Sizing consistency after annealing

[Ekupp]

My primary goal in annealing is to get consistent full length sizing. What I have noticed with certain sets of brass is that after annealing 70% of cases will be +/- .0005" of my target. 15% will be stubborn and not size and 15% will under size by .002-.004.

As an experiment I kept annealing the stubborn pieces for .1s longer till I got them to the proper size.

So, am I not annealing long enough or am I annealing too long and starting to get 15% that are too relaxed with the stubborn ones just needing to get adjusted to the baseline of the batch?

 

[Baker Alvin]

tagging in

 

[PddPdd]

Were they all fired in the same gun/chamber prior to re-sizing?

 

[Rosebud]

Need more info!

 

[parshal]

I've seen this with annealed brass. I see it more with many times fired (5-6x) in my 6.5 PRC Lapua. Some will just be harder to size. I even tried annealing those a little more (like 4-5 numbers higher on the AMP) and still the same. I haven't seen it with my 6.5 Creed Lapua brass.

 

[Ekupp]

Were they all fired in the same gun/chamber prior to re-sizing?

Yes all same chamber

 

[Ekupp]

I've seen this with annealed brass. I see it more with many times fired (5-6x) in my 6.5 PRC Lapua. Some will just be harder to size. I even tried annealing those a little more (like 4-5 numbers higher on the AMP) and still the same. I haven't seen it with my 6.5 Creed Lapua brass.

Do you think the harder to size ones were fired at one point at max/over pressure while doing load development?

 

[PddPdd]

Ekupp, Perhaps the brass is not being annealed after the same number of firings?

 

[parshal]

Mine were certainly the same number of firings and none of that brass had ever been shot to pressure. I've been running that gun slow.

Interestingly, I found internal doughnuts on that brass after five shots, too.

 

[victor3ranger]

Hmmm this has my attention

 

[PddPdd]

Mine were certainly the same number of firings and none of that brass had ever been shot to pressure. I've been running that gun slow.

Interestingly, I found internal doughnuts on that brass after five shots, too.

Solutions for doughnuts that I'm aware of 1) reaming neck ID, 2) Mandrel sizing of neck ID along with neck turning.

 

[parshal]

Mandrel does absolutely nothing. That's part of my normal reloading routine. I cut them out with a reamer.

 

[PddPdd]

My primary goal in annealing is to get consistent full length sizing. What I have noticed with certain sets of brass is that after annealing 70% of cases will be +/- .0005" of my target. 15% will be stubborn and not size and 15% will under size by .002-.004.

As an experiment I kept annealing the stubborn pieces for .1s longer till I got them to the proper size.

So, am I not annealing long enough or am I annealing too long and starting to get 15% that are too relaxed with the stubborn ones just needing to get adjusted to the baseline of the batch?

Just to clarify your "target", are you measuring neck ID, case overall length, headspace (shoulder bump), or something else after annealing and re-sizing?

 

[DoneNOut]

My primary goal in annealing is to get consistent full length sizing. What I have noticed with certain sets of brass is that after annealing 70% of cases will be +/- .0005" of my target. 15% will be stubborn and not size and 15% will under size by .002-.004.

As an experiment I kept annealing the stubborn pieces for .1s longer till I got them to the proper size.

So, am I not annealing long enough or am I annealing too long and starting to get 15% that are too relaxed with the stubborn ones just needing to get adjusted to the baseline of the batch?

This is what a lot of us see. You don't need to anneal brass longer. In a group of brass, some are just stubborn. You bump them shoulders .002 from fired size and the ones that don't go along with the program, you save for the last and screw your sizing die in a bit and size them the same too. This happens to all of us.