Do you guys think storing ammunition in the garage is ok in terms any negative affects of heat/humidity/cold ?

Depends on the conditions in your garage. Most garages are relatively dry and mild.
Here's the publication that gives all the details:

Sporting Ammunition

Item #202 - Discusses the characteristics of sporting ammunition, its appropriate handling and storage, including characteristics of ammunition caught in a fire.

http://www.saami.org/Publications.cfm

Yes. I stored about 1200 rounds of Navy 9mm in my garage (coastal California) for about forty years. Got it for the BHP that I carried on two carrier cruises to Vietnam. Became interested again in shooting about five years ago and fired off about five hundred rounds of that stuff. Every one went boom and ejected. Gave the rest away; big mistake as I've since fired several thousand rounds of other stuff through that weapon. American factory-made ammo is almost immortal. As for Chinese, or Libyan, or . . .

Cordially, Jack

I store my ammo in the garage too. I keep all of it in 30 cal ammo cans and keep them just off the concrete. I figure that the cans will counter any moisture or humidity issues which leaves temp concerns. My garage see temps from 20-110 degrees throughout the year and to this point (10 years) I have not had any problems with ammo. I personally think the temps in the ammo cans may not see those temp extreams because the temps are not sustained for long enough to bother the stuff. I go through my ammo faily quickly so it dosn't collect dust.

I store mine in amm cans also ,but i do run a dehumidifier.

Humidity is the killer. Storage in ammo cans or similar will permit storage in a garage for extended periods. In Vietnam a lot of ammo was stored out of sealed ammo cans in Conex containers that seemed to intensify the already high humidity, and some ammo that had been stored that way for a few years didn't work well. Simply putting in a light bulb and leaving it on kept the humidity low enough so that the problems ceased. Proper rotation of stocks is a big help too. When the cardboard in the boxes and packing is soggy and covered with fungus, the ammo may not be the best.

quote:

When the cardboard in the boxes and packing is soggy and covered with fungus, the ammo may not be the best.

Oh man---Funny, I love it.

To each his own, but I have always stored my ammo inside. Given the cost of ammo these days, I'm going to take the best care of it I can. Storing in a garage may increase the chances of someone other than yourself taking some.

I believe the old NRA Handloaders guide tested powders years ago, and concluded that only moisture destroys BLACK powder by separating it's components (sulfur, saltpeter, etc). High heat did nothing.

Smokeless was weakened by high heat only.

It was noted that surplus powder dealers at one time stored powders like 4831 in leaky rail cars. They showed pictures of this, and noted that once dried out, it functioned perfectly. I used to buy the stuff in paper sacks, measured out of larger containers.

High heat degrades the intensity of burning.

I am NOT saying that soaking wet smokeless works well. The moisture simply doesn't destroy the chemical composition.

Primers are another matter.

I was involved in training Kuwait Army armoured vehicle crews in the middle 1990s, some five years after the Iraq invasion of August 1990. Most of the ammunition used was Pakistani 1980 vintage 7.62x51 NATO caliber for the coaxial machine guns, and even after being buried in the Kuwait desert for more than two years, it all fired perfectly. The quantity was approximately 20,00o rounds per monthly training session, for four consecutive months.

I store some in my polebarn in large Ziplock bags. Never had a problem.

quote:

Originally posted by john traveler:
I was involved in training Kuwait Army armoured vehicle crews in the middle 1990s, some five years after the Iraq invasion of August 1990. Most of the ammunition used was Pakistani 1980 vintage 7.62x51 NATO caliber for the coaxial machine guns, and even after being buried in the Kuwait desert for more than two years, it all fired perfectly. The quantity was approximately 20,00o rounds per monthly training session, for four consecutive months.

Sealed ammo cans most likely. And, the desert is notably free of humidity. QED.