Rotating carry ammo?

[TheRaskalKing]

Hey all,

How often should CCW ammo be rotated? When I practice, I use the mags I carry, but not my carry ammo, though I do practice with the same bullet weight. How often should I be switching out my carry ammo?

[SerenityNetworks]

My CHL instructor suggested at least once a year with twice preferred if it is kept often in the car. The rationale was that the summer heat, such as in Texas where I live, is very hard on gunpowder. It also impacts the seal between the bullet and cartridge. When a hot cartridge cools it forms a vacuum that will pull air - and the moisture in it - into the case. This also is not good for the gunpowder. Therefore he suggested you shoot out your carry ammo and replace it at the end of summer - at the minimum. Of course it is also good practice to know how your carry ammo feeds and shoots, so rotating the ammo satisfies this need too.

I have no idea whether his rationales are accurate or not, but they seem sensible to me.

Regards,
Andrew
____________________________________
NRA Life Member
There are some ideas so preposterous that only an intellectual will believe them. - Malcolm Muggeridge

[Crow Hunter]

You shouldn't keep rechambering the same round over and over again, there is always the possibility that you can get some bullet setback that could cause pressure problems.

Also, if your carry gun is kept in a vehicle part of the time, eventually the huge temperature changes will kill the ammo. I had a magazine that I forgot I had for a year or 2 in my old truck. Out of the 14 rounds in the magazine, 3 of them failed to fire.

I always shoot at least the round that is in the chamber when I practice and replace that round with a fresh one (put it on the bottom of the magazine).

[SerenityNetworks]

Originally Posted by Crow Hunter

You shouldn't keep rechambering the same round over and over again, there is always the possibility that you can get some bullet setback that could cause pressure problems.

Thank you. I hadn't thought of that. I'll be changing my habits.

Andrew
____________________________________
NRA Life Member
There are some ideas so preposterous that only an intellectual will believe them. - Malcolm Muggeridge

[LockedBreech]

I change mine once a year, and any time I need to unload my carry ammo and reload it later, I set aside the previously chambered bullet and pick a random one that was in the magazine to be the new chambered bullet. This is especially important as my defense round is a 180-grain .40 S&W, particularly susceptible to setback.

While I'm a huge believer in my 180-grain Gold Dot, I'll probably switch to the 165-grain Gold Dot or the 165-grain HST next time, just to make the setback slightly less concerning. The bit of extra "snap" won't bother me, I used to carry 155s.

[deadcoyote]

This is in no way scientific, I just know as an LEO both departments I've worked for has had us rotate out our work issue of ammo every 90 days so I just do the same with my off duty pistol as well. Again, no evidence to this whatsoever, just 13 years of habit.

[Dragline45]

I switch the ammo out for fresh rounds when the case rims get chewed up enough from cycling through the gun. Since the stuff is pricy I don't shoot them I put them aside so I have a few boxes of premium hollow points lying around for each caliber.

[9mm]

12 months/1 season of each.

[TailGator]

It is easy to set up a system rotating the top round to the bottom when you reload a given magazine. I think that advisable to avoid problems from setback.

Personally, I shoot out my defensive ammo just once every 2 years, and in three decades I have not had a single round that failed.

[drail]

If a round has set back why would it be any safer to fire from the bottom of the magazine? That doesn't really solve the set back problem. Repeatedly chambering a round is just asking for trouble. Don't do it. The solution to bullet setback lies in the hands of the manufacturers and their lack of quality control but they couldn't care less if your gun blows up. I have been handloading for 30 years and I have never had any rounds "set back". There is no scientific reason for "rotating" your carry ammo. But if it makes you feel better go right ahead. If ammo went bad just from temp variations then we would have lost WW I and WW II and the Korean and Vietnam wars and everyone in Irag would be having failures due to ammo.

[SerenityNetworks]

Originally Posted by drail

Repeatedly chambering a round is just asking for trouble. Don't do it.

Based upon these discussions, I've numbered my SD cartridges. When I empty the chamber and magazine for practice then I can reload placing the last chambered cartridge at the bottom. As I rotate, it will minimize the number of times any cartridge will be rechambered. With my mag, a cartridge will not be rechambered until the 7th reloading. So then the question is how many times can you rechamber a cartridge before there is risk?
____________________________________
NRA Life Member
There are some ideas so preposterous that only an intellectual will believe them. - Malcolm Muggeridge

[drail]

I have seen factory ammo that will set back dangerously on one or two rechamberings. Some guns will be more prone to setting back a round than others but the problem is still poor QC by the manaufacturers. I have also seen new sealed boxes of factory ammo with primers inserted backwards or no flash hole in the case or bullets set way down into the case before you even take it out of the box. Inspect every round you load into a mag or cylinder carefully and if doesn't look right DON"T use it. They make no guarantees on ammo and they are lawyered up like you wouldn't believe.

[SerenityNetworks]

Would checking overall length with a caliper be sufficient? What would be allowable? (Qualified noob question.)
____________________________________
NRA Life Member
There are some ideas so preposterous that only an intellectual will believe them. - Malcolm Muggeridge

[Skadoosh]

drail wrote: I have seen factory ammo that will set back dangerously on one or two rechamberings.

Really? What brand?

[Crow Hunter]

Personally I just shoot them and buy new rounds.

$1.50 for a new high quality HP round is a lot cheaper than potentially blowing up my pistol with my hand holding it.

If ammo went bad just from temp variations then we would have lost WW I and WW II and the Korean and Vietnam wars and everyone in Irag would be having failures due to ammo.

It isn't temperature extremes that kills primers. It is thermal cycling that does it, high to low, low to high, especially combined with moisture. It accelerates "aging" of components. We use it all the time in accelerated life cycle testing.

The priming compounds used in older corrosive primers are less susceptible to it than more modern compounds, non corrosive primers used today. (One of the reasons the Russians continue to use corrosive primers in their military ammo)

Hollowpoint ammo, using commercial primers are even more susceptible to it because, unlike military ammo, it isn't designed survive the same level of temperature cycling and isn't sealed the same way military ammo is. It is designed to be shot fairly frequently.

Yet even military ammo has a finite shelf life and this is considerably shortened if it has been exposed to temperature extremes. That is how we get a lot of our surplus ammo from overseas. It has exceeded it's shelf life and/or has been subjected to extremes that make it suspect for military use and such it was surplused.

While anything is subject to failure, (I have had brand new dud rounds), I want to stack the odds in my favor. So I try to keep reasonably fresh rounds in my carry piece, even if it means I have to replenish my stash more than once in a decade.

[Crow Hunter]

Really? What brand?

Personally, I have seen UMC .357 Sig do this on several occasions.

Kind of made them look like 120mm Sabot rounds for a M1 Abrams.

[zincwarrior]

I did not know this.

A potentially very important lesson here both on running through rounds, and rechambering a particular round.

[TunnelRat]

I actually do it this way.

I shoot 124 gr+P Speer Gold Dot. I keep three magazines loaded. I keep one round on top for 2-3 months. At the end of that I just shoot off that round at the range and the next one moves its way to the top and another comes from the box. I haven't had any issues yet.

I personally avoid rotating the round being chambered. To me this just means every bullet gets a little bit of setback. I like having only one so that I can easily compare it to the others in the magazine to see it it has experience a lot of setback from what it was originally.

[RBid]

I fire through a mag each month, to keep a feel for it. I find that I perform better with the Speer Gold Dot 9mm +P 124gr than I do with range stuff, and I enjoy shooting it.

[TunnelRat]

I enjoy shooting it.

+1.

[sgms]

I also change out carry rounds yearly and also rotate rounds in mags. at each unloading.

[rodfac]

Front Sight, the NV based shooting institute, recommends rotating your carry ammunition and specifically warns against repeated chambering of the same round...they suspect that bullet setback deeper into the case may be a problem and WILL increase pressures. I abide by their recommendation. Rod

[RBid]

The first time my brother fired a +P 124gr GDHP from my SR9c, he had to set the pistol down. He was laughing pretty hard. The crack and the little flash... It's just plain FUN.

I shoot enough range ball to feel good about cracking off a few 'Dots. Indulge yourself

[Kreyzhorse]

I try to shoot mine and rotate about once a year. Ammo if properly treated should last for decades but rotating it just makes good sense.

[Theohazard]

drail posted:
If a round has set back why would it be any safer to fire from the bottom of the magazine? That doesn't really solve the set back problem. Repeatedly chambering a round is just asking for trouble

I think the point is that by constantly rotating the top round to the bottom of the magazine you're not re-chambering the same round over and over again, therefore delaying or preventing the setback problem in the first place.