Just finished Annealing and this happened...

[CDuklet]

I've been shooting Lapua brass in my 6.5 Creedmoor for some time now with good results. I've reloaded my batch of brass between 5-7 times and felt that I needed to anneal it. Using an Anealeze I annealed the batch, did a re-size to push the shoulder back .002, cleaned the primer pockets and trimmed the cases basically giving the batch a full day at the spa.

So I also wanted to redo my load testing around my usual 41.7 grains of H4350 because of these changes and during my last reloading I don't think this load was doing as well as when I first started using it. My groups started to open up to .75" inches and a few out to 1" from a fairly solid .5".

So I've shot about 40 rounds with loads from 41.5 grains to 42.1 grains and I got two rounds where it looks like the firing punctured the primer(CCI). See attached picture.

I was able to push out one of the primers and I found flow back toward the primer around the primer pocket hole. You can also see by the picture that my primers are flattening more than I'd like. This is unusual considering how my first rounds from the load have worked up until now.

While shooting I noticed nothing wrong, outside of that my groups were not great. I was unable to fined this missing disk part of the primer. I took the bolt apart and found nothing wrong. The gun was cleaned prior to shooting. I have about 1500-1800 rounds in this barrel.

So my question is did I do the annealing wrong? Where is this pressure coming from? Be honest. I'm semi-new to reloading, certainly no expert.

Thanks in advance,

Duke

 

[ChrisA]

Any chance of a carbon ring in the leade area of chamber?

Chris

 

[Lefty Trigger]

After annealing the brass inside neck lube is an important thing or the bullets stick easily. I notice extra drag on my resizing die expander ball as well. The heat from annealing cooks away all the lube in the neck and the brass is really dry. Try pulling a bullet and see if its all scared up,.. could have run your pressure up to the limit with tight bullets?

 

[PopCharlie]

I just experienced something like this in my .223 bolt gun. Flat primers and catering of the firing pin depression. It was on some cases and not others. Al in all I had 51 cases like this. They were out of the initial 200 cases I bought new. They have had 6 firings of a max load and 7 firings of a lighter load. Annealed after each firing on an AMP annealer. Turns out, the primer pockets were loose. I used a go no-go tool to test them. They weren't big enough to allow the no-go side to go in, but the go side had a lot of wiggle compared to a new case. After 13 firings, I thought it was time to toss the cases.
PopCharlie

 

[CDuklet]

After annealing the brass inside neck lube is an important thing or the bullets stick easily. I notice extra drag on my resizing die expander ball as well. The heat from annealing cooks away all the lube in the neck and the brass is really dry. Try pulling a bullet and see if its all scared up,.. could have run your pressure up to the limit with tight bullets?

What neck lube do you recommend? Also, why did I not see this on my other rounds I've annealed?

 

[CDuklet]

Any chance of a carbon ring in the leade area of chamber?

Chris

I'll look, but I did clean the rifle and the chamber.

 

[Texas10]

Probably had nothing to do with your annealing, more to do with the hotter weather of summer. Your load is a bit on the warm side, so a carbon buildup in the throat is a possible contributor along with hotter weather than when you developed the load. Drop your load a few tenths of a grain. Are you shooting heavier than 140 gr bullets with that charge?

Also, are you trimming necks to length after you anneal and size? If not, that could explain it right there.

My best load using an X-caliber 8 twist and 140 SMK is 40.9 of H4350, but that's with MY lot of powder, not yours. The 142's like a bit more powder, 41.5, and I'm jumping .020.

Another possibility is that if you're shooting a Savage, your bolt head could use a bush to lessen clearance around the firing pin. BTW: that's called primer blanking and @Grimstod can help you out there. He'll bush the bolt head and put a lift kit in if you want.

Switching to large primer brass will help too.

If you don't already have one, invest a couple dollars in a borescope camera. Teslong has them for $60. Best money you'll ever spend.

 

[CDuklet]

After annealing the brass inside neck lube is an important thing or the bullets stick easily. I notice extra drag on my resizing die expander ball as well. The heat from annealing cooks away all the lube in the neck and the brass is really dry. Try pulling a bullet and see if its all scared up,.. could have run your pressure up to the limit with tight bullets?

But I was able to re-size easily. Would I not have seen this during re-sizing? I did use one shot lube during the process.

Bigger question: How do I know I've done the annealing correctly?

 

[DngBat7]

Bigger question: How do I know I've done the annealing correctly?

There is a lot a lot a lot of very good past threads on that.

 

[46and2]

Annealing leaves a sticky "tarnish" on the necks. I tumble with corn cob after annealing to get rid of some of it and I use Imperial dry lube ( graphite) right before seating bullets.

You could also run a bronze bore brush in the necks also.

 

[CDuklet]

I'm shooting a 142 gr Noz. I did trim after annealing and resizing. I'm shooting a Rem 700 action with a Hart barrel. I have changed to a brand new lot of powder...

 

[CDuklet]

Will enough bronze transfer from the brush to the inside of the case to make a difference?

 

[CDuklet]

Any chance of a carbon ring in the leade area of chamber?

Chris

What is the best cleaning solution for carbon build up like this?

 

[jpx2rk]

What is the best cleaning solution for carbon build up like this?

Topic has been discussed quite extensively, just search for carbon ring and you'll have several days worth of reading.

 

[rwj]

... I have changed to a brand new lot of powder...

A new powder lot could well be a large contributor! Were the rounds in the picture the first ones fired with powder from the new lot?

 

[CDuklet]

A new powder lot could well be a large contributor! Were the rounds in the picture the first ones fired with powder from the new lot?

Yes

 

[dogdude]

Powder lot#'s are like ladies...some like ya some Don't, just work your way around the ones that Don't with a Chronograph.

 

[Straightshooter1]

I'm shooting a 142 gr Noz. I did trim after annealing and resizing. I'm shooting a Rem 700 action with a Hart barrel. I have changed to a brand new lot of powder...

A lot of good suggestions as to what to look at for the cause of the problem. I doubt that a change in your lot of powder is an issue for the primer blanking as your load of 41.7 gr of H4350 may be a little hot depending on how long you're loading them too (QL app shows well below the SAAMI max pressure of 63,000 psi), but it could be the causes for the change in your group sizes. Did you use a new lot of primers, as the particular primer lot could be part of the problem?

I'd certainly check for carbon ring, as that is so often the cause of a rather sudden increase in pressure where you see pressure signs.

I use an Annealeez also and will be sure to use a lube for seating since annealing leaves that rough/sticky residue on the necks. I also doubt that's contributing much to any increase in pressure, but certainly can affect group size. That's been my experience, anyway.

 

[rardoin]

A new powder lot could well be a large contributor!

H4350 in particular has shown wide variation between in charges needed for a particular velocity. I agree that I would start there.

 

[mikecr]

How much of the case was annealed?
Did you measure your shoulder bump with each round?