Preparing Hunting Season Loads

The question your asking is a legitimate concern for reloaders that load their hunting ammo however in most cases the effect will be negligible. If we consider the fact that the highest percentage of shots taken at WT deer the most prevalent species of big game in north America will be well on the shy side of 100 yards then it becomes apparent that variations in ballistic uniformity will have only a small effect on ballistic performance both in accuracy and in terminal performance.

When the distance for the shot becomes long then internal ballistics become more critical as to accuracy, trajectory, and terminal ballistics. There are charts available on line to help determine velocity loss with temperature drop from the temp the load was developed at. Those are helpful in calculating trajectory but not conclusive. This because a velocity change due to temp change may also change the zero of the rifle so only allowing for a velocity loss may not be adequate to calculate trajectory. It may also require a re-zero of the rifle then re-calculate with the adjusted velocity loss.

As for terminal performance most projectiles will have a preferred performance velocity range and a velocity drop due to temp will likely never put you out of that performance range unless your load was barely at its edge to begin with or that the temp change was so extreme like as if the load was developed in death valley at 130* F then used in Antartica at -130*F so possible but not likely.

One way to help to reduce velocity variations due to temp change is to load with the newly developed powders that are specifically designed for that purpose to be less temperature sensitive than are many of the older powder developments. Some of the newer powders designed to reduce velocity/pressure changes with temp changes as well as containing fouling inhibitors are truly impressive and that applies to both jacketed and lead alloy bullets. Makes me wonder how we ever got along so well without them. I still have a lot of old powders that I will continue to use but I am not so closed minded that I will refuse to accept the inherent superiority of these newer powders. Its easy to just keep doing the same thing the same way all the time but there is little to gain from that. If we as loaders have done well in the past developing good loads with the powders then available but are now willing to keep up the same type of work that got us there we have nothing to loose but perhaps much to gain.

I as a cast bullet shooter am particularly interested in the developments in fouling control type powders. These powders are of course being developed for high power shooters and high volumes of fire but the developments are not specific to one type of metal fouling and should apply to lead alloy fouling as well as guilding metal fouling and copper. There is always room for improvements in my shooting so I look at these new developments with great interest.

Rob my good friend it has occurred to me that at times in trying to adequately answer your questions I may seem to be condescending and if I come off that way I am sorry and apologize for it. I know you well Rob so know that most of what I answer you already know. What I attempt to do with answering any questions is to aim for the center of a wide audience so that folks with many different levels of experience might find something useful in my answer. So please understand when I attempt to answer a question I am not speaking to the questioner alone but to many that may gain something from the answer.

Sometimes I read back through my answers and think wow what a snob that wrote that. My intent is never to prove anything but always to share what I have spent a lifetime learning and continue to learn. I , we are getting old and if not shared now will take our knowledge with us when we leave for home. Something I have learned in my quest for knowledge in guns and shooting is that what was once common knowledge on this subject was passed over and left behind with new developments. When that happens it seems hard to re-learn it as many of us have had to do attempting to extract the best performance from our obsolete black powder arms weather muzzleloading or cartridge.

Us now being the old timers to the newer generations of shooters kind of have an obligation to propagate the knowledge we have gained in our lifetime. It seems such a shame to have it lost once again to time.