Before you get the idea that an article about sensitivity should be aired on Oprah, let me say two things:
1) Ammunition can be sensitive to a lot of environmental factors.
2) No one I know cares in the least what Oprah and her friends think on this subject or any other.
We handloaders, especially those of us that use those handloads for hunting, expect a great deal from our ammunition. We expect our firearms to function with this ammunition in a wide variety of conditions, we expect it to be consistent in accuracy under widely different temperature and altitude situations and we expect it to hold up to the neglect of poor storage and handling.
It is easy to forget, in the warm and calm handloading room, that we may be depending on that cartridge on some wind- and snow-swept ridge, soaking wet or so cold the brass sticks to the fingers, or near the equator where day and night temperatures may vary by 50 degrees and condensation forms so fast gunmetal will rust right before your eyes.
For me, a round that doesn’t go bang when it is supposed to can define heartbreak and disappointment. There are enough duds in the world and we don't need to be making more of them.
When we handload we must start with quality components. This is not to say that surplus brass is to be ignored, or that bulk bullets are a bad thing (they most certainly are not) but whatever we start with, it must be in the best possible condition.
This means components must be clean and inspected and primers and powders must come from proper storage. My system is about as simple as it gets: if I have any doubt about a component, it gets cut from the roster.
For lead bullets, it's easy; they go back in the pot for the next casting. For cases, they must be segregated by brand and within brand by the number of times fired. For my hunting I do not use cases that have been loaded and fired more than three times; the older cases are used for practice rounds.
Powder and primers are usually not a problem; both are used up pretty quickly and not stored for long periods of time. The point is to start right and so you will be glad later.
Moisture is the big fish in the list of ammunition enemies. Any duck hunter can tell you of hunts gone to hell because he left his shells in a bucket stool overnight or allowed them to be splashed or sat on by a dripping retriever.
Rifle ammunition can be ruined just as quickly. Left in a hunting coat pocket after a foul-weather hunt, and then taken from a warm house into the frigid woods and then back again, these mistreated rounds can slurp up enough moisture in the form of condensation – even a tiny drop –to render them inert.
The area around the primer is most often the culprit but banded bullets can also create a space between bullet and case neck that will hold enough dampness to ruin your day. A hang fire can be worse than a misfire and either can come from moisture getting into your ammo.
Altitude is something most hunters ignore when it comes to ammo performance. We all know that changes in atmospheric pressure can change external ballistics, but to what degree is the question. When I lived in Gloucester, Virginia, elevation 12 feet above sea level, and loaded ammunition for hunting, then took that ammunition to Buck Mountain, nearly 5,000 feet higher, the bullets did some amazing things on the target range.
Suddenly my groups were significantly higher above zero with some calibers and loads. At the higher elevation, the decreased pressure and thinner atmosphere acted to reduce drag and change the trajectory. I attempted to determine if there were any velocity changes by taking chronograph readings at sea level and at the higher elevation using 10-shot strings of four different calibers both at the muzzle and at 200 yards.
What I found was that initial velocities were virtually the same but the 200-yard readings were statistically different, with the higher elevation numbers coming in faster than those shot at sea level. The larger caliber, heavier bullets seemed to suffer more than the lighter bullets of smaller diameter, but both (.35 Whelen, 250-grain Hornady and 6mm Remington 87-grain Hornady) showed percent velocity changes that could be measured. All tested ammunition retained more velocity at higher elevation than that which was measured at low elevation.
So, if you live at sea level or thereabouts and plan to hunt the Colorado high country above 10,000 feet you need to check your zero when you get to your hunting destination.
It’s common sense that ammunition is temperature-sensitive. Ammunition left to bake on the dashboard can reach temperatures approaching 120 degrees in a closed car or truck. Ammunition left in the car on a frigid night can assume air temperature. If that temperature is low enough it can surely cause changes to ignition and pressure.
Going back and forth between high and low temperature extremes will, as mentioned, cause condensation to occur within the cartridge case. Here you have to use your best judgment and care with your hard-earned handloads. If you store your ammo over long periods of time do your best to keep the temperature of storage constant.
And remember, if one round is bad, chances are others in that bunch are likewise affected. Be smart, care for your ammo and it will consistently get the job done.
Whether you choose to reload because it's a more cost-effective alternative, or you're interested in creating custom ammunition, it's important to know what you're doing. Done incorrectly, handloading can be risky, but with the appropriate tools, equipment, and techniques, it can be a more than viable alternative to purchasing manufactured ammunition. With the Reloading Ultimate Collection, discover the best practices for reloading ammo for rifles, handguns, and shotguns. Load up now