Home Forums Hunting & Shooting Ask The Gunwriters Sticky bullets

How much difference is there shooting ammo that is freshly loaded vs ammo that has sat for a week, month, year or more? Curious because when seating, bullets slide in with moderate pressure. After they have sat for a week or two to seat them a little deeper they will pop a little bit before they move. Does this have an affect on pressures and accuracy or is it a small enough amount to not really matter? Do you just load a week or two before you need to shoot so things stay consistent?

Might be a good experiment to shoot fresh load ammo over chrono. Wait a couple weeks then shoot again, Another couple weeks shoot again. Need stable and similar ambient temps, etc for valid test imo.

Or structure long time period test where shoot fresh ammo. Wait one year choosing a day when temps, etc are similar and shoot over chrono.

Assume ammo is stored as normal for you.

Me no gunscribe, but for hunting and steel clanging I like a lot of neck tension, whether chemical reaction or the Lee squeezer. Did some half assed experiments when the Lee squeezers first were offered, the chronograph seemed to prefer a lot of neck tension. I know this flies in the face of the F class guys and benchresters. But in my last century military cartridges, 6.5 Swede thru 8x57 with mostly IMR stick powders, and Federal Match primers, it works.

Metal cohesion is a real thing, I remember speaking to an old guy about it when I was 7 or 8 years old.
I know the big trend in later years has been to load your ammo long and the morning of the match to seat it where you normally do to break the accumulated tension.

I have a theory about the Lee factory crimp die and it is this:
The factory crimp die creates an equal repeatable neck tension that "overides" the usual conditions of uneven neck tension.
Just for example , if you have 100 rounds of same lot brass, 50 rounds loaded with neck tension ranging from .002 to .020 , and 50 rounds loaded with the factory crimp die that works out to say, .025 neck tension, you will have better consistency with the brass that was crimped.
Mind you I have never tested this theory, it's just an idea.....
Cat

catnthehat,

I have tested that, and my results indicated you're correct--at least with "average" brass having necks of slightly different thickness.

With really consistent brass, or neck-turned brass, the crimp die didn't make nearly as much difference, if any.

HAH! Also proves my tenet " even a blind squirrel can find nut every now and then" LOL
Cat

I used to load up large batches of rifle shells and sometimes on a hunting rifle, not shoot them up in 5 or even 10 years. Then when checking zero on a rifle it wouldn't group but when I loaded up some fresh ammo with the same recipe (and same powder and primer lots) it shot fine. Mentioned this to a friend who shot BR and he confirmed that he had seen a difference in fresh vs a year or so old ammo. Now I only load what is needed for a hunt and pull or shoot it up.

Oh great... ANOTHER variable to worry about!

Just load ammo a little long, and do a final seating operation prior to using it.

So I guess this what is referred to as a cold weld.

True for fired brass with necks coated with carbon?

Not as much as clean, bare brass necks.

JB, I thought that I read some place where you wrote that you “gave up on crimping ammo, even for ammo for tubed magazines”.
Is this because you neck turn all of your brass and/or you only buy very consistant brass, like Petersons or Lapua?

I probably said I'd given up crimping rifle ammo after selling my .416 Rigby. As Elmer Keith observed many years ago, neck tension has far more to do with keeping bullets in place than crimping.

Still taper-crimp black-powder rifle rounds, which works somewhat like the Lee crimp die. Still roll-crimp harder-kicking handgun rounds. But haven't crimped a .30-30 round in many years.

Same with the 30-30 for me. Such a long neck and light recoil on that round…

There have been several threads regarding "cold welding" in the past. I seem to remember it happening with new brass as well as polished/tumbled brass and someone wrote that's why they don't clean their brass now.
I know from personal experience that it's for real. A year or 2 ago I went to chrony some 30-06 loads with 180 Nosler Partitions that I had loaded in 2014. The first shot kicked quite a bit harder than normal and when I checked the chronograph it was reading over 2900 fps. I brought them home to check them out. I remembered reading about cold welding so I pushed them in a bit with the seater die to see what happened and there was a distinct pop when I pushed the bullet down. I wound up pulling them all with a collet style bullet puller and re-seating them.

If you've subscribed to Precision Shooting for a while, you might remember Randolph Constantine writing about cold welding spoiling his day. Constantine was a bona fide rocket scientist and delved into the chemistry and mechanics of the cold welding phenomenon he experienced.

Highpower shooters have known about it from before I started. "Seat long when you load for the season. Final seat day before the match." was the convention I was taught Same as when Jordan Smith posted here;

Oh, yes, I agree. Chris you the man. ha ha... If only just in your own mind.. Clean is good, but if you guys just keep your necks carbon fouled, this wouldn't even be a fu cking issue. Just a fyi... It begs the question of how many of you guys actually shoot? I can understand city folks not knowing chidt, but come on.

I have a few rifles that see 90% hunting and 10% range use. I do have handloads a number of years old for those rifles. I guess it won't hurt to give em a pull and seat deeper prior to use despite necks being carbon fouled.

Any idea how long it takes cold welding to take place on new brass? Carbon fouled brass?

How do factories account for this?

Factory ammo is crimped so it overides any inconsistencies in tension due to brass thickness , etc.
Cat