @ 100yd then I shanked the 5th opening it up to 0.62") and there were absolutely no primer issues with that charge.

I think I had one or two pierce on the 24.8gr test loads (out of 10) but I I think that's moving out of the accuracy node anyway.

 

[MitchAlsup]

Re: CCI-400 pierced primers?

You might want to examine the firing pin for a slight nick--anything other than a nicely rounder profile on the tip needs cleaned up.

A primer that has no squared off edges and still gets pierced might come from a thin or week lot of brass in the primers.

 

[gunsnjeeps]

Re: CCI-400 pierced primers?

The AMAX is longer than a 77 SMK or the 75 HPBT. This could be the difference in your pressure from the 75 HPBT that you've been shooting.

Several sources say the CCI400 is a thin primer.

You may need to use a thicker primer with the AMAX since it will generate more pressure. The CCI 41 is thicker but I'm not sure how consistant it is. A lot of the long range shooter I know are using Wolf and Tula Magnums with good results. I've loaded CCI 450's for a .222 Remington load and they shot consistant.

Edit: After rereading your post, it sounds like you may not be seated as deep as I thought but it might bear looking into.

 

[Arkhangel5]

Re: CCI-400 pierced primers?

Boilerup,
I have a similar rifle(VLP) and it loves the A-max. Your load is similar to mine, I use H4895 though. I had the same issue with PMC primers. Switched CC BR-2's and no more pierced primers.

My OAL is 2.48, 10-off in my rifle. MV is over 3k w/excellent accuracy. This was with LC cases, they would last 3 firings.

I would try a harder cupped primer.

SY

 

[cascade tactical]

Re: CCI-400 pierced primers?

you might need to use CCI 450's or 41's. The 400 primers are thinner than the other two. These should solve the pierced primer problem, but beward of pushing the max. vel.

 

[BoilerUP]

Re: CCI-400 pierced primers?

Ran 50 rounds through the rifle today loaded with CCI-450s...not a single primer issue.

 

[George63]

Re: CCI-400 pierced primers?

I also had an issue with a mildly hot load and cci 400, I went back to some rem 7 1/2 with no more issues

 

[josephberry]

Re: CCI-400 pierced primers?

Both my 6.5x47, and my 6x47 are piercing cci 400s. Think I'm gonna switch over to the 450s.