Prepping Brass In Advance

[bill123]

Is there any advantage to prepping brass right before priming, charging and seating bullets? For example, if I clean, resize, trim, etc. 500 cases and then wait to prime, charge & seat bullets as I need them, should I expect any precision or MV variation from the first batch to the last? I wonder if the neck tension or something else changes if you don't seat right away.

 

[MagnumManiac]

Is there any advantage to prepping brass right before priming, charging and seating bullets? For example, if I clean, resize, trim, etc. 500 cases and then wait to prime, charge & seat bullets as I need them, should I expect any precision or MV variation from the first batch to the last? I wonder if the neck tension or something else changes if you don't seat right away.

Having brass ready to load should pose no problem, having loaded rounds sitting around for a long time can and does pose a problem as brass has a tendency to 'cold weld' to bullets over time, changing the start pressure and max pressure.
I always prep my brass and store it in sealed snap lock bags.
I never trim new brass though, as it is unstable and will stretch at different rates until it has been fired a few times. Unless you are crimping, I do not find it necessary to trim and it has no bearing on accuracy, even at 1000yrds.

Cheers.
gun)

 

[Mikecr]

The resizing part is better done right before fully loading. Even if you remove the potential for cold welding, brass spring back continues (creeping) over time.
So capacity changes with FL sized cases, and potential neck tension changes. Even primers creep over time. All due to spring back trying to reach lowest energy level(releasing energy you added).

I know this isn't what many would want to do. But where you want the best ammo, you should do this. If you need 10 rounds for a hunt, load 10 rounds. Same for 20 for the range or 100 for a weekend match.

 

[bill123]

Thanks for the replies guys. Sounds like its time for a test. I'll report back in a while.

 

[hemiford]

What does this say about 20-yr old factory ammo ?

 

[climb-101]

i haven't seen any difference in prepping brass before hand or right before i use it. i would assume that all the spring back in the brass happens as soon as the brass is resized. i would be interested to see if someone has measured the size right after it was sized vs a month later vs a year later.

 

[woods]

It pays to pay attention to what Mikecr posts

I have noticed a little harder seating on cases that have been prepped and sitting for awhile

 

[AZShooter]

MikeCR,

How about some empirical evidence that loading up right before use makes a difference in performance? Any articles out there on this subject? Anyone ever do a comparison test?

I have a friend that shoots 1000 yds and he will load up his ammo a few days before the match. He uses the same brass over again with only enough for the sighters and the match. Never thought it was because he would get better results. I am willing to learn something new, but so far I am not convinced.

I am interesting in reading what the BR guys have discovered if it exists. IMO this level of detail doesn't matter when it comes to making handloads for hunters.

Personally I have loaded ammo that has sat for years that still shoots excellent groups and kills the animals I shoot at just fine.

 

[FEENIX]

MikeCR,

How about some empirical evidence that loading up right before use makes a difference in performance? Any articles out there on this subject? Anyone ever do a comparison test?

I have a friend that shoots 1000 yds and he will load up his ammo a few days before the match. He uses the same brass over again with only enough for the sighters and the match. Never thought it was because he would get better results. I am willing to learn something new, but so far I am not convinced.

I am interesting in reading what the BR guys have discovered if it exists. IMO this level of detail doesn't matter when it comes to making handloads for hunters.

Personally I have loaded ammo that has sat for years that still shoots excellent groups and kills the animals I shoot at just fine.

Ditto! I'm like you, I like to keep things simple. I have some .270 AI brass prep 4 years ago; loaded some rounds early this year and a week before Thanksgiving, my son hit his target at 936 yards on his first try (1st time behind the trigger) without any problems.

 

[Wado]

If storing prepped brass is a bad idea I'm in trouble. I do the final polish with a wax additive and then with gloves on always I bag it up and seal the bags then they go into ammo cans with desiccant packs and sealed then stored in a dry cabinet at 73 degrees F year around. I learned my lesson with coffee cans lined with cloth and stored in my shop that were exposed to the elements. Even the plastic containers tarnished the brass after a year or so. Two weeks ago I took my 6.5 x 55 to the range and shot up some ammo I loaded at least ten years ago. It all went bang but I noticed the ballistic tips had a little bit of blue corrosion showing where the tips met the copper. Some of the tips were even missing like they just crumbled off. I am sure this ammo had been on several hunting trips exposing it, that's why I shot it up. The rifle shot one inch high centered and the worst three shot group was about 1.75" center to center. I had some better groups with Hornady 140 grain spire points. This old rifle usually shoots better but it is a 96 Carl Gustav with the original barrel that's been sporterized, and the barrel was dirty as heck when I got it home and cleaned it. I don't like to get too ahead on loaded ammo unless I can really seal it up being I live on the Gulf Coast. Another thing happened to this ammo was the labels I used fell off of the shell holders so I had no idea what powder or charge weight they were. Live and learn.

 

[Mikecr]

Maybe I shouldn't have said 'best ammo', as it's totally possible for ammo with a particular barrel & load to shoot better after it's aged. My contention is that there can be changes, and they could change results. These results would of course need to be validated.

We know there is nothing wrong with fresh ammo, as we load develop with it fresh, and anyone competitive is using it fresh.
I see sized/primed, but unloaded cases drift over time. I've seen many posts over the years with concerns about observed performance changes with aged ammo (>3mos old). And I've seen published reports of ammo creeping in dimensions over time.

I have not personally tested aged ammo -vs- fresh ammo.
It would difficult to prove scientifically, as it would take a long time to do so, and we don't currently have a way to measure neck tension itself. I could test using seating force measure, H20 capacity measurements, and a good chrono and targets, but again, it would take a long time to 'prove' one way or another.

 

[MudRunner2005]

Nothing wrong with prepping brass. I fire-form a lot of my wildcat brass ahead of time, then decap it, sonic clean it, then polish it up, and then store it in ziplock bags inside of .50 cal ammo cans (which also seal) for later use. I usually trim it and chamfer and prep the cases before I fireform them.

I don't resize it until I get ready to load it and use it.

 

[Canadian Bushman]

I try not to load anything for my precision rifles that i wont shoot within 3-4 months.

I had a rifle that i used to run very little neck tension on. I once pulled some shells out that were 6-8 mo old ( maybe more i dont recall ), and i could push the bullets in by hand. I ended up pulling the bullets out an extra .05-.1" and seating them with the throat, but they shot terribly.

 

[Mikecr]

Just curious Canadian Bushman, was the last sizing action on the necks downsizing, or expansion? How much downsizing?