Does ammo loaded weeks earlier become progressively inaccurate over time?

[NamibHunter]

Commented earlier in another thread that i have seen some evidence that handloads stored for weeks or months have higher SD, higher speed, and far lower accuracy compared to ammo loaded the previous evening and shot the next day. [Will try to figure out how to post a link.]

Took 6.5 Creedmoor handloaded ammo to the 600 yard range today. The box of ammo consisted of a load recipe that previously gave an SD of 4.4 fps and a hit percentage on the small 4” steel targets of 75%-80%. We are 50 miles from the Gulf Coast, so there is almost always some wind in the 5-12 mph range, and i am happy with that result for now. As my wind reading skills get better, i expect that to improve some. Vertical spread at 600 was 1.5” on a good day and 2.5” most of the time. Very enjoyable to shoot ammo like that!

Today my (meticulously prepped) neck turned weight sorted Lapua brass, shooting H4350 and weight sorted Berger Hybrid 140’s (jumped 0.015”) gave an SD of 25.9 fps measured via the Labradar. Yes over twenty five! Slowest was 2736 and the fastest was 2892 fps from a 30” Shilen barrel (the two that went over 2860 fps showed half moons, and other pressure signs). Ambient temp was a perfect 68 F. This is not good!

Shot 25 rounds, got rather frustrated and went home, then decided to reseat the remaining ammo for a long jump that also worked well before. I use a hand die and an arbor press with force measurement so i can cull out the cases with exceptionally high seating pressure/seating force (measured in lbs). My notebook said the cases previously all seated with a seating force of 8-15 lbs, which is low and adequately consistent, given prior results. This time the k&m guage read anywhere betweeb 24 lbs and 64 lbs, which is a massive increase. And poor consistency. Ammo was 10 days ‘old’. I usually load on a Friday evening and shoot it Saturday or Sunday. This time work interfered and it was close to freezing last weekend. Typical spring weather in Texas.

Have any if you seen similar issues before?

Have read up a bit about bimetallic corrosion before (search for this term and you should find the prior thread). Is the bullet and brass ‘welding’ together because of corrosion, driven by high humidity? This is at least the third time i have seen this particular problem. It does seem to help to load the day before, or to reseat at the bench. One of the many benefits of a wilson hand die and an arbor press. Easy to pack. Micrometer seater works very well to keep ammo straight and consistent.

Btw: Used mica lube on the bullets and it did not prevent the problem this time, so have to take back what i recommended before...

Any personal experience? Is this only a problem in humid climates??

 

[mheimer_45]

Yes I have that same damn problem with 6.5 ammo I loaded over a year ago. Apparently it’s called bullet weld. Should have used graphite while seating bullets. I’m looking at over 200 rounds that will not pull without seating deeper first with lots of force.

 

[isofahunter]

I have never experienced but some guys I know seat long when loading, then the day of shooting they make a final seating adjustment to desired length to avoid this.

 

[ken4570tc in WY]

Interesting!

 

[culater]

Do you anneler you brass? I use to have your problem until I started to use the AMP annealer. Still like to get the arbor press with gauge. I still get one or two that seat a little harder than the others. But I have ammo sitting for almost 6 months I took it out it shot very consistent to my dope

 

[whiskeysierra762]

For my reloading process on match ammo I will ultrasonic clean, anneal, FL size, trim, then tumble to get case lube off. Then when I go to load them I run them through a neck die using graphite lube from Redding. Seems to work so far.
Im interested in what everyone else has to say on this though.

 

[Sniper266]

I’ve also experienced this problem and have since just delt with loading small batches a day or two before shooting. Ive also seen graphite lube mentioned twice above. What is this stuff and is it designed to prevent cold welds?

 

[Mordamer]

I loaded some ammo for 6.5x47 Lapua and shot it over 1 year later. The velocity was the same and the accuracy was still stellar. I clean my brass with corncob or Walnut and it leaves a little carbon in the necks. I believe this helps prevent the cold welding of the brass to the copper jackets.

 

[Tnc]

Don’t clean the brass so well. Leave a little carbon residue in the case necks. I’ve done this for years and I haven’t seen accuracy decrease with handloads that sat for years prior to using.

 

[ctso030]

i have always loaded my bullets and they sit for quite a while before i shoot them. my velocity fluctuates more than i would like. after watching youtube, i polished all the expander balls in my sizing dies , used imperial dry neck lube before sizing, then dipped my bullets in the dry lube before i seated them. i seems to make sense that applying the lube to the necks and or the bullets will make for a more consistent release. i just loaded the first batch havent had a chance to shoot yet.

 

[Jackomason]

This porblem pops up when you use SS media and clean the brass perfectly. A little carbon goes a long way.

 

[Snuby642]

I have not seen any cold welding yet.

I decap and tumble with walnut and a mix of mineral spirits and nu finish wax. 3-4 hrs if dirty.
I resize then a quick tumble to get rid of lube.
I work the brass as is necessary and another 2 hr tumble.

I belive this builds up a slick wax coat in the throat.
I dip the neck in dry graphite and seat, the bullets go in like butter, estimate 5lb max.
I get 0.0025 neck tension.

I'm doing batches of 100 and there is always another task to do while waiting.
I time my tumbling with a cheap auto timer on the outlet and walk off.

Ocd maybe but timed to other tasks.

 

[lightman]

I have not experienced this problem yet. I load my hunting ammo in lots of 100 and sometimes it takes years to go through it. But I don't remember if any of my older ammo was wet tumbled or not. The cold welding theory has some merit and I don't think its anything new. I have a little plastic doodad with a slip top that holds 3 nylon bore brushes and came with either motor mica or graphite in it and was made by Bonanza maybe 40 years ago. It was made to apply dry lube to the inside of case necks.

 

[gunsnjeeps]

Cold welding was a big debate a while back. I've never noticed letting ammo sit from year to year.

My brass sits to air dry and may not get loaded for months before I get around to it. I prep brass by the 500 round lot in the winter. Prime it when it's dry and load about a hundred rounds at a time over a few months and shoot 60 rounds a month

 

[Deleted member 10043]

I don't notice a material problem. I just make sure to give the case a good shake or two to loosen up the static powder. A little neck lube too.

 

[nso123]

Would this not be a problem with factory ammo using new brass, or do they apply something to the neck during manufacture? I have never experienced it, but the only ammo I have thta sits like this is hunting ammo, or occasionally handgun ammo.

 

[NamibHunter]

I have not experienced this problem yet. I load my hunting ammo in lots of 100 and sometimes it takes years to go through it. But I don't remember if any of my older ammo was wet tumbled or not. The cold welding theory has some merit and I don't think its anything new. I have a little plastic doodad with a slip top that holds 3 nylon bore brushes and came with either motor mica or graphite in it and was made by Bonanza maybe 40 years ago. It was made to apply dry lube to the inside of case necks.

Thanks for the informative replies, food for thought. Several useful ideas here that i plan to try out.

Replies to earlier questions: I do not use ss wet media tumbling, either corn cob or walnut media. Walnut is treated, corn cob is untreated. Sometimes in combination with ultrasonic cleaning. Typically run it for 2-3 hours in a tumbler, and 9 minutes in ultrasonic cleaner. Yes sometimes in forget to turn it off in time, and then it might run for 6 of 8 hours. Getting a timer is a great idea! Inside of cases usually have some carbon left (2 hour runs in tumbler). But sometimes the cases are shiny clean, with very little or no carbon in the neck. I think i am “over cleaning” the cases...

In this case powdered mica was used (dipped the bullets), corn cob media plus ultrasonic cleaner. Will try graphite dry lube as well. AMP annealed.

I guess if the problem persists i will have to reseat at the bench. Doable, and have done it before for load development, but people do look at you funny. ?

I wonder if the folks who have never experienced this problem live in dry inland climates? Gulf coast is very humid in summer (80% plus is typical).

 

[918v]

Would this not be a problem with factory ammo using new brass, or do they apply something to the neck during manufacture? I have never experienced it, but the only ammo I have thta sits like this is hunting ammo, or occasionally handgun ammo.

Factory new cases are waxed.

 

[Gunfighter14e2]

Commented earlier in another thread that i have seen some evidence that handloads stored for weeks or months have higher SD, higher speed, and far lower accuracy compared to ammo loaded the previous evening and shot the next day. [Will try to figure out how to post a link.]

Took 6.5 Creedmoor handloaded ammo to the 600 yard range today. The box of ammo consisted of a load recipe that previously gave an SD of 4.4 fps and a hit percentage on the small 4” steel targets of 75%-80%. We are 50 miles from the Gulf Coast, so there is almost always some wind in the 5-12 mph range, and i am happy with that result for now. As my wind reading skills get better, i expect that to improve some. Vertical spread at 600 was 1.5” on a good day and 2.5” most of the time. Very enjoyable to shoot ammo like that!

Today my (meticulously prepped) neck turned weight sorted Lapua brass, shooting H4350 and weight sorted Berger Hybrid 140’s (jumped 0.015”) gave an SD of 25.9 fps measured via the Labradar. Yes over twenty five! Slowest was 2736 and the fastest was 2892 fps from a 30” Shilen barrel (the two that went over 2860 fps showed half moons, and other pressure signs). Ambient temp was a perfect 68 F. This is not good!

Shot 25 rounds, got rather frustrated and went home, then decided to reseat the remaining ammo for a long jump that also worked well before. I use a hand die and an arbor press with force measurement so i can cull out the cases with exceptionally high seating pressure/seating force (measured in lbs). My notebook said the cases previously all seated with a seating force of 8-15 lbs, which is low and adequately consistent, given prior results. This time the k&m guage read anywhere betweeb 24 lbs and 64 lbs, which is a massive increase. And poor consistency. Ammo was 10 days ‘old’. I usually load on a Friday evening and shoot it Saturday or Sunday. This time work interfered and it was close to freezing last weekend. Typical spring weather in Texas.

Have any if you seen similar issues before?

Have read up a bit about bimetallic corrosion before (search for this term and you should find the prior thread). Is the bullet and brass ‘welding’ together because of corrosion, driven by high humidity? This is at least the third time i have seen this particular problem. It does seem to help to load the day before, or to reseat at the bench. One of the many benefits of a wilson hand die and an arbor press. Easy to pack. Micrometer seater works very well to keep ammo straight and consistent.

Btw: Used mica lube on the bullets and it did not prevent the problem this time, so have to take back what i recommended before...

Any personal experience? Is this only a problem in humid climates??

Load them as long as you can then set to correct depth the night before shooting, becomes a none issue for point scoring targets.

 

[MK20]

I would also watch your storage of your rounds. The climate down there can play hell with ammo.

 

[MarinePMI]

I'm thinking about washing the annealed and sized cases in car wash soap (that includes a polymer wax) as a solution to cold welding issue after tumbling in SS/annealing/sizing. I'll see what happens and post a response if anything of value comes from it....

 

[Sniper260]

As a competition shooter with a good handful of well known buddies. The snswer is yes.

But it depends on how picky you are with accuracy for it to make a difference to you. The phenomenon is called bullet weld.

 

[Deleted member 10043]

Brass and copper are too similar to create galvanic corrosion. Plus they are both galvanic protected. Plus you need a third element to create the phenomenon so stay away from introducing bullshit into the neck loading process. Wax/petroleum based lube is fine to neutralize carbon. I don't understand the current fad of sticking graphite (carbon) in the necks. It is the third element introduced in the loading process that actually gets corroded and can cause the problem. This is one reason why steel cases are copper washed or coated with something so that you don't have a steel case in direct contact with a copper jacket bullet.

 

[Gunfighter14e2]

Most all powders have a % of carbon in them, AFAIK.

 

[918v]

Brass and copper are too similar to create galvanic corrosion. Plus they are both galvanic protected. Plus you need a third element to create the phenomenon so stay away from introducing bullshit into the neck loading process. Wax/petroleum based lube is fine to neutralize carbon. I don't understand the current fad of sticking graphite (carbon) in the necks. It is the third element introduced in the loading process that actually gets corroded and can cause the problem. This is one reason why steel cases are copper washed or coated with something so that you don't have a steel case in direct contact with a copper jacket bullet.

Graphite is needed when seating bullets in annealed necks, otherwise the seating effort becomes unbearable.

 

[Deleted member 10043]

Most all powders have a % of carbon in them, AFAIK.

Bingo! Also, the sheer violence of a copper jacketed bullet leave the cartridge is going to leave copper inside the neck, which is actually beneficial to leave alone.

 

[RTH1800]

I have seen first hand extreme cases of cold welding. I end up with a lot of ammo loaded from the '50's to today. Some in new brass and so marked at the time of loading. I get this ammo when I do estate purchases. I am not opposed to shooting reloaded ammunition unlike most folks who are likely smarter than I am.
Prior to firing ammo reloaded by others, I always check any notes or data present. I then pull a few bullets, check to see if data corresponds to actual powder charge, bullet weight etc. If it lines up I shoot the stuff. I have done this on literally hundreds of thousands of rounds over the years.
Long to short is that I have seen several incidents where the bullet was welded or corroded to a huge extent. Looks fine on outside often but not always. Inside the green crud can be as large as a bullet. More often than not in new brass. I suppose this due to being chemically clean??
Now I will always bump the bullets on older ammo. The badly corroded ones will not push in but crush the case. It is fully welded and I have no idea what would happen if it was fired but nothing good I am sure.
I now lube all my ammo inside the neck with my sizing lube. I am concerned graphite will cause bore wear.

 

[Deleted member 10043]

Anyway, I don't see any problems with weeks in storage or even a year or two as long as it is stored properly.

 

[Gunfighter14e2]

I am still shooting 308 ball I loaded in the mid 70's. Still shoots to minute of head to were, it was loaded to back when. In all the stuff I have loaded an shot I've only seen a 1/2moa difference across the board. For that last point in a race yes it will make a difference , but over all me (the shooter) is still the weak link.

 

[NamibHunter]

I would also watch your storage of your rounds. The climate down there can play hell with ammo.

Maybe store in a sealed container with freshly regenerated desiccant inside? Worth a try...

 

[NamibHunter]

Load them as long as you can then set to correct depth the night before shooting, becomes a none issue for point scoring targets.

Have tried this at least three times and yes it worked! Just an additional step and a complication that i would love to out-engineer.

Noticed that seating force went from 8-12 lbs (<6 lbs allows the bullet to be rotated by hand) so very light neck tension all the way to 60-120+ lbs, while a few remained mostly unaffected. It felt like i was about to destroy the k&m arbor press, bullets would stick like crazy and come loose with a loud thunk! No sliding, just a violent sudden thunk. Felt like the bullet was spot welded to the brass.

Also very variable seating force, from 20 lbs to 120+ lbs range. Ridiculously bad! Reseated at the range a few times and that worked too, but you have to carry additional gear.

One or two days delay between loading and shooting does not seem to cause any problems. But a week will do it! A month is even worse. I cannot be sure but summer time seems to be worse, which makes humidity the prime suspect...

I wonder if the powder is not absorbing water vapor while sitting in the powder thrower for a week or more, and that evaporares and “rusts” the neck and bullet from the inside of the case, especially where these components were scratched during seating (which happens). [Just pull a few bullets and inspect... ]. I guess i need to put the remaining powder back in the bottle evey time? Add a bag with desiccant too?

Tried both Imperial dry lube (graphite/carbon?) and Franklin Arsenal mica lube. Seems to help some, but not a true “cure” either. I guess the scratches cut through the thin layer of material?

 

[NamibHunter]

Anyway, I don't see any problems with weeks in storage or even a year or two as long as it is stored properly.

Culpeper, could tou advise on what proper storage entails? What do you do? And do you live in a high humidity climate?

 

[KZP]

I've tried the dipping necks in graphite and tapping process, but found it created worse random spikes in velocity and point of impact. It did make the bullet seating process very smooth though.

 

[tsu45]

Graphite is needed when seating bullets in annealed necks, otherwise the seating effort becomes unbearable.

Can you expand on this?

 

[wapiti16b]

I live in a very high and dry environment and even in this climate I noticed variance with fresh vs 3 to 6 month old loads. I started using HBN coated bullets and see very little difference in loads 1 year or so old ( hunting loads ). I will try graphite also and seating match loads long and re-seating in the future. I never considered vibrating /shaking loads to restore powder to just loaded condition but I always tap my loaded magazines out of habit!

 

[Deleted member 10043]

Culpeper, could tou advise on what proper storage entails? What do you do? And do you live in a high humidity climate?

Store indoors in controlled environment. Like in the house, not the garage. I live in a dry climate. SE New Mexico.

 

[NamibHunter]

Factory new cases are waxed.

Is it possible to wax coat your bullets? Or a bad idea??

I can see why HBN would work. But it is a major commitment in new gear....

 

[NamibHunter]

Store indoors in controlled environment. Like in the house, not the garage. I live in a dry climate. SE New Mexico.

Have always stored loaded ammo in my reloading room, which has AC. In closed ammo boxes. The AC reduces indoor humidity to below 60%. Springtime the AC / furnace turns off when ambient temperature is close to 70 deg F. Then inside and outside humidity is similar. Not sure if this matters.

I am going to try storing a batch of ammo in an airtight glass container with desiccant. Then reseat 5 every week and record seating force.... and see if it goes up or not.

Btw: Have now seen this problem with Berger and Hornady bullets. Brand of bullet does not seem to make a difference.

 

[918v]

Is it possible to wax coat your bullets? Or a bad idea??

I can see why HBN would work. But it is a major commitment in new gear....

Some bullets are already waxed. No harm in waxing buckets that aren’t. But why would you wanna do that when it’s easier to apply graphite to the inside of the neck?

 

[clcustom1911]

I might be crazy, but as I do my final tumble of my brass, I spray some Meguiars NXT quick wax on the brass, then I put them in. As they tumble, I spray a little more so the media that's flowing into them can distribute the wax as well.

The only time I have ever experienced the sticky bullet issue was when I really cleaned the brass really well, and did not do the wax coating gig........ And my brass wasn't as shiny. Can't be having that. Looking good lowers SD's and ES's. Everyone knows this.

 

[Deleted member 10043]

Another thing to remember is powder in the case, especially cartridges stored bullet tip down, can result in noticeable as well as unnoticeable hang fire. Jostling the ammo still in the case is something I do to avoid this. Cartridges stored bullet down for a long time are especially suspect. Turn the case upside down a few times. Powder in a loaded case don't like sitting still for long periods. Results in inconsistent burn time from case to case.

 

[Gunfighter14e2]

Also very variable seating force, from 20 lbs to 120+ lbs range. Ridiculously bad! Reseated at the range a few times and that worked too, but you have to carry additional gear.

Sounds like you have some very hard necks as well. When dealing with same set the bullet to normal depth then let set at least 3 months. Collet pull the bullets right before the match an reseat that bullet back into that same case. You'll find the neck tension just about perfect for bench or prone shooting with a bolt gun. Poor mans way of getting quality ammo if the load is correct for that stick w/o all the gaming gear.

 

[wapiti16b]

Culpepper, we are nearly neighbors!. I live just SE of ABQ we have a slight micro climate colder and usually wetter than ABQ my ammo is loaded and stored at room temperature and before coating my bullets with HBN I did notice a difference in my SD , not so much now .

 

[NamibHunter]

Sounds like you have some very hard necks as well. When dealing with same set the bullet to normal depth then let set at least 3 months. Collet pull the bullets right before the match an reseat that bullet back into that same case. You'll find the neck tension just about perfect for bench or prone shooting with a bolt gun. Poor mans way of getting quality ammo if the load is correct for that stick w/o all the gaming gear.

Actually, i used the blue propane torch from Home Depot to anneal neck turned cases almost every time, counting to 7 seconds. The 7 seconds were determined with Tempilaq. AMP annealer arrived last week and seems to work very well. Pretty sure it is not work hardening of the neck that is causing my issues. Took ammo that i loaded two days earlier (loaded long) and then yesterday reseated at the bench with an arbor press and a Wilson hand die, and the amount of force required was very mild. The ammo then shot 2-3” groups on steel at 400 yards. Could hit the 3” target every time, in an 8 mph wind that changed direction a little. Forgot to take the Labradar, but the ammo performed well.

The problem only appears if i load ammo and let it sit in our humid climate for a week or longer. I record the seating force in lbs and write that on the case with a permanent marker. If i reseat them, the seating sometimes force goes way up, by 10x, while others remain mostly the same as before. I think the bullet gets “cold welded” to the case. Mica and graphite dry lube have not cured the problem. All that has worked so far is to load the night before, or reseat at the bench. Now experimenting with cleaning the cases less thoroughly (corn cob media, done outside the house because of white dust).

Btw: AMP induction annealer (mark ii model) arrived, and it is very fast (2.5 seconds of heating time for a Lapua 6.5CM case) and very consistent (based on where the coloration stops on the body of the case). Had to adjust my Redding type S FL die, seems brass spring-back is a lot less than gas flame annealed cases. Shoulder is softer than before. Can now anneal 50 cases in about 10 minutes, so planning to do it every time. Effortless. I have high hopes for this device. Just wish it wasn’t so pricey, but oh well.

Plan to load a batch of 50 and let them sit for months, and reseat a group of 5 every week. Then plot a graph and see how time affects seating force... i think it might be rust forming inside the case, between neck and bullet.. Gulf Coast climate and our high humidity.

 

[NamibHunter]

Some bullets are already waxed. No harm in waxing buckets that aren’t. But why would you wanna do that when it’s easier to apply graphite to the inside of the neck?

Nu Finish arrived from Amazonia. So how much Nu Finish car polish should i add to the corn cob media to ensure a coating of polymer wax remains inside the necks? I guess too much on the outside of the necks and the cases may not grip the chamber properly?

 

[Snuby642]

I mix my wax with mineral spirits and put in a condiment squirt bottle.
2 parts wax to 1 part spirits .

I turn the tumbler on and add 2 full squirts, let the tumbler distribute the wax till all clumps are gone before adding brass.

? Brass too slick or shiny making problems? Not ran into that.

Since your media is dry some extra wax on first run may help.

 

[Wormydog1724]

Learn something new everyday.

 

[captainemil]

I have the same issue on my 300 win mag in the past, did not know what caused it

 

[abn31c]

I use lyman media, the red one. It leaves a reddish residue inside the neck, and a dollop of carnuba car wax leaves a smooth waxy finish on the out side. And it smells good!

 

[Jammer Six]

The problem with time is that it changes everything, and makes causes hard to pin down.

I'm not experienced enough with rifles to comment, but in handguns, I've seen loads that were stored for months suddenly change numbers, and I believe it was because the temperature changed. The main clue was that as time wore on the day I went shooting, the numbers changed as the ammunition got colder.

I was in an interesting discussion that day with another shooter who opined that the same thing was happening to him that day, and he believed it was the temperature and the humidity changing. I don't think it was the humidity, I think the rounds are sealed tighter than that.

But I do think the changing temperature affected the load. The load sat in my basement at room temperature, then the day I went shooting, the temperature dropped from about forty degrees down to just below freezing, around thirty degree, and the accuracy reflected that drop.

I don't think the time affected it, I think if I had loaded it at room temperature and then gone straight to the range, the same thing would have happened if the temperature had dropped like that.

So I don't think it's the time, in and of itself. I think it's some of the things that change as time goes by. Like the temperature.