Accuracy: A general definition for this term that covers the objective aspect is, "to achieve with consistent repeatability the coincidence of bullet impact with the rifle's point of aim". The three sets of variables that influence accuracy are: 1) the rifle, 2) the ammunition and 3) the shooter. The rifle, to achieve its potential capability should have its action trued and accurized. Then if a premium match grade rebarrelling job isn't in the budget at least have the action glassbedded and barrel free-floated. A trigger adjustment is worth the typical cost. If your "out of the box" rifle shot between 1" and 2" groups, it should now be shooting lid" or so, groups at 100 yards.
To illustrate the value these accuracy improvement recommendations can have, the following example says it all:
Steve Bush is a Special Forces sniper and also a long-range and Palma competitor. He sent us his .308 chambered competition rifle for accurizing as he could only get groups at 300 yards. Arnold Arms performed the accuracy steps outlined above. Steve phoned us to report after getting his rifle back that, he now was getting "one ragged hole with 5 shot groups at 600 yards" and using Palma peep sights! That's better shooting than most of us can do using a scope, but it illustrates vividly what results are possible after accurizing work is performed on a rifle!
Quality ammunition is very important in contributing to accuracy and precision handloads fired in hunting rifles can approach benchrest accuracy. Bullet manufacturers today, offer tolerance levels of .1 grain wte. & .0003" jacket wall thickness consistency not available twenty years ago in hunting bullets that are almost as good as match grade one's. Besides quality bullets and stringent cartridge manufacturing standards, bullet seating depth, as mentioned earlier, is very important for optimum accuracy. Factory loads maintain a range of over-all-cartridge length (OAL) which meets an average standard set by the industry. This however may or may not be the optimum OAL for your individual rifle (and usually isn't). An example of this is the 7mm Rem. magnum's industry standard of 3.24" OAL. Many rifles so chambered, shoot best at 3.27" OAL when shooting 150 gr. Nosler ballistic tips or partitions. Only precision made handloads "tuned" to your rifle will get you maximum results. Different bullet makes, shapes, weights and dimensions require different ideal seating depths to find the "sweet spot" where it all comes together in an individual rifle.
The third variable is the shooter and techniques they can use that will promote good form and consistent shot placement. Proper hold, support, maintaining point-of-aim and trigger squeeze all affect results. While books have been written on the subjectand videos are available from several sources, one can also inquire at their local gun range or shooting club for more personalized instructional assistance. A simple test we all can do at the range is to aim and "dry-fire" at a target several times. See if the crosshairs stay on the same point of aim after firing versus before. Practice until they do!

Barrel and Action Maintenance: A new rifle needs to be thoroughly cleaned and inspected as well as, checked for proper functioning before ever taking to the range. What are the proper cleaning intervals during or after shooting sessions? A new rifle or newly rebarrelled one, should have its bore cleaned after every shot for the first ten shots. (Then after every five shots until 40 to 60 rounds have been fired through it for initial break-in.) Subsequent cleaning intervals during a session at the range should be practiced after every ten to fifteen rounds fired and not greater than twenty rounds. If this cleaning frequency is not maintained, both accuracy and barrel life will diminish. Note where your first and second shots hit on the target following cleaning versus third, fourth and fifth shots. (Remember to let barrel cool down 3 to 5 minutes or more between shots.) Most rifles after cleaning, will "print" differently on paper the first shot or two versus how and where the 3rd through 5th shots group. This is due to a slight difference in velocity and pressure the bullets experience between a thoroughly cleaned barrel and after slight fouling is present. A suggestion that you may wish to incorporate is to sight-in your rifle making adjustments to scope, based on where the 3rd through 5th shots group. Then clean your rifle and put two "fouling" shots through it before taking it hunting. If you don't choose to do the fouling shots trick, then thoroughly dry patch bore to remove any excess oil or solvents before going afield.

Barrel Throat Erosion: The greatest single factor contributing to throat erosion and subsequent loss of accuracy is excessive heat caused by extended shooting with a hot barrel. When normal load development testing or sighting-in before hunting is conducted, allowing the barrel to cool down between shots is number one in promoting normal barrel life. (It also reproduces field conditions of hunting with a cold barrel.) Secondly, proper maintenance and regular cleaning intervals with a good quality copper solvent and patches is essential for maintaining accuracy and barrel life. All barrels foul due to burnt powder related particles and traces of copper gilding from the bullets and their engraving by the lands when fired. Velocity and bullet friction have little effect on barrel wear and are often blamed in error as the culprits. Twist rate has also mistakenly been confused with contributing to barrel wear. Twist rate relates to bullet size (wte.) diameter, length and velocity for stabilization.

Barrel Life, What's "Normal?": This is going to have to be a two-fold definition because of the realities of several shooting and hunting disciplines. First, are the precision shooters - competition/match, ranging from benchrest to 1000 yard contests and similar to them are the ardent varmint hunters. More often than not, they will put hundreds of rounds through their rifles in a weekend. Both cooling down periods and maintenance intervals cannot always be practiced when one is trying to win a match within the specified time intervals allowed or reducing the rampant prairie dog populations that exist in many parts of the country.Barrel life may only be as long as a few thousand rounds (2,500 - 5,000) when participating in these activities. Most avid practitioners use two rifles for such typical extended shooting sessions. The remaining shooters and hunters, who fire their rifles considerably less often than those described above, should realize an average barrel life of 8,000 to 10,000 rounds. Again, not shooting with a hot barrel, proper maintenance and cleaning intervals will enhance barrel life

Belted vs. Non-Belted Cases: Some ammunition lines marketed today state that a non-belted cartridge case is inherently more accurate than a belted one. In reality, neither one is more accurate than the other! To explain this statement, one has to understand how the two types of cartridges perform in a chamber before, during and after firing. In addition, let's ask, what precision handload techniques could be done to either type of cartridge that would promote maximum potential accuracy? First to consider is, how do cases headspace in a chamber. Any non-belted rimless cartridge (excluding rimmed cases such as .22 LR or 30-30's) headspaces on the shoulder to neck/shoulder junction portion of the case and the bolt face. Headspace is the measured distance, in thousandth's of an inch, between the bolt face and that part of the chamber that stops the cartridge's forward movement in the chamber. So in non-belted "rimless" cases it's measured from the bolt face to the mid-point of the chamber's shoulder angle relief cut in the chamber. "GO/NO GO" gauges are generally used to determine if a chamber's headspace is within industry tolerance. A "belted" magnum case's headspace is measured from the bolt face to the forward edge of the belt, as this is the point of contact that stops its forward movement in the chamber. Neither type of cartridge contacts both points sunultaneously (bolt face and forward stopping point in the chamber) until the cartridge is fired. Otherwise, you'd have no headspace to begin with. During the "moment" of firing, the case first moves forward from the firing pin's forward thrust until each case contacts the respective stopping point in their chambers. Upon ignition, the extreme pressure from expanding gas in the cases cause both types to enlarge in their chambers until they press against the chamber walls. At the same instant, the primer is partially backed out of its pocket until the pressure forces at work, push the case back against the bolt face, reseating the primer in the process. This movement in either type case is just a few thousandth's of an inch and the entire sequence occurs in a millisecond. As both the chamber's cylindrical walls stop the case body's expansion and the bolt face/breech stop the rearward movement, all that's left is the cork in the bottle (bullet) to move down and out the barrel allowing the pressure to dissipate. Without this escape route (barrel) you'd literally have a bomb in your hands when you fired any firearm. (Pressure generated typically runs 45,000 to 60,000 psi in the chamber and could ruin your day if these forces aren't respected.) Pressure also pushes the shoulder area on both types of cases forward against that region of the chamber wall. This occurs before the bullet leaves the case mouth. The neck also expands out against it's chamber wall, centering the bullet. Following pressure dissipation the case contracts a thousandths of an inch or so, allowing extraction to occur. Now that you understand what happens to either type of cartridge before, during and after firing, let's look at accuracy variables that could affect one or the other. As already explained in 'Pressision Handloading Steps' which, one can perform to achieve optimum accuracy from a cartridge - all steps and principles fully apply to both types of cases. Taking "fire-formed" cases and following the steps outlined in developing precision handloads and then firing them in their respective rifles will give identical results for accuracy, if all other variables remain the same. A further point could be argued if one chose to, that a belted magnum actually contacts four points in the chamber during the firing process while the non-belted contacts three. These points are: 1) the forward edge of the belt, 2) the chamber wall, 3) the bolt face and, 4) the shoulder/neck region in a fire-formed case. The non-belted ease only makes contact with points 2, 3, and 4 when fired, even when using a fire-formed case. All cartridge cases in relation to their chamber dimensions have .002" to .006" clearance, otherwise cases wouldn't feed nor extract before or after firing. There's many benchrest shooters out there that work with minimum chamber-to-cartridge tolerances and have experienced stuck cases because of "tight" fit. Because of the standard chamber tolerance allowance in any rifle, the influence of gravity when holding the rifle horizontally for firing, will cause any cartridge to lie .0005" to .0015" low in relation to the chamber's longitudinal center line axis. As the case expands out against the chamber wall upon firing, the bullet becomes more "centered" before it leaves the case mouth and fully engages the lands. A fire-formed case from any particular rifle when "neck-sized" only will provide a closer chamber fit and bullet centering to the bore alignment for improved accuracy. The more "trued" the receiver, bolt, lugs, chamber and barrel are, as well as barreled-action fit to the stock is, the more accurate the rifle will shoot, period! That's what is called "accurizing and truing the action". Correct reamer chambering and using a match grade quality barrel and tuning the trigger to remove creep or excessive poundage are further steps one can do to enhance accuracy. Boattail vs. Flat-bottom Bullets: More matches have been won over the past 40 years with boattail bullets than any other kind. Military rifle cartridges are all loaded with boattail bullets. Nosier ballistic tips and Sierra boattails are excellent hunting bullets providing benchrest type accuracy. Because of bullet jacket thinness the ballistic tips should be limited to deer size game. A myth that still exists is, boattail bullets will cause throat erosion earlier than flatbottom bullets. From government test results (Frankford Arsenal) and those conducted by manufacturers, accuracy will improve and be maintained up to 10,000 rounds using boattail bullets with proper cleaning, while flat-bottom bullet accuracy peaked at around 2,000 rounds and started to diminish by 5,000 rounds.

Distance to Target: Knowing bullet drop at various distances for your particular load, as well as distance to game if your hunting, is as important as having your rifle sighted-in before hunting. Using the same rifle and ammo combination cited in the example 'Uphill and Downhill Shooting' (next page) let's look at some typical bullet drop-to-distance facts. If you're sights put the bullet's impact dead-center at 100 yards, it will drop about 2.8" at 200 yards, l l" at 300 yards, 25" at 400 yards and 46.5" at 500 yards. If you choose to set your sights for a 200 yard zero (1.4" high at 100 yards) your 300 yard drop will be 6.6" and just over 19" at 400 yards.
Getting familiar with distances to your target or potential game locations can be established while you wait for old mr. buck to show up. One of the best tools for this is a range finder. Picking different points of reference, first estimate distance, then find out actual with the range finder. This will help in practicing "eye-ball" range estimating as well as determining actual distance before your game appears. You can then put the instrument in your day-pack after determining the different distances you selected to check until you move to a new location. Keeping a few notes on distances from each location, for future reference, can be of help later.

External Ballistics: These consist of those variables that have potential for influencing the bullet's flight path once it leaves the rifle's bore. Another influence on the bullet's departure is barrel whip and vibration caused by the forces and pressure from the cartridge firing and bullet's travel down the bore. A "thin" featherweight barrel whips more than a thicker and stiffer barrel, which the latter will hold to a tighter group. A properly finished muzzle crown is the last point of influence on the bullet's departure. Wind, distance, humidity, elevation, and temperature will all have an influence on a bullet's eventual point of impact. Understanding and allowing for wind and distance are the two factors that have the greatest influence on point of impact. Most reloading books offer charts that illustrate bullet drop at various ranges and drift due to wind velocity and angle.

Fluted vs. Standard Barrels: Fluting a barrel reduces its weight a few ounces and provides a unique streamlined appearance. Beyond those two attributes, a fluted barrel doesn't do much. As far as strengthening a barrel by having it fluted, is more marketing hype than actual improvement. Barrel manufacturers require one to use a #5 or #6 contour barrel or larger if you flute it, as the strength minimum standards for thickness in fluted grooves must be maintained. Fluting a #3, or # 4 contour barrel reduces the stiffness, minimum strength level and may cause unwanted harmonic whip or flex. Longitudinal strength isn't the important point, the strength of the cylindrical wall is, however. (Sniper and competition rifles are usually not fluted.) · Rarely will you see a competitive benchrest shooter with a fluted barrel, and there's probably a good reason or two for that. If cooling your barrel is a major concern, then you can choose one, but unless you're needing to cool down a machine-gun barrel after firing 50 to 100 rounds it doesn't do much for most of us!

Muzzle Brakes: There are several quality muzzle brakes on the market today. If you're recoil sensitive, have a bum shoulder, dangerous game hunt or shoot alot, then a muzzle brake may be a good choice. Having a thread protector also with it is worthwhile. Most people use the muzzle brake for "sighting-in", then fine tune with it off as they typically hunt with it off. Dangerous game hunters that choose to use one, do so, as it allows them to keep the game in their scope under recoil for a fast follow up shot if necessary. Varmint hunters sometimes use a muzzle brake, so they can see the red mist fly through their scope. A muzzle brake will reduce recoil 30% to 40% and can increase shooting pleasure as long as, good ear protection is worn.

Uphill and Downhill Shooting: This may be one of the most frequent causes of missed shots on game. While there is only a slight difference between uphill and downhill shooting due to gravity, it can be ignored for hunting. The key point to be made is, it's not the up or downhill distance to your game that's important, but the horizontal distance between your position and the game's position. Visualize a right triangle, the shooter is at the top point and your game is out at the horizontal point. It's not the distance of the longer angular line connecting these two points that determines bullet flight (drop) to target, but the base horizontal line distance does. To illustrate this further, imagine your game is in a draw 400 yards down the hillside from your position. The actual horizontal distance though is only l SO yards out. Your bullet (150 gr. in a 7mm may) leaves the muzzle at around 3,050 f.p.s. and you're sighted dead-on at 100 yards. Bullet drop is approximately 25" at 400 yards with the 150 gr. bullet combination described above. While the actual drop in the bullet's flight due to horizontal distance to your game is only going to be about 1.5"! Understanding these variables and adjusting for them will help you put that trophy on your den wall rather than someone else's. 

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