Getting started in Precision Rifle Shooting. (Guide)

[fyaman43]

Great read and good to revisit.

 

[Boomslang57]

Excellent read for a beginner like me, Thank You!

 

[jimmerd82]

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Breathing

You must exercise breathing control during the aiming process. Breathing while trying to aim, with the natural up and down motion of the chest, will cause the rifle to move up and down. Up and down movement occurs while laying down. Breathing movement can be side to side when sitting at a bench rest type table when your body is against the table. You must therefore accomplish sight alignment while breathing and finish aiming in your natural respiratory pause. You do this by inhaling, exhaling, and stop at the moment of natural respiratory pause before beginning to inhale again.

A respiratory cycle lasts four to five seconds. Inhalation and exhalation take only about two seconds, thus between each respiratory cycle there is a pause of two to three seconds. This pause can be extended a couple seconds without any special effort or unpleasant sensations. Vertical strings on your target may be a indication that your holding your breathe. You should fire during this pause when your breathing muscles are relaxed. This avoids strain on the diaphragm.

You should assume your firing position and breathe naturally until your hold begins to settle.

The respiratory pause should never feel un-natural. If it is too long, the body suffers from oxygen deprivation and begins to send out signals to resume breathing. These signals produce involuntary movements of the diaphragm which interfere with the shooters concentration and lack of movement needed to make a shot. Always break your shot at your natural respiratory pause.

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Trigger Control

Trigger control is the most important fundamental of sniper marksmanship. It is defined as causing the rifle to fire when the sight picture is at its very best, without causing the rifle to move. Trigger squeeze on the other hand is defined as the independent action of the forefinger on the trigger with a uniformly increasing pressure on the trigger straight to the rear until the rifle fires. Trigger control is the last task to be accomplished before the rifle fires.



Proper trigger control occurs when the shooter places his firing finger as low on the trigger as possible and still clears the trigger guard, thereby achieving maximum mechanical advantage. He engages the trigger with that part of his firing finger (middle of the pad of the last digit) that allows him to pull the trigger straight to the rear. In order to avoid transferring movement of the finger to the entire rifle, the shooter should see daylight between the trigger finger and the stock as he squeezes the trigger straight to the rear. He fires the weapon when the reticle is in a position to insure a properly placed shot, or when the reticle is on target.

As the stability of a firing position decreases, the wobble area increases. The larger the wobble area, the harder it is to fire the shot without reacting to it, attempting to influence the sight placement when the trigger breaks. This reaction occurs when the shooter:

1. Anticipates recoil. The firing shoulder begins to move forward just before the rifle fires, thus pushing the rifle out of line with the target.

2. Jerks the Trigger. The trigger finger moves the trigger in a quick, choppy, spasmodic attempt to fire the shot before the reticle can move from the desired point of aim.

3. Flinches. The shooter's entire body (or parts thereof) overreacts to the anticipated noise or recoil (jerks). This is usually due to unfamiliarity with the weapon.

4. Avoids Recoil. The shooter tries to avoid recoil or noise by moving away from the weapon or by closing the firing eye just before the weapon fires. This again is caused by unfamiliarity with the weapon and a lack of knowledge of the weapon's actions upon firing.

Trigger control is best handled by assuming a stable position, adjusting on the target, and beginning a breathing cycle. As the shooter exhales the final breath approaching the natural respiratory pause, he secures his finger on the trigger. As the reticle settles on the target at the desired point of aim, and the natural respiratory pause is entered, the shooter applies initial pressure to the trigger. He increases the tension on the trigger during the respiratory pause as long as the reticle remains on the desired point of aim to insure a properly placed shot. If the reticle moves away from the desired point of aim, and the respiratory pause is free of strain or tension, the shooter stops increasing the tension on the trigger, waits for the reticle to return to the desired point of aim, and then continues to squeeze the trigger. This is trigger control. If movement is too large for recovery, or if the respiratory pause has become uncomfortable (extended too long), then the shooter should whenever possible, release the pressure off the trigger and start the respiratory cycle again.

The trigger finger should be indexed at 90 degrees. For right handed shooters the finger nail should point to 9 O’clock for devil lefties 3 O’clock.

Follow Through

Applying the fundamentals increases the odds of a well aimed shot being fired. There are however, additional skills, that when mastered, make the first round correct hit even more of a certainty. One of these skills is follow through.

a. This is the act of continuing to apply all the shooter marksmanship fundamentals as the weapon fires as well as after the weapon fires. Follow through consists of:

* Keeping the head in firm contact with the stock (stock weld) upon firing and after firing.

* Keeping the finger on the trigger pulling all the way to the rear when and after the weapon fires.

* Continuing to look through the scope when and after the weapon fires.

* Insuring the muscles stay relaxed when and after the weapon fires.

* Avoid reacting to the recoil or noise during and after firing.

* Releasing the trigger only after the recoil has stopped.

* Coming off the trigger or rifle will cause a drastic deviation in accuracy down range.

* Supportive hand stays in place.

b. Good follow through insures that the weapon is allowed to fire and recoil naturally, and the shooter/rifle combination reacts as a single unit to such actions.

Calling the Shot

Calling the shot is being able to tell where the bullet should impact on the target. The shooter must be able to accurately call the shots. Proper follow through will aid in calling the shot. The dominant factor in calling the shot is, where ever the reticle is when the shot is fired. This location is called the final focus point.

Body Position

The spinal cord should be straight behind the rear of the rifle. Days when you laid offset or canted behind the rifle are over. One of the big reasons behind this is to negate recoil, spot your own impacts downrange, and become more solid behind the rifle. Legs should be spread wide into a “V” with your heels flat on the ground with toes turned outward. Spreading your legs creates a larger surface contact with the ground creating a more stabile platform. Heels flat keeps adds in our stability as well, using your toes will cause you to wobble and drift your body position because you’re subconsciously trying to balance the weight of your legs with your toes.

good stuff here

 

[jimmerd82]

Battery Free Ballistics and Rangefinder

FDAC (Field Density Altitude Compensator)

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Designed for use with all MOA and MRAD adjusting optics. This product was entirely conceived, designed, and validated by Adaptive Consulting & Training Services, LLC (ACTS). ACTS is a small business completely owned and operated by former USMC Scout Snipers.

The FDAC is an analog slide rule that displays elevation and windage firing solutions using density altitude (DA). It has two sides, side (A) calculates firing solutions in MOA (minutes of angle) and side (B) calculates in 0.1 MRAD (one tenth milradian, commonly referred to as “mils”). The front of the product has a density altitude calculation table, allowing the user to easily compute density altitude with acceptable accuracy in the absence of an instrument such as a kestrel or other device that measures density altitude. The user simply inserts the slide which is the closest to the muzzle velocity of his rifle, and then slides the internal firing solution matrix (the slide) until the current density altitude and the below listed firing solutions are visible in the viewing window. All firing solutions contained in the FDAC are calculated using the G7 drag model and Bryan Litz’s tested G7 ballistic coefficients. All data contained in the three slides are the results of an extensive two year live fire testing and validation project involving several military snipers, about 20 different weapon/optic.

Adaptive Quick Card (AQC)

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The AQC is designed to be the most simple, intuitive, and accurate tool available to estimate density altitude (DA) and calculate long range firing solutions for a large array of popular firearm calibers, bullet types, and muzzle velocities.

The AQC's design is an adaptation from the FDAC (Field Density Altitude Compensator) and was completely conceived, designed, and validated by a team of Marine Scout Snipers. The AQC is intended to simplify the process of calculating a firing solution, so that all users of all experience levels can quickly and easily engage targets in austere field environments, without the use of any additional devices.

The firing solutions found within the AQC are incredibly accurate and have been extensively tested at long range to ensure data accuracy and compatibility with the wide range of firearm and optics combinations used by today's military/LE snipers and long range shooting enthusiasts.



Mildot Master

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The Mildot Master in use is fairly simple. You measure a target of known height with the Mil scale in your rifle scope. You then match the target height on the sliding scale of the Mildot Master to the milled height on the body. You then look at the arrow on the scale labeled "TARGET RANGE" and bingo! Check your ballistic table, dial in the correction and fire. No more need to remember the Mil Relation formula or worry about your calculator breaking in the field.

The Mildot Master accommodates meters instead of yards by just turning the sliding scale over. There is even a place on the back to place your ballistic table.

One last cool feature that the Mildot Master has is a scale for reading the angle to target. If you have ever shot from high angles, then you know that this will cause your bullet to impact higher than it would at the same range over a flat line of sight. There is some trigonometry involved in working out the exact "corrected" range to the target. At short distances, it really doesn’t make a difference, but at long range and high angles it does. When dealing with extreme angles, the distance to the target is typically close due to terrain. Remember to use the elevation setting for corrected distance to target (along Earth’s surface), and the windage setting setting for straight line distance to target (measured distance).

On the back of the Mildot Master, there is an angle scale. You tie a piece of string and a small fishing weight (or rock, or whatever) to the rivet labled "PIVOT". Simply sight down the side edge of the Mildot Master to your target and read the angle off of the scale. Then flip the Mildot Master over and match the angle to the scale under "TARGET RANGE". That angle will correspond to the "corrected" angle on the scale. Dial in the scope correction required for the corrected range and engage.

Alternately, you can have your spotter measure the angle of the rifle barrel while you sight in on target.

The included instruction booklet goes into great detail on how to use the Mildot Master. It even includes practice problems.

While this may not be something that everyone needs, it is definitly worth the price. If you are a Military Sniper or a LE Sniper who may have to shoot over extended ranges this is a "must have" backup to your Laser

Torque Values

Most bolts and fasteners on a rifle have a recommended torque value. Pay close attention to the units when using a torque wrench. Foot-pounds (ft-lbs) and inch-pounds (in-lbs) differ by a factor of 12. Most people will have a foot-pounds torque wrench, but few people have an inch-pounds torque wrench. Most torque specs on a rifle are in inch-pounds. Here are a few recommended torque values.

Action screws into a chassis, fiberglass stock with pillar/action bedding and/or a bedding block: 50-65 in-lbs

Action screws into an un-bedded fiberglass stock or a stock with aluminum pillars: 40-50 in-lbs

Action screws into a wooden stock: 35-40 in-lbs

Scope base screws: 15-30 in-lbs

Scope ring cross bolt/nut: 50-65 in-lbs

Scope ring cap screws: 15-25 in-lbs

Barrel into action: typically 100 ft-lbs, but custom rifles will vary.

Note: These are typical values commonly found on most of these products. When you purchase a new piece of equipment, the manufacturer will include a torque value or they will list the information on their website.

When installing any of these components, you must take into account recoil. Most scope rails are equipped with some sort of recoil lug that hangs down into the ejection port of the action. When installing a scope rail, make sure the rail is pushed firmly forward. Scope ring lower halves must also be pushed forward against the lugs of a picatinny rail. It also helps to hold the ring half firm against one side as you tighten the bolt/nut. Scope ring caps should be installed using a ‘star’ pattern such as tightening lug nuts on a vehicle’s wheel. One difference is, when installing the barreled action into the stock, make sure the recoil lug is firmly against bedding or stock material before you torque those screws. It helps to get the screws started and stand the rifle up onto its recoil pad for final torque.

Scope Mounting

Some people think there is some voodoo involved with leveling a scope in the rings. From plumb bobs to a set of 3 levels, we’ve seen them all. The easiest and most accurate way is to use a set of feeler gauges. You can place these feeler gauges in between the scope’s erector housing and scope rail. Add or remove the amount of feeler gauges to take up the space between the two. Tighten the scope caps with the feeler gauges under the scope. This guarantees the scope is level in the rings and is level to the base which should be level to the action.

Cleaning and Maintenance

Fouled, warm bores are predictable. Fouled, cold bores as slightly less predictable. Clean, cold bores are even tougher to predict. Very seldom will you ever witness a long range shooter take an important shot on a target with a clean, cold bore. They want to have a layer of fouling in their bore to insure the shot they are about to take is as consistent as the shots they have taken previously.

You want to manage the fouling in your bores by routine cleaning. You do not want to clean a barrel squeaky clean. When you clean down to bare metal, you are removing all traces of copper and carbon that ‘smooth’ the bullet as it travels down the bore. This is especially true with factory barrels, and not so much as with hand lapped custom barrels. When you remove this fouling completely, you will have to deposit it back by shooting to regain the consistency. By removing most of the fouling, you will regain consistency is few to zero shots.

We seldom clean our bores. By seldom we mean, every couple hundred rounds or when accuracy falls off. The reason is because you can damage a barrel more by cleaning it than shooting it. Why would we unnecessarily clean of bore if it doesn’t need it? It only creates a risk of damaging your bore. With that said, we typically follow a set procedure to manage the fouling in our bores. Every 250 rounds, we will clean the carbon out of the bore while leaving the copper. This ensures we will retain our zero sooner while keeping the bore somewhat clean. Your rifle will be different. Pay attention to accuracy. If accuracy drops off for no apparent reason with a couple hundred rounds down the tube, a cleaning may be the trick.

Bore Guides

A bore guide is absolutely critical when cleaning a precision rifle. It ensures that the cleaning rod is held in the center of the bore while providing some additional stiffness to the rod by adding another point of support. It protects the chamber by usually sealing it off with O-rings. It protects the action and stock finish by shielding them from cleaning solutions. They are relatively in-expensive considering the insurance they provide. One of the best bore guides is the Lucas Bore Guide. It is a custom made bore guide to your cartridge, action and cleaning rod. It offers very good protection of the action, and precise alignment with its two-piece design. They can be purchased for about $60.

Cleaning Rods

A cleaning rod is also critical for cleaning. Gone are the days of the jointed cleaning rod. The segments can easily be off center allowing an offset of the rod pieces. This creates an ideal method to shave and scrape your barrel. Stick with solid one-piece rods. Dewey and Tipton stainless steel and carbon fiber rods are highly recommended. They offer the right amount of stiffness with ball bearings in the handle to glide along with the rifling. They come in various lengths and diameters. Just be certain to select one long enough when using a long barrel and a bore guide.

Cleaning Solutions

There are tons of bore cleaning products on the market. Most will do a good job. Some will do a great job. We like to use KG Products. They are ammonia-free and can be used to target carbon and copper separately. Please use caution when using any product with ammonia. Do not let ammonia based products stay in a bore for very long at all. It will etch the barrels and result in a great increase in fouling.

Patches and Jags

Have you ever seen someone clean their teeth with a stainless, copper or bronze brush? Then, why would you use it on your barrel. Stainless, copper and bronze brushes shouldn’t be used on precision rifles. Instead, use a nylon brush if you must. Stick to jags and patches with cleaners. Let the chemicals do the work. Never run a nylon brush or jag with a patch back and forth in the bore. Always push the rod to the muzzle in the travel of the bullet. Pay close attention to the crown. I never pull a jag or brush back through the bore. I will remove the jag and slide the rod back.

Chambers and Actions

We like to keep our chambers and actions relatively clean. Few good things can come from a filthy chamber and action…jams, pressure spikes, you name it. After a few shooting sessions, we will run a clean, dry cotton mop into the chamber and spin it by hand. This will remove any loose carbon or debris in the chamber. A quick wipe down of the bolt and action with a clean, dry rag is in order also. From time to time, we will swab out the lug recess in the action, but this requires a small tool to hold the swabs. Be sure to apply a thin layer of grease back onto the bolt lugs. You want just a dab, not enough to think it even does anything. This helps with galling of the lugs. Pull the bolt apart every so often to make sure all inner workings are clean of debris and are lubed. Use caution here, grease on the firing pin can draw condensation over time. Take the rifle hunting in the cold, and you may have a firing pin frozen in place. We like to use a light dusting of dry lube on the firing pin itself.

Data Books

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A data book is a book that holds a wealth of information about you and your rifle. From serial numbers to scope settings for a specific stage in a competition, a data book can keep it all organized. They are most helpful in storing ballistics for your rifle or DOPE, Data On Previous Engagement. You can log each of your shots in different conditions and refer back to them when in similar conditions. Multiple companies make them with multiple layouts. We recommend Impact Data Books. It is owned and operated by a former Scout Sniper and current competition shooter. He allows you to organize your data book to your specific needs. From target shapes to range cards, he makes all the sheets to track your shots in training and competition. He also uses a set of reference pages of useful info. One important piece of advice: garbage in = garbage out. Your data book is only as useful as the information you enter into it.





ACKNOWLEDGEMENTS:

8541 Tactical (www.8541tactical.com)

Shooting Voodoo (www.shootingvoodoo.com)

Sniper’s Hide (www.snipershide.com) Online training/ DVDs

Impact Data Books (www.impactdatabooks.com)

Mil-Dot (www.mil-dot.com)

SWFA (www.swfa.com)

JBM Ballistics (www.jbmballistics.com)

good information. THank you for posting it.

 

[bonesaw00001]

Very much appreciated!

 

[drod53]

Tag! Thank you for the info!

 

[Skydiver22]

Just found this.... great info, thanks for taking the time to put it all in one place.

 

[Thurm]

Great refresher on some topics. I’m all over the place with my hobbies, hunt, fish, shoot, hoops, marshal arts. Since I’m not immersed 24/7, refreshers are nice. Thanks

 

[CanonSterVA]

Read this once before but had to come back to refresh.
Great information.
Myron

 

[Top6517]

Just read this. Wow, didn't know how much I didn't know awesome consolidation!

 

[FTG-05]

Good stuff!

Who here has used to Mildot Master? Something useful and/or needed for someone shooting mostly at 100-200 yards?

 

[JBBushnell]

Good stuff!

Who here has used to Mildot Master? Something useful and/or needed for someone shooting mostly at 100-200 yards?

Newer member and was browsing through thread and saw your post. I have a Mildot Master and have I've played around with it some, but not used it in the field. I don't believe it would be useful at those distances. I suggest setting your scope to zero at 150-200 yards and shooting dead-on (assuming that your big game hunting).

 

[ECHO-5-PAPA]

Solid read, sometimes rereading the basics is a bit eye opening on knowledge we take for granted.

 

[eelman308]

Great read and good info. Thank you.

Is there a way to "bookmark" this?

Thanks

 

[tlr16]

Something to go back and read. Go back to the basics and start over at times. I know I learn bad habits myself then need to look back and reset.

 

[socchia16]

Wind Reading

The single most unpredictable element in long range shooting is the wind. There is always air movement even though you may not feel or see it. Wind can be determined from two departments, art and science. Art refers to monitoring everything between you and the target. The tree leaves moving, tall grass swaying and any other clues you see. Science refers to taking reading with a meter to be addressed below. Together, these two methods will give you the best tools to make a call on the wind. Mirage discussed blow is another tool to use; however, it is much harder to see compared to objects moving in front of you.

Wind is not constant. It is not side to side or front to back. It moves about the terrain around you. It is best to visualize how water would flow over a given terrain. Water and air are both mediums. The air will flow over hills and valleys just as a river flows over rocks, through bends as well as eddies. Chances are the wind will change as soon as you’ve made a wind call. You will need to be on the fly with your observations. Feel the wind. If you get a funny feeling that the wind is going to change, don’t shoot. Wait for your next respiratory pause to shoot.

There have been some discussions as to what area the wind matters most. The wind closest to the shooter since the wind has longer to act upon the bullet. The wind at the target since the wind has a greater effect on the bullet due to a diminished velocity. It all matters. Focus on the entire distance to the target.

Not all wind is acting equally upon your bullet once fired. Depending on the direction the wind it coming from, it can be classified as full-value or half-value. After you have determined a wind speed, check your ballistics for the corresponding wind drift. If the wind is nearly side to side, apply that full-value to your firing solution. If the wind is coming at an angle, apply the half-value to your firing solution.



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Mirage

Mirage is the distortion of light by alternating layers of hot and cold air. A prime example of this is looking over asphalt pavement on a hot, summer day. The image you see appears to be boiling. As you can imagine, this is nearly impossible to accurately shoot through. Mirage is best dealt with by reducing you scope’s magnification; however, it only reduce its affects on summer days. Even on cooler days, mirage is still present as heat is radiating off of the ground. Mirage can be useful in determining wind downrange. By estimating the angle the mirage makes, you can estimate wind speed. When the mirage is coming towards you or away from you, it is known as a boil. You are best not to shoot through a boil as the mirage is actually distorting the image higher or lower than it actually is. As a result, your point of aim may be higher or lower than it should be.



Environmental Conditions

Temperature. Temperature is one of the main influences on long range shooting. It influences the trajectory of the bullet, the temperature of the barrel and in some cases the ammunition we are using. Temperature is fairly easy to measure and predict. It has a moderate effect on trajectory.

Elevation. Elevation is another variable in conditions. It is the easiest to measure and predict. Elevations do not change without you moving, and we can fairly well determine what the temperature will be briefly into the future. It has a moderate effect on trajectory.

Pressure. Pressure is the air pressure around you. It can fluctuate easily without you knowing it. Since pressure affects the air density the bullet must travel through, it has a major effect on trajectory.

Humidity. Humidity is amount of water vapor in the air. Higher humidity does not equate to more dense air. It is actually the opposite. Higher humidity is actually less dense air due to the water vapor expanding. It has the least effect on trajectory of the environmental conditions.

Density Altitude. Density altitude (DA) is an altitude equivalent on a specific set on conditions involving temperature, elevation and pressure. It comes from the aviation industry where aircrafts will encounter different conditions in various airports and flying altitudes. It is used to determine the air density. As the DA rises, the air is less dense. Inversely, as the DA drops, the air is more dense. For shooters, this comes into play as ranges increase. In a higher DA, our bullet has a flatter trajectory because the less dense air allows our bullet to slide through the air more easily. It is possible to have a negative DA, especially in the winter time.

From a shooter’s standpoint, DA is much easier to equate a set of environmental conditions to a single number. 3,300 feet DA is much easier to use than 1,500 feet elevation, 78*F, 29.95 in Hg and 64% humidity. By taking notes on shooting from a day that the DA was 3,300 feet, you can also use the same set of firing solutions months from now when the DA is 3,300 feet. Many ballistic calculators and software now accept DA to input for your conditions. It is just much easier and quicker to use a single number.

Kestrel Meters.

Kestrel meters are popular in the long range shooting world. They give instantaneous and a history of environmental conditions as well as determining wind speed and direction. They range in price from $75 to $600. The 4000 ($250) and 4500 ($310) models will provide you with a DA reading. It is important to understand that these meters give you the conditions at the shooter. Conditions at the target are typically the same except the wind. You will need to use your wind reading skills to determine the wind downrange and at the target. These meters are an excellent tool to use to estimate and check the wind speed. With some practice, you will be able to determine the wind speed by the objects around you as mentioned before.

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Ballistic Coefficients

Whatever type of ballistics you use, you will need to know the ballistic coefficient of your bullet. A ballistic coefficient (BC) is a measure of the bullet’s ability to overcome air resistance in flight. It is a function of mass, diameter and drag coefficient. The higher the BC the more slippery the bullet is as it flies through the air. Most bullets for long range have a good BC. A higher BC will allow a bullet to retain its velocity aiding in trajectory, wind drift and retained energy. Ballistic coefficients are not set in stone. They will vary upon velocity. Typically, the faster the bullet starts out, the higher the initial BC is. As it begins to slow, the BC will be reduced some. This is very important when entering your bullet’s BC into ballistic software. When entering into software, you may come upon multiple drag models for a particular bullet. The most common are G1 and G7.

G1. The G1 drag model coefficient is the number usually given or displayed by bullet manufacturers. The G1 coefficient describes a blunt nose, flat base bullet. Most long range bullets are typically not of this form, but it can be used for trajectory calculations.

G7. The G7 drag model coefficient describes a long, sleek bullet with a boat-tail. It more accurately depicts a long range bullet. Ballistic software using a G7 coefficient usually yields a trajectory close to the actual trajectory.

Different Types of Ballistic Software

There are quite a few ballistic programs available online or on a mobile device. Some are rough and quick while others are detailed and complex. You just need to dig into a program and see how it performs for you. I prefer to use JBM Ballistics. It allows you to control all inputs and outputs. You can create your own range cards for different conditions even look up bullet lengths and stability calculations. It’s all there.

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Some commonly used ballistic software are: Field Density Altitude Calculator, Adaptive Quick Card, JBM Ballistics, Field Firing Solutions, Ballistic AE and Shooter. The quality of the information you enter will determine the quality of the outputs. Typical parameters are: bullet, BC along with drag model, muzzle velocity, distance to chronograph, scope centerline above bore centerline measurement (sight height), temperature, pressure, altitude and humidity. Always pay attention to units, and it never hurts to make sure the output makes sense.

Once could write a book on ballistics and software. In fact, Bryan Litz has quite literally wrote the book. When selecting any bullet BC or drag

model, you can refer to his findings to rely on solid information.



Chronographs

Chronographs are used to determine a projectile’s velocity. They normally use two sensors with a timer. The unit will compute the time it takes to travel between the sensors and provide you with a reading. They are fairly accurate, but some inconsistencies can arise. Lighting conditions, bullet turbulence and distance to chronograph all come into play. Generally, a chronograph’s reading is taken as gospel. They should not be. They are close but may not be the actual velocity. Different manufacturers allow different tolerances for their components within a chronograph. It is best to use the average reading from a chronograph to begin to develop ballistics for your rifle. From there, you can ‘true’ your ballistics by varying the velocity from known scope settings and environmental conditions. One key piece of advice, place the chronograph ten feet from the muzzle and in the shade (if possible) for the best readings.

Angled Fire

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in regard to the angle of fire (step one) i believe a map range will not require a cosine to be applied, as it is already on a vertical 2D plane.

 

[larry meyer]

Just found this. Thank you, Valuable info, very methodically presented. Just getting in to LR, answers a number of my questions

 

[Cobiwan]

I appreciate you posting this Boone. It's a very informative introduction to getting started in PRS.

 

[NoScope]

First off, awesome post. Really helped a lot when I was transitioning to long range. Are there any recommendations you guys would make for resources where I can learn info beyond even this?

 

[ReplicaSnipers]

First off, awesome post. Really helped a lot when I was transitioning to long range. Are there any recommendations you guys would make for resources where I can learn info beyond even this?

Have you checked out the Precision Rifle Blog online. It’s written by Cal Zant and he has some fantastic articles on research into ballistics and does gear comparisons, statistics for shooters, etc. Also if you haven’t already get the Brian Litz books especially the ‘Modern Advancements…’ series now up to book 3. Jam packed with awesome info’ and myth dispelling research. Both Zant and Litz are really easy to read and they make what could be dry topics enjoyable.

 

[Makata]

Thank you for this!

 

[Milf Dots]

I'm not new to pistols & carbines, nor new to formal training, but this "newb to precision rifle" found this thread helpful.

 

[RooftopKorean]

This is going to seem like a really silly question. With my intro into PRS the one thing I have struggled with is keeping my rifle on target after the shot to see point of impact on paper targets.

Maybe it's me and poor recoil management, but is there anything I can improve to help this? Obviously when shooting steel you can hear the impact and with if it's freshly painted you can see the impact point.

From my first class I took last year, the instructors said my prone position and rifle placement in the shoulder was fine. It's definitely more noticable when I'm bench shooting.

As you mentioned follow through is critical, so I must be doing something wrong in that step but I can't seem to figure out the issue.

Great post by the way, it was extremely informative.

 

[ReplicaSnipers]

Are you using a suppressor or a brake? What caliber are you shooting? What scope magnification setting do you usually use? Need a lot more information.

 

[RooftopKorean]

Are you using a suppressor or a brake? What caliber are you shooting? What scope magnification setting do you usually use? Need a lot more information.

RPR in 338LM using an Arken EP5 at full magnification at 1000 yds, hold overs and elevation shots at 9.3 mils at steel targets.

Brake at the time was the factory Ruger brake. I haven't shot it since I've upgraded the brake to an Area419 Hellfire.

Paper targets at 500 yds using my heavily modified Ruger American in 6.5CM using an Arken EP5 with an Area419 Hellfire brake. I dont recall the magnification I was on, elevation 2.9 mils

I was using Hornady ELD Match for both calibers.

6.5 was 143 grain
338 was 285 grain

Only thing I thought about doing was placing my offhand on top of the scope by the turrets for more stability when bench shooting. I'm not sure if it would be conducive for prone shooting.

 

[ReplicaSnipers]

Sometimes a better break will help. Recoil needs to be directly backwards. Any tension in the system eg. Grip, pulling in tight, etc. will mean the recoil goes on an angle and will lead to muzzle jump. Using the highest magnification will decrease your field of view and exaggerate mvmt on the target. Backing off can make the sight picture much more stable. Remember aim small hit small. There’s a YouTube channel called Mark and Sam 4AW, if you check out Mark’s alignment you’ll see how the muzzle doesn’t seem to move much, just backwards, even with .50 BMG, etc.

 

[Punkur67]

RPR in 338LM using an Arken EP5 at full magnification at 1000 yds, hold overs and elevation shots at 9.3 mils at steel targets.

Brake at the time was the factory Ruger brake. I haven't shot it since I've upgraded the brake to an Area419 Hellfire.

Paper targets at 500 yds using my heavily modified Ruger American in 6.5CM using an Arken EP5 with an Area419 Hellfire brake. I dont recall the magnification I was on, elevation 2.9 mils

I was using Hornady ELD Match for both calibers.

6.5 was 143 grain
338 was 285 grain

Only thing I thought about doing was placing my offhand on top of the scope by the turrets for more stability when bench shooting. I'm not sure if it would be conducive for prone shooting.

Fundamentals are the most important. Weight helps a ton too. Most comp guns weigh 20#+ . Many people shoot lighter guns with success but weight reduces recoil a ton.

 

[RooftopKorean]

Fundamentals are the most important. Weight helps a ton too. Most comp guns weigh 20#+ . Many people shoot lighter guns with success but weight reduces recoil a ton.

I agree with the weight. I do notice the recoil is less with my modified Ruger American. The barrel that Precision Firearms made me is 26" and very heavy, I didn't get it fluted yet.

The weight is rather nice though, the rifle is perfectly balanced.

 

[PeskyPeel]

You typed up your section on MOA vs MIL as if you cant see how many MOA off your impact is from your point of aim. You yourself said they are both angular measurements, so assuming you are using a FFP scope or you have a SFP scope and your magnification as true with your reticle ticks, you can use both MOA and MIL the exact same way to visually see how much you need to adjust.

For example, you say "You see the impact is 6" low", when in reality, you would compare the point of impact against the point of aim in your scope, see "Ah, I am 1.5MOA off", and adjust your scope 1.5MOA with no math needed. I have been shooting MOA scopes for years, and have never done the math to make adjustments - it is all visual.

 

[ReplicaSnipers]

You typed up your section on MOA vs MIL as if you cant see how many MOA off your impact is from your point of aim. You yourself said they are both angular measurements, so assuming you are using a FFP scope or you have a SFP scope and your magnification as true with your reticle ticks, you can use both MOA and MIL the exact same way to visually see how much you need to adjust.

For example, you say "You see the impact is 6" low", when in reality, you would compare the point of impact against the point of aim in your scope, see "Ah, I am 1.5MOA off", and adjust your scope 1.5MOA with no math needed. I have been shooting MOA scopes for years, and have never done the math to make adjustments - it is all visual.

How much time does it take to make sure you are on the right magnification for your reticle to be true, then reacquiring your sight picture to make the measurement to then adjust your scope?

 

[PeskyPeel]

How much time does it take to make sure you are on the right magnification for your reticle to be true, then reacquiring your sight picture to make the measurement to then adjust your scope?

Same amount of time no matter if your scope is MOA vs MIL, so the argument still stands.

FFP: measure error using reticle and adjust accordingly for either MOA or MIL.
SFP: both MOA and MIL scopes need to be at correct magnification for reticle to be true.
His section on MOA vs MIL is an argument for FFP vs SFP that is incorrectly portrayed as MOA vs MIL.