ES Standard Deviation. TMJ 63 HP 74 HPBT 36 Open Tip Match 52 What is Ballistic Coefficient? The more streamlined a projectile, the better it cuts through the air. Typically expressed as a ratio, the higher the BC, the more efficiently it cuts through the air on its way to the target. More aerodynamic projectiles will be more consistently accurate and have a larger BC.
This is why some of the above ammunition performed better on target despite large variations in velocity. The BC of a bullet design will greatly affect precision, especially at ranges beyond yards. If you take a look at the most precise groups we had at yards, most featured projectiles with a boat tail hollow point design.
This design is well-known for resisting drag and delivering consistent long-range accuracy. The exception to this in our test data was the Federal Gold Medal. It is possible that the small sampling of data or shooter fatigue contributed to the poor results we recorded. A larger sampling could conceivably disprove our findings. Interestingly, the loads with the lowest standard deviation and therefore most consistent velocity in our test group were Winchester Match HPBT.
This was the clear winner with an average group of just 1. We are officially declaring the Prvi Partizan the winner of our small test group in. Who would have thought it, right? Otherwise, we should have recorded better numbers from the Federal Gold Medal loads. Like so many things in the world of shooting, there is no clear cut answer. After all, ammo is just a tool and some tools are better suited for some jobs than they are for others.
For competition shooting, where repeatable precision accuracy is essential for high scores, you need high quality ammunition. Even the smallest variances can have a huge impact on your final score. True match grade quality ammunition is crucial for success in these highly competitive arenas. Law enforcement and military snipers also require surgical precision when it comes to their ammo. Lives depend on accurate shots, often at extreme distances where the slightest fluctuation in performance could have disastrous consequences.
If you are an amateur recreational long-range shooter who gets a major thrill out of busting bulls-eyes, you might be willing to fork out the extra cash to fund your hobby. The needs of the average hunter or recreational shooter are easily met with less expensive ammunition, so long as they choose loads that are reasonably reliable and accurate. It is often used as a marketing tool to get shooters to spend more money without producing measurably better results.
And if you want true precision ammunition, you can always load your own. Not all firearms are created equal.
Just like match grade ammo is supposedly manufactured to exacting tolerances, competition firearms are designed to be just as precise. You may get magnificent performance out of some firearms, while you may only achieve mediocrity with others no matter what ammo you feed it. This basically means that military match ammo is designed from the ground up instead of being a modification of an existing load or just cherry-picked cartridges.
So just how much more accurate are match rounds compared to their standard counterparts? Granted, these are only the minimum accuracy standards and I can say from experience that the M round will greatly exceed those criteria, but it does provide a baseline for just how much more accurate match ammunition can be than standard ammo.
The lot number can usually be found on the exterior of the box or case that the ammunition shipped in. We hope you found this article informative. Be sure to let us know your favorite match cartridge or bullet in the comments! Feb, 26, Mar. The powder or propellant used in your ammunition creates a large volume of gas at high pressure, the rate and volume at which this gas expands determines the muzzle velocity of your bullet.
Some powders burn faster than others, and some powders have greater variations than others, and as you might have guessed, those variations will cause the inconsistency that ruins your accuracy. I learned a lesson the hard way once when I loaded a fairly unstable powder to max pressure, months later in the heat of summer that load would be dangerously hot. Temperature can affect the way powders burn, as does the humidity. Match grade ammunition should use the best powders available that are temperature stable, and consistent burn rates from one lot to another.
For comparison, I have seen ammunition vary twice that much shot to shot at room temp. Handloaders know the value of good quality primers, in the current shortage, finding good primers in any large quantity feels like getting away with a crime.
The primer creates the spark that ignites the powder inside the cartridge, some primers create a hotter or bigger spark than others.
Good primers create a uniform ignition reaction every time. Matching a good primer to the appropriate powder charge is a large portion of creating that perfect gas pressure curve, the one your rifle needs to make consistent and accurate shots. Using the best and most consistent components, properly assembled can provide extremely accurate ammunition. In order to illustrate the practical differences between match-grade and non-match-grade ammunition, I directly compared each component part of two popular loads to demonstrate an age-old rule: consistent ammunition equals ammunition that performs.
Before we get into the specific numbers for the loads I compared, there are a few technical points that need to be defined and explained. While they may be at times used interchangeably both here and elsewhere , the true meanings are quite different.
Precision: Pertains to the closeness of shots relative to one another. Putting 10 shots into less than an inch at yards would be considered high precision. Accuracy: Pertains to the closeness of shots relative to your intended target.
The key takeaway: Precision is independent of accuracy. This makes sense if we think about it. And your average lever gun shoots in the 3 to 6 MOA range, but the fact that they kill thousands of deer every hunting season shows they are accurate rifles with a suitable level of precision.
Much of accuracy is target-size dependent. Each of these components plays an important role in the potential precision of a cartridge. And in our two test loads, the quality of these parts is with the possible exception of primers fortunately very comparable. Both loads are in Winchester. There is some debate on whether on not match grade primers matter, and what makes them different from regular primers. ZQI does seal their primers in the case with a green liquid sealant after installation, and they are crimped in place according to NATO specifications.
The Hornady primers are simply pressed in without any sealant or crimping. Quality brass in match-grade ammunition is important for a variety of reasons. And when it comes to the overall precision of the ammunition, this component plays a major role. Brass is the combustion chamber in which the powder is ignited. When I prepped the cases, I performed the following steps:. This is the bare minimum required to process brass cases for reloading.
These actions render the outside dimensions of the cases to be, for all practical purposes, identical. So, any weight variations mean that the internal volumes of the cases are the variable in play.
0コメント