Thoughts on 2x fired brass performance

[Wyo7200]

Wondering out loud, and someday I may test it though I think the variables of this thought has been tested independently in one way or another.

Conventional wisdom is once fired brass (same rifle) needs a minor bump in powder to achieve the same, or better accuracy. Something like the energy is needed to expand the brass on the first firing or something.

In QL, we use fired brass for accurate estimates, regardless if virgin, once fired or 20 firings.

It's known (maybe?) that the carbon and copper left over from the first firing produces a lube of some sort in the case neck...

Difference in neck tension (example-ball expander vs mandrel) can increase or decrease velocity- same influence as using lube for seating the bullet, or cleaned brass from ssm or sonic cleaning. (6mmbr has a topic on this)

Is the once fired case needing more powder (or seated deeper) due to the first firing's lube, and not because of the case capacity changed/ case is formed to the chamber?

I'm trying to lower the es I've been getting and I feel like it's in the neck tension/ssm cleaning. Conventional methods of walnut and corn, conventional load work up after the first firing. If I ssm tumble the brass after the first firing and not change anything else, the charge could in theory stay the same. If I use a little dry neck lube for sizing, I may have to adjust seating depth to regain the little bit of pressure loss.

What has me wondering about this is my 22-250 and .260... Maybe others. Seated straight from ssm tumbling, the 22-250 is 40 fps faster than if I pulled a case, and re-seated it, without changing anything else.

I don't have tumbler, so hopefully I can get some confirmations with dry neck lube.

 

[ElmerThud]

Brass prep is everything and there's no doubt in my mind, fired and re-sized brass performs better than new brass.
However, I no longer neck size brass & haven't for a few years now. I found full length resizing to fired case headspace dimension produces much more consistent results. Those results are further enhanced if you complete your loaded rounds using a Lee Factory Crimp die.
The die evens out neck tension variables and the nett result is more consistent pressures and closer MV & ES.

 

[greenheadcaller]

Wyo7200, I too prefer and absolutely promote the benefits of fired brass. fwiw, I don't think its your ssm cleaning.

I deprime and clean in a wet ss media tumbler prior to sizing also, so all my "carbon lube" gets removed each time. I then anneal, lube (lanolin based DIY lube), and size. Then they get a quick run in super small diameter 20/40 grit (won't plug flash holes) corn cob to remove lube and they get loaded.

Now to my suggestion for you. (The nice thing about this board is the number of great reloaders who can share opinions, even when we don't agree, attempting to learn something.) So my strong suggestion is to absolutely avoid crimping, and concentrate on consistent annealing (prior to every reload) using tempilaq if you are concerned about maximizing consistent neck tension.

Also...you mentioned you are using (or thinking about using) a hand applied dry neck lube for sizing. Are you then tumbling to remove it (or planning to)? If not, this could be part of it... if you are lubing by hand and not removing you may get inconsistent residual dry lube inside the necks.

Everything is relative.....and it kind of depends how your ES's are. If they are really wide, I would chase powder drop and overall case and case prep consistency and headspace consistency before necks. If they are generally already pretty darn good and you are chasing perfection ... then I would chase consistent neck sizing and annealing (long before I would let a crimp die touch my precious brass ---humor intended not offense --- smile)

Maybe more to the heart of what you were discussing ..... I never use new brass/always use formed brass to do load work ups .... to avoid the inconsistencies between new (first time) and once (or twice etc) fired altogether.

hope this helps

(only thing better than x fired brass is x+1 fired brass, etc, etc, etc) :grin:

 

[greenheadcaller]

Brass prep is everything and there's no doubt in my mind, fired and re-sized brass performs better than new brass.
However, I no longer neck size brass & haven't for a few years now. I found full length resizing to fired case headspace dimension produces much more consistent results. Those results are further enhanced if you complete your loaded rounds using a Lee Factory Crimp die.
The die evens out neck tension variables and the nett result is more consistent pressures and closer MV & ES.

ElmerThud ..while we may have different opinions on crimps ... I could not agree more with you about the importance of consistent and repeatable headspace measurements on sized brass, each time, time after time, tailored to the rifle. We may get there different ways, but agree with you it is important to achieve this.

 

[ElmerThud]

Brass prep is everything and there's no doubt in my mind, fired and re-sized brass performs better than new brass.
However, I no longer neck size brass & haven't for a few years now. I found full length resizing to fired case headspace dimension produces much more consistent results. Those results are further enhanced if you complete your loaded rounds using a Lee Factory Crimp die.
The die evens out neck tension variables and the nett result is more consistent pressures and closer MV & ES.

ElmerThud ..while we may have different opinions on crimps ... I could not agree more with you about the importance of consistent and repeatable headspace measurements on sized brass, each time, time after time, tailored to the rifle. We may get there different ways, but agree with you it is important to achieve this.

There you have it Greenheadcaller, diff'rent strokes for diff'rent folks. Like you, I do all I can to preserve my fired brass and for my use I do so pretty well.
As to the Lee FCD, the results I achieve utilising this method of 'equalising' neck tension, I find works very well, but prepping brass properly and as near exactly to the best fired case dimension certainly plays a significant part in achieving the most consistent time after time accuracy.
My view FWIW is that the OP shouldn't rule out the FCD, but no doubt he'll either try it and achieve successful outcome...or he won't. It's available as an option though.
Cheers, ET

 

[kraky1]

Fwiw... I've never had once fired brass make less velocity with the same charge as when virgin as a matter of fact usually it's the opposite usually my speed goes up 20 to 40 FPS.
One of the theories promoted to the internet is that on the virgin firing energy is lost to expand the brass.... I don't really know... I just know what I usually see on the Chrono.

 

[Wyo7200]

Cool. Very cool. Thanks for input. I'll re-read tomorrow as well.

Thanks guys- greatly appreciated.

 

[misser]

i am of the opinion that annealing is far more important than it being pretty. shoot it anneal it .repeat

 

[Joec7651]

This one has my curiosity. Very interesting observations.

 

[Blkram]

All a good discussion, and relevant for achieving the utmost accuracy for target shooting.

Keep in mind the need for reliable ammunition for in the field for hunting...especially of for dangerous game, whether it be those in Africa, or those that can bite back here in North America. This requires ammunition loaded in new cases, to ensure that everything holds together well for those cartridges being fired, and those still in the magazine.
A recent article in a hunting magazine relates the experiences of hunters who shot a brown bear, where the spent primer fell out of the fired case ( loosened primer pocket of reloaded cases used for hunting ammunition), jamming the action of the rifle. Their only recourse was to run from the wounded bear that was coming after them. The bear was eventually dispatched at close range with a handgun because of the now useless rifle. Good thing they had a back up!
They now promise to never hunt with ammunition using fired cases!

 

[Dr. Vette]

That sounds to me more like poor reloading practice by not checking their primer pocket sizes, or not paying attention to the pressure needed to prime them. One can find anecdotal evidence for almost anything in life.

I clean with stainless, anneal, then lube with Imperial and size, usually body die and then neck.
The necks are lubed with Imperial dry powder before I throw the powder and seat the bullet.
This generally results in low ES/SD; it definitely did yesterday.