AMP Annealer and mixed brass???

[LawshrinkMD]

I am wondering if anyone has been using a minimum "safe" code, so they could process mixed brass, similar to how people use flame based annealing systems set off Tempilaq. I understand that the ideal use of the AMP is to consistently process higher quality brass to enhance both accuracy as well as case life, but I wonder if there is a code for the thinnest brass which would be safe for mixed 223, or at least mixed date LC brass, and hopefully provide some benefit.

Since people have been annealing brass the "old fashioned way" with flames for many years with some benefit, I imagine there is a setting which, even if not optimal for any one headstamp, would provide some of the benefits of annealing. I have a 1-2k of mixed LC brass, and dread the idea of trying to separate it out by year. I recall reading somewhere that LC uses multiple manufacturing lines or lots, so it wouldn't be as uniform as Lapua or a premium brand anyway, even if sorted by year.

I plan on switching over to all Starline or another more premium manufacturer at some point, but for now I have lots of 1x or 2x I want to continue using, and my new AMP and AMP mate is just sitting there...

 

[robert8904]

I was tempted to try the same thing but decided not to. If it's to be used in autoloaders, I definitely don't advise it. You could analyze some cases, including samples from several years and weights. If the aztec codes are within a range of not more than 6 points, pick an average code and have at it. In my experience, annealing a 223 case 4-5 points higher than the right code will soften the necks quite a bit. 4 points less gave brass that looked hardly annealed at all, although that's just the appearance. A softened case neck from over annealing is not a big deal in a bolt action, it could easily be a safety concern in a semi auto.

Its likely that the cases annealed from mixed brass in an AMP would vary more in headspace and neck "tension" than the not annealed brass you have.

 

[LawshrinkMD]

My PPU07 brass had a range from 132 to 138, and I had weighed 100 cases and entered it all into Excel to make a graph of the normal curve it produced. So lower quality brass can vary quite a bit, even with exact same headstamp... Alex suggested going with 136, although the average weight pieces gave a code of 135.

 

[LawshrinkMD]

Its likely that the cases annealed from mixed brass in an AMP would vary more in headspace and neck "tension" than the not annealed brass you have.

I'm curious, by this logic, any non AMP annealing would be more likely to have the opposite effect. I guess without doing an experiment and recording the results, there's no way to know.

 

[robert8904]

I'm curious, by this logic, any non AMP annealing would be more likely to have the opposite effect. I guess without doing an experiment and recording the results, there's no way to know.

I see your point. Automated flame annealing would, like the AMP, not differentiate between unlike cases. Manual flame annealing could allow annealing unlike cases if the operator was skilled.

 

[LawshrinkMD]

This is for practice ammo at 200 yds or less. I was hoping to keep my sizing die adjusted the same as well, since the annealed PPU appeared to be sized about 0.001"or so more than the non annealed, and that would be too much.

Even with mixed range brass, I have noticed expansion of group sizes (especially flyers from cracked necks) after 5-6 loads, and I was hoping to eliminate that as I transition to better brass and bullets. My shooting continues to evolve...

 

[boltfluter]

Personally I see no point in annealing mixed brass in the first place. If you insist, I would at least sort them by brand and go from there. Annealing them in lots.
Paul

 

[6BRA]

Since your shooting mixed brass, why are you worried about mixed annealed results. The brass has different neck thickness so they are going to shoot to different points of impact. If you want. mic the neck thickness and sort them that way.

Unless you are turning necks the best brass has different neck wall thickness. By .001 or more.

 

[LawshrinkMD]

I appreciate all the replies. People purchase Hornady 55 gr FMJs and load them in scrounged mixed brass on their progressive for a reason. I know what me and my rifle can accomplish at 200 yds with that combination. I hope to prolong the brass life and maintain the current accuracy with once fired, and not do anything that would make this worse. I have plans for getting into neck turning and sorting by weight and neck wall thickness, but I'm not at that point in my shooting yet.

 

[avidflyer]

My PPU07 brass had a range from 132 to 138, and I had weighed 100 cases and entered it all into Excel to make a graph of the normal curve it produced. So lower quality brass can vary quite a bit, even with exact same headstamp... Alex suggested going with 136, although the average weight pieces gave a code of 135.

Had Lapua 308 srp brass give me a wide range like you got....emailed the guys at AMP (which have always been helpful and responsive) said it should be a lot tighter and basically thats it.....I did the same

 

[LawshrinkMD]

Had Lapua 308 srp brass give me a wide range like you got....emailed the guys at AMP (which have always been helpful and responsive) said it should be a lot tighter and basically thats it.....I did the same

Weird, and you would expect Lapua to be so much higher quality and have more uniform numbers than crappy Prvi Partizan!

I plan on weighing a large batch of my LC brass and keeping track of weights and neck thickness by year, and see if the spread is close enough that I can just process them all on the same number.