2009 FULLBORE Update - Nook
Although somewhat dated at this point in time, this article provides detailed performance assessment of 8 different .30 caliber bullets weighing under 156 grains (the international weight limit according to FULLBORE rules). This analysis includes the ‘new’ Sierra Palma bullet (2156) as well as the Berger 155.5 grain FULLBORE bullets which are primarily used in modern FULLBORE competition.
300 Winchester Magnum vs. 338 Lapua Magnum WEZ Analysis - Nook
The specific intent of this WEZ report is to compare the ballistic performance of the 300 Winchester Magnum to the 338 Lapua Magnum with several available ammunition types. Understanding how these weapons compare in terms of hit percentage is important in the context of modern military applications. The recent upgrade of the M24 to the more modern XM-2010 platform would indicate that the 300 Win Mag is here to stay.
300 Winchester Magnum WEZ Analysis - Nook
The 300 Winchester Magnum is a well established cartridge in the US arsenal. Recent modernization initiatives focused around rifles and ammunition are advancing the effectiveness of this proven cartridge. This Weapon Employment Zone (WEZ) analysis [REF 1] is intended to quantify how the hit percentage of the 300 Winchester Magnum is improved thru these modernization efforts. Primarily the ballistic performance of various ammunition types will be evaluated.
7mm VLD Analysis: Part 1 - Nook
Berger currently offers two bullets in 7mm: 168 grain and 180 grain VLD’s. The versatility of these two bullets extends from big game hunting to long range benchrest competition and everything in between including long range NRA prone and F-class score shooting. The 7mm 180 grain VLD is of particular interest because of its stellar advertised BC. In part 1 of this two part series, I’ll describe the ballistic properties and performance of these two bullets in a general sense, meaning the information applies to all types of shooting that these bullets might be used for. In part 2, I’ll explore the ballistic properties and performance of the two bullets from the perspective of long range NRA prone slow fire competition.
7mm VLD Analysis: Part 2 - Nook
Part 1 of this series focused on the fundamental design, stability characteristics, and Ballistic Coefficient testing results of Berger’s 7mm bullets, both the 168 grain VLD and 180 grain VLD. This month, I’ll be focusing on the analysis of those results, specifically in the context of NRA Long Range (1000 yard) slow fire prone competition. The focus of the performance analysis will be on the wind drift comparison between these two bullets.
Ballistics Coefficient Testing - Nook
All serious long range shooters are aware that bullets have a ballistic coefficient, and that it’s somehow related to how much the bullet will drop and drift in the wind. Shooters place various degrees of importance on knowing the exact BC of their bullets, and shooting bullets with high BC’s. In this paper, I want to explore some of the benefits of knowing precisely what the BC of their bullet is, and also, the different methods available to determine the BC of a bullet. The main point of this writing is to show that BC’s can be measured from firing tests more easily, and with less error than is commonly thought.
BC Testing: Berger .30 cal 155 Grain VLD - Nook
The purpose of this article is to discuss the ballistics of the Berger .30 caliber 155 grain VLD as measured by firing tests. Such thorough and precise firing tests are a rare commodity for the sporting arms industry. As tempting as it is to dive into the interesting topic of the test itself, only limited discussion is
provided on the actual test procedures. The main focus will be on the results of the tests.
BC Testing: Lapua .30 cal 155 grain Scenar - Nook
Take a detailed look at Lapua’s flagship FULLBORE bullet, the 155 grain Scenar. This report details the physical properties of this bullet including mass and aerodynamic properties, as well as ballistic performance as determined by live fire testing.
BC Testing: Sierra .30 cal 155 Grain - Nook
Somewhat of a historical article at this point in time (2013), this article takes an in depth look at what was once the standard bullet for international Palma bullet shooting. This detailed article describes the careful testing and ballistic performance assessment of this classic bullet.
Epicyclic Swerve - Nook
This work was done to investigate a question about the grouping ability of rifles at various ranges. Many shooters, including myself, have observed the strange phenomenon of a rifle that groups angularly smaller at long range than short range. In other words, a rifle that groups 1” at 100 yards grouping 1.5” at 200 yards (you would expect no less than 2” at 200 yards).
Extending the Max Effective Range of Small Arms - Nook
This article is an extension of the previous article (Max Effective Range of Small Arms). The first objective is to show how the hit probability diminishes as the Maximum Effective Range (MER) is exceeded. Furthermore, ideas are presented for how to increase in maximum effective range by understanding and applying corrections for so called ì6 degree of freedom effects.
Gyroscopic (Spin) Drift and Coriolis Effect - Nook
Most long range shooters are aware of the effects of gravity, air resistance (drag) and wind on their bullets trajectory. There are many commercial ballistics programs on the market that do a fine job of predicting trajectories which only account for gravity, drag and wind. Gravity drag and wind are the major forces acting on a bullet in flight, but they’re not the only forces. In this article, I’ll explain some of the more subtle forces that influence the path that bullets take.
How External Ballistics Programs Work - Nook
There are several possible methods for calculating the flight path and other properties of a ballistic trajectory like: velocity, time of flight and wind drift. Some programs calculate more things than others. Some have the potential to be inherently more accurate than others. In this article, I’ll try to explain the features of each method.
Max Effective Range of Small Arms - Nook
In this article, I'll attempt to define a method for finding the maximum
effective range of a shooting system under the influence of predefined
field variables. This is accomplished using a 6-degree-of-freedom (6
dof) computer simulation that is able to model real world factors
influencing the rotation and translation of spin stabilized projectiles.
I'll then show how the results can be used to make decisions about what
type of rifle is right for a particular application, and how far a weapon may be successfully employed against specific targets.
Practical Ballistics - Nook
External ballistics is the science of bullet flight, and is part of the diverse skill set required to hit targets at long range. When science is applied in the real world, especially in a field environment, compromises are a necessary evil; perfect data just isn't available. How much the compromise affects your ability to hit targets will depend on your tools, and more importantly, your knowledge of how to use them properly. This article will explore the application of external ballistics to tactical shooting scenarios, focusing on how to close the gap between pure science, and practical application.
Probabalistic WEZ - Nook
This paper outlines a method for systematic and comparative evaluation of small arms performance in various shooting applications. The Weapon Employment Zone (WEZ) analysis presented here is model based, and statistical in nature. The objective is to quantify the hit percentage for a given weapon system against a specific target as a function of range, considering the uncertainties involved in field shooting.
Understanding Long Range Bullets Part 1 - Nook
When you look at the bullets we use for long range shooting, you can’t help but notice the striking similarity between all of them. From .224 thru .30 caliber, they have just about the same proportions. In this article, Iíll try to explain the major consequences that scale has on long range bullets. This is the first installment of a two part article. This part establishes some facts about bullet scaling, and the second article examines how you can use the information to make better-informed decisions about your equipment.
Understanding Long Range Bullets: Part 2 - Nook
In part one of this series, we identified some basic trends that occur when you scale bullets up and down in caliber. Most of our findings were Fundamental and academic. This month, I want to take a close look at some of the practical consequences of scale. Whereas last months article focused on establishing facts, this part will give some conclusions, judgments and some of my opinions based on the facts.
What's Wrong with .30 Cal - Nook
In recent years, long range shooting has evolved in many ways. One of
the major trends is towards smaller calibers. Calibers as small as 6mm,
and even .224” are commonly being used in 600 and 1000 yard prone and
Benchrest competition. In spite of the once common knowledge that
„bigger is better‟ for long range shooting, the „benchmark‟ has shrunk
from the big .30 cal magnums to the more moderate 6.5mm. Long range
championships are being won with the tiny 6mmBR once thought
underpowered for all but short range Benchrest competition. Why is this?
Why is the once venerated .30 caliber loosing so much ground to the
smaller calibers for long range shooting? Recoil, of course, plays a
major role, but that‟s not all there is to it.