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August 25th, 2020

Smart Advice on Powder Storage — What You Need to Know

SUMMARY: Powder can have a very long shelf life. You need to watch for changes in smell and color. A reddish tinge, almost like rust on the powder, is a bad sign, as is a foul odor, not to be confused with a normal chemical smell. Either of these signs indicate it is time to dispose of your powder by means other than shooting.

Ever wondered about the stability of the propellants in your reloading room? There are some important things you should know about powder storage, to ensure consistent powder performance and safety. On its website, Western Powders (vendors of Accurate, Norma, and Ramshot powders) published an informative Q & A series entitled Dear Labby: Questions for our Ballistics Lab. Here are some excerpts that pertain to powder storage and shelf life. Worried that your powder may be too old? Western’s experts explain how to check your propellants for warning signs.

Proper Powder Storage

Q: I live in southern Arizona where it is very hot. I am told powders will become unstable if stored in an area not air-conditioned. My wife says no powder or primers in the house. Can powder be stored in a refrigerator? What about using a fireproof safe? I would appreciate your ideas. — M.C.

Lab Answer: SAAMI guidelines are pretty clear on issues of storage. They recommend storing smokeless powder in containers that will not allow pressure to build if the powder is ignited — ruling out gun safes and refrigerators.

CLICK HERE to Read SAAMI Guidelines for Powder Storage (PDF)

In their original containers smokeless powder’s lifespan is quite long, even in your hot, arid climate, typically longer than the average handloader would need to store them. Stored safely in a garage or outbuilding, your powder should last years. If you see the powder developing a reddish tint, or giving off a foul odor, it is time to discard it.

Clumps in Powder Container

Q: I ordered some of your Accurate 1680 powder back about in December. I just now opened it … and it is full of clumps. My knowledge tells me that means moisture. Am I wrong? I just now broke the seal and it has been stored in a ammo can with desiccant packs around it and a dehumidifier running 14-16 hours a day. I can’t imagine this being my fault, if this does indicate moisture. I don’t know if the pink part on the label is suppose to be red or not, but it is definitely pink, so if it was red I am wondering if I was shipped an old container? I hope that this isn’t bad and I am stuck with it…

Lab Answer: All powder contains a certain amount of moisture. When the powder is stored or during shipping, it can go through temperature cycles. During the cycling, the moisture can be pulled to the surface and cause clumping. Clumping can also be caused by static electricity if too dry or the powder has limited graphite content. You can break up the clumps before metering and they shouldn’t be a problem. This will not affect the powder performance, so your product is fine. Accurate 1680 labels are designed in Pink. As a side note, specification for testing powder is at 70° F and 60% humidity.

Shelf Life and Packaging Dates

Q: Does powder ever get to old to use and what identifying marks does your company put on the canister for when it is made, You have helped me out a while ago when I asked about keeping my cowboy shooting under 950 fps and it works great less stress on the hand and the recoil is very minimum. — R.B.

Lab Answer: On one pound bottles, the number is on the corner in a silver box. If the powder was poured today, it would read 012815 followed by a lot number. The whole number would look something like 012815749. Eight pound bottles have a sticker on the bottom with an obvious date code. The lot number appears above the date.

Western Powders Blog SAAMI Storage

Permalink - Articles, Bullets, Brass, Ammo, Reloading, Tech Tip 1 Comment »

August 6th, 2020

Guns and Ammo in Aftermath of Floods — What to Do

NSSF SAAMI flood flooding submersion water Ammunition Ammo damage
NOAA photo of flooding after Hurricane Floyd in 1999. The Colt Python Revolver once belonged to Elvis Presley (Rock Island Auction).

This past week, Tropical Storm Isaias has hammered the East Coast of the USA. The BBC reported: “From North Carolina up to New York, Isaias left more than 3.4 million residents without power. It spawned tornadoes, uprooted trees, damaged homes and caused floods and fires.” This article explains what to do if you have experienced flooding.

Firearms owners who have seen their guns and stored ammunition submerged by flood waters in storm-wracked areas are probably wondering if their firearms and ammunition can be salvaged and safely used. To answer these questions, the NSSF and the Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI®) created two documents outlining the proper response to submersion of guns and ammo. If you’ve got wet guns and/or ammo, download these two PDF files and read them carefully.

SAAMI Guidance 1: What to Do About Firearms That Have Been Submerged in Water

SAAMI Guidance 2: What to Do About Ammunition That Has Been Submerged in Water

Dealing with Firearms That Were Submerged

The SAAMI document “Guidance on Firearms That Have Been Submerged or Exposed to Extensive Amounts of Water” points out two major concerns about firearms that have been exposed to water: parts susceptible to moisture and rust damage such as metal parts, wood stocks and grips, and optics; and, secondly, infiltration of the action, barrel and safety systems by grit, silt and other foreign debris.

#1 Always unload firearms before beginning any treatment process.

It’s important to limit moisture and corrosion damage to the component parts of the firearm. This can be accomplished by disassembling the component parts and using up to two coats of a moisture-displacing lubricant such as Hoppes #9 MDL or WD-40 to clean and stabilize the parts while, importantly, following the product’s directions so as not to damage, for instance, plastic or synthetic parts. Another tip is to allow wood stocks and grips to air-dry and not be force dried by exposure to heat.

The document emphasizes that once the firearm has been thoroughly dried, consideration must be given to having the firearm inspected and serviced by the manufacturer, an authorized service center, or a qualified gunsmith before putting the firearm back in service.

Dealing with Ammunition That Was Submerged

NSSF SAAMI flood flooding submersion water Ammunition Ammo damage

Bottom Line, if your ammo has been submerged — DON’T USE IT. SAAMI explains why…

To help firearms owners determine what to do with ammunition that has been affected by water and moisture, SAAMI offers another helpful document, “Guidance on Ammunition That Has Been Submerged in Water.” This document covers differences in moisture resistance between centerfire, rimfire and shotshell ammunition, and potential hazards associated with “drying out” cartridges, including possible deterioration and damage to cartridges due to drying methods.

Another serious hazard that could result from using compromised ammunition is the potential for a bore obstruction due to partial ignition of either the priming compound or the propellant powder charge, or both. Firing a subsequent round through an obstructed barrel can result in bodily injury, death and property damage.

SAAMI provides the following cautionary conclusion: “It would be impossible to ascertain for certain the extent of the deteriorating affect, if any, the water may have had on each individual cartridge. Therefore, the safe answer is that no attempt be made to salvage or use submerged ammunition. The ammunition should be disposed of in a safe and responsible manner. Contact your local law enforcement agency for disposal instructions in your area.”

Permalink - Articles, Bullets, Brass, Ammo, Tech Tip 1 Comment »

October 26th, 2015

Tech Tip: Changes in Humidity Can Alter Powder Burn Rates

Tech Tip Norma Powder gunpowder moisture temperature humidity

We’ve all heard the old adage: “Keep your powder dry.” Well, tests by Norma have demonstrated that even normal environmental differences in humidity can affect the way powders burn, at least over the long term. In the Norma Reloading Manual, Sven-Eric Johansson, head of ballistics at Nexplo/Bofors, presents a very important discussion of water vapor absorption by powder. Johansson demonstrates that the same powder will burn at different rates depending on water content.

Powders Leave the Factory with 0.5 to 1.0% Water Content
Johansson explains that, as manufactured, most powders contain 0.5 to 1% of water by weight. (The relative humidity is “equilibrated” at 40-50% during the manufacturing process to maintain this 0.5-1% moisture content). Importantly, Johansson notes that powder exposed to moist air for a long time will absorb water, causing it to burn at a slower rate. On the other hand, long-term storage in a very dry environment reduces powder moisture content, so the powder burns at a faster rate. In addition, Johansson found that single-base powders are MORE sensitive to relative humidity than are double-base powders (which contain nitroglycerine).

Tests Show Burn Rates Vary with Water Content
In his review of the Norma Manual, Fred Barker notes: “Johansson gives twelve (eye-opening) plots of the velocities and pressures obtained on firing several popular cartridges with dehydrated, normal and hydrated Norma powders (from #200 to MRP). He also gives results on loaded .30-06 and .38 Special cartridges stored for 663 to 683 days in relative humidities of 20% and 86%. So Johansson’s advice is to keep powders tightly capped in their factory containers, and to minimize their exposure to dry or humid air.”

Confirming Johansson’s findings that storage conditions can alter burn rates, Barker observes: “I have about 10 pounds of WWII 4831 powder that has been stored in dry (about 20% RH) Colorado air for more than 60 years. It now burns about like IMR 3031.”

What does this teach us? First, all powders start out with a small, but chemically important, amount of water content. Second, a powder’s water content can change over time, depending on where and how the powder is stored. Third, the water content of your powder DOES make a difference in how it burns, particularly for single-base powders. For example, over a period of time, a powder used (and then recapped) in the hot, dry Southwest will probably behave differently than the same powder used in the humid Southeast.

Reloaders are advised to keep these things in mind. If you want to maintain your powders’ “as manufactured” burn rate, it is wise to head Johannson’s recommendation to keep your powders tightly capped when you’re not actually dispensing charges and avoid exposing your powder to very dry or very humid conditions. The Norma Reloading Manual is available from Amazon.com.

Real-World Example — “Dry” H4831sc Runs Hotter

Robert Whitley agrees that the burn rate of the powder varies with the humidity it absorbs. Robert writes: “I had an 8-lb. jug of H4831SC I kept in my detached garage (it can be humid there). 43.5-44.0 gr of this was superbly accurate with the 115 Bergers out of my 6mm Super X. I got tired of bringing it in and out of the garage to my house for reloading so I brought and kept the jug in my reloading room (a dehumidified room in my house) and after a few weeks I loaded up 43.5 gr, went to a match and it shot awful. I could not figure out what was going on until I put that load back over the chronograph and figured out it was going a good bit faster than before and the load was out of the “sweet spot” (42.5 – 43.0 gr was the max I could load and keep it accurate when it was stored in less humid air). I put the jug back in the garage for a few weeks and I now am back to loading 43.5 – 44.0 gr and it shoots great again. I have seen this with other powders too.”

If you have two jugs of the same powder, one kept in a room in your house and one somewhere else where it is drier or more humid, don’t expect the two jugs of the same lot of powder to chrono the same with the same charge weights unless and until they are both stored long enough in the same place to equalize again.

Permalink Reloading, Tech Tip 7 Comments »

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