Sizing well in advance of loading

[dboyles]

What are your thoughts on sizing days, weeks, or months before priming and loading cases? Does the brass change measurably over time, and if so, for better or worse? Wondering if anybody has experimented and has results to share. My hypothesis is that it's a good thing to size the brass and leave it for a little while to "settle." I've got nothing to back that up, though.

In my specific case I'm neck sizing (Lee Collet) and body/shoulder sizing in two separate operations on freshly-annealed Lapua .223. Necks are pretty consistent and unturned (.0132" +/- .0002"), and are sized down from ~.254" to .249".

 

[scissorhands]

I do all my resizing/case prep all together. I might resize 200 cases and just load what I need for a trip to the range or match. Once all 200 cases are fired, I start the resizing/case prep process all over again

 

[MNFinn]

I do all my resizing/case prep all together. I might resize 200 cases and just load what I need for a trip to the range or match. Once all 200 cases are fired, I start the resizing/case prep process all over again

that's what I do too. I like to keep track of the number of firings I get from my brass, so keeping the brass together is a must for me

 

[M-61]

I have some 222 Remington I loaded in the early 70's. I turned the necks as it a custom with a tight neck. Factory ammo will not chamber. For some unknown reason about 30 of these loaded rounds sat in a case, marked with the load, bullets and date I loaded them. Why I never shot them I have no idea as I surely used that rifle and still have it.
I opened the hidden box in the last year. I found that ( I think) the case necks shrunk to the point that just a quick glance clearly shows the depth in the necks to where the bullets are seated. It's very obvious.
You are asking about 'days,weeks,months not 4 decades time between loading but I found it interesting as something surely happened. I chose not to shoot them. There are no split necks which when you see what happened is sort of surprising.

 

[Immike]

M-61 you got me curious! How much different does the neck measure below the bullet?

 

[M-61]

M-61 you got me curious! How much different does the neck measure below the bullet?

I went and measured a few. The average 'bulge ' is almost .002......really not the number I expected to see as this is REALLY noticeable. It is hard to measure as it (or appears to be) a slight curve from the base of the bullet to the part of the neck below the bullet.
I would see if they chamber BUT I don't want have a stuck loaded cartridge in the rifle. It has a shell holder bolt face which grasps the brass far better ( and a much greater area) than a normal extractor but I can let them sit in there container and pull the bullets should I need them.

 

[jonbearman]

I dont see any reason not to size and prepare them in advance.I have done it for years and when I go through all of them,I start over and prep again.

 

[BoydAllen]

Here are a couple of experiments that you can do. Start with a number of cases from the same batch, that have been fired and sized a like number of times. Size a few, and set them aside for say, three weeks. At the end of that time, size the rest, and load them all, paying attention on the amount of force it takes to seat the bullets. This is more easily detected with an arbor press and suitable die.

The next thing that I suggest is that you expand a batch of cases for turning, and turn half of them, and then wait a week to turn the rest.

 

[jcampbellsmith]

I do all my resizing/case prep all together. I might resize 200 cases and just load what I need for a trip to the range or match. Once all 200 cases are fired, I start the resizing/case prep process all over again

that's what I do too. I like to keep track of the number of firings I get from my brass, so keeping the brass together is a must for me

I'm with both posters here. Regards JCS

 

[Martin52]

In my specific case I'm neck sizing (Lee Collet) and body/shoulder sizing in two separate operations on freshly-annealed Lapua .223. Necks are pretty consistent and unturned (.0132" +/- .0002"), and are sized down from ~.254" to .249".

The 2 stage process is good when there's not enough clear time to do the whole (FLS) reloading process close to a match. I like to have a few cases fully prepped and body sized (I use a FLS bushing die with bushing removed in order to leave the neck sizing until later). I do these well in advance, then just just before a match, I use a Lee Collet and reload. That way the neck tension is not going to vary, however it will if the necks are sized and then left for days or weeks before loading.

Martin

 

[M-61]

Here are a couple of experiments that you can do. Start with a number of cases from the same batch, that have been fired and sized a like number of times. Size a few, and set them aside for say, three weeks. At the end of that time, size the rest, and load them all, paying attention on the amount of force it takes to seat the bullets. This is more easily detected with an arbor press and suitable die.

The next thing that I suggest is that you expand a batch of cases for turning, and turn half of them, and then wait a week to turn the rest.

This is something I will try. Arbor press I have and as in the past this rifle loves Sierra 52 HPMK's...same bullets (meaning make and model as years ago), and Wilson dies. The only thing I do not have is Remington unturned brass...just Lapua. Three weeks I also have....another 40 years...not really, but I posted this as a point of interest in regards to the long time period and I was the one that turned them and loaded them and there was no third party involved so the actual history is definite not a guess. As I always have I handled the bullets, primers, and cases. I have never worried about touching them with my fingers...there is NO sign of corrosion (or growing hair) anywhere on the cartridges that is visible..... Just the bulge.

 

[Larryh128]

More than likely it's caused by the tension on the bullet. There is no reason for brass to move at all if there are no stresses on it. As loaded ammo sits, it will slightly increase the amount of tension on the bullet. I try to shoot my loaded ammo within a couple years BUT if you have loaded ammo that is many years old, simply seating the bullet another .010 deeper will "break" it loose.

 

[BoydAllen]

In past discussions of the bonding of a bullet in a case neck, during long term storage, that results in a popping sound when the bullet is seated a little deeper, this phenomenon has been referred to as cold welding. Whatever the cause, it happens. A friend takes a step in his reloading of ammunition that is likely to be stored some time before use that is designed to prevent this bonding. He applies a thin coating of Imperial sizing wax to each bullet, with his fingers, before seating it. I have not tried this, but he has been doing it for some time with success, so I thought that I would pass it on.

 

[dboyles]

The 2 stage process is good when there's not enough clear time to do the whole (FLS) reloading process close to a match. I like to have a few cases fully prepped and body sized (I use a FLS bushing die with bushing removed in order to leave the neck sizing until later). I do these well in advance, then just just before a match, I use a Lee Collet and reload. That way the neck tension is not going to vary, however it will if the necks are sized and then left for days or weeks before loading.

I've done this before too, but I'm not sure why... hence the reason for this thread. Why would you think that freshly-sized brass will be more consistent in neck tension than that which has been sized for, say, a week? Variation in spring-back? Let's assume in either case that the loaded rounds are going to be shot immediately.

 

[BoydAllen]

The problem lies in the reliance on assumption rather than doing a simple test. The fact is that if you do the experiment that I outlined you will observe a difference in the force it takes to seat bullets. And in the case of neck turning, the turning mandrel will fit tighter in case necks that were expanded several days before, as compared to those that were done right before they were turned. I have never done the experiment with a collet die, so until I do, I won't know if that method of sizing necks produces a different result. It may.

 

[dboyles]

Sure, if we size or expand a neck it will tend to "relax" over time, but once we take that into account and adjust accordingly to get the neck diameter that we want at the time of bullet seating, what are the effects of one method over the other? This is harder to test since you can't easily compare seating effort done now versus 2 weeks from now.

I'm not necessarily looking for a "this way is best" answer. Just wondering what others' thoughts and experiences are.

 

[BoydAllen]

Yes, you can. Do something to a case, and then wait two weeks to do the same thing to another case from the same batch, and then measure the effect on both right away (better if you do several of each). I have done it. It's easy. No speculation required.

 

[Benjerman08]

I did this same experiment last summer after a similar thread was posted. I believe Boyd talked about the experiment in that one also. He is spot on. I use a fairly light seat on my fclass cases. The ones that I sized and seated the same day had a lighter "feel" (seating) than the ones that sat a few weeks after being sized. Using the chrony for both test groups showed no noticeable effect on velocity or accuracy. After seating thousands of bullets you will definately get used to a certain "feel" on your seating. I really don't worry about it anymore. As long as you do everything the same each time.

 

[dboyles]

Yes, you can. Do something to a case, and then wait two weeks to do the same thing to another case from the same batch, and then measure the effect on both right away (better if you do several of each). I have done it. It's easy. No speculation required.

I was multitasking when I posted what you responded to and ended up confusing things. Let me ask in a different way: Is there likely to be a difference in neck tension between two identical cases, one sized a month before loading and one sized immediately before, if the dimensions are identical at the time of loading? If so, which would you think promotes better consistency?

 

[BoydAllen]

I don't know about consistency, and there may be more to it than diameter shows. As long as you don't mix them, I don't see a problem. When I have made comparisons it was using the same die or bushing, doing the same thing to both. Recently, a friend did some really good shooting with some loads that had been sitting around for a couple of months. It led me to speculate if there was some advantage to aging loads for a short period, in situations were they were going to be preloaded. Again, I don't know. Since most of my high accuracy loading is done at the range, I do virtually all of my sizing just before shooting, but on those occasions when I have sized cases some time before they were loaded, I have not mixed them in the same group with cases that were freshly sized, and had not had any bad results.