Medford Rifle and Pistol Club

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Fullbore Rifle Practice

Medford Rifle and Pistol Club

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FULLBORE RIFLE PRACTICE

We will shoot Wednesday July 5th at the Camp White Range at 5 PM at 600yds.

22 rounds prone or bench.  It is going to be hot but we will give it a try. Frank 541 899 6872

New Member Orientation

Wednesday July 5^th–TONIGHT at 7pm

STEEL CHALLENGE

SUNDAY July 9^th Starts at 9am

Come early to sign-up and help set-up

Reserve & Competition Ranges at

The Jackson County Sports Park

12 Issues With Extreme Long-Range Shooting

by G&A Staff   |  June 14th, 2017   |  Know the factors and their effect on shooting. 0

By Todd Hodnett – Photos by Mark Fingar

The definition of long-range shooting has been redefined over the last few years. We are now pushing further than ever, and not just launching bullets in hopes of seeing splash and making second shot corrections until we hit a target. We’re doing the math and accurately calculating for elevation at extreme ranges. Wind will be wind, so it will always be hard to ensure a perfect wind call at extreme long ranges, but that is what makes long-range shooting challenging.

Rangefinders are better and more affordable. Scopes can dial more accurately and with more vertical adjustment. Ballistic engines, like the Kestrel AB, give us incredible data. So when we talk long-range shooting, we are really talking about problem solving.

These are a few things we need to seriously consider. For these comparisons, we used a .300 Win. Mag. with 190-grain Sierra MatchKing (SMK) ammunition at sea level DA (density altitude).

ISSUE #1

RANGE ERROR
Range errors can occur with most laser rangefinders, and they become a huge problem at extended range. Even with an error of only 20 meters, the difference in drop becomes significant.

THE SOLUTION
One of the best ways to avoid this error is to hit and then miss the target with the laser. If the numbers are the same, there is a good chance you are not hitting the target.

ISSUE #2

PARALLAX
Parallax is a huge problem with most of the shooters I train due to their young eyes. By not getting all of the parallax adjusted out of a scope, something as small as .2 mils of parallax could result in a shot being 15.72 inches off.

THE SOLUTION
In addition to focusing the image and reticle onto the same plane by means of a parallax adjustment, another way to remove parallax is to center your eye in the scope. Do this by making sure you have a little scope shadow showing equally all the way around the ocular lens. I even teach students to set up their cheekweld this way. Thus, if you have any
parallax in the scope when you take the shot, you can be assured the reticle is on the target where you perceive it to be.

ISSUE #3

MV / ES
Muzzle velocities (MV) and extreme spread (ES) are huge components of hit probability at long range. When shooting a .308 at a mile, I will ignore shots that strike outside the norm of the group the gun is shooting. Here’s why:
Whether you are reloading or have great store-bought ammo, you might expect standard deviation (SD) to be around 7 and ES to be around 20 feet per second (fps). But a lot of ammo may have 40 to 70 fps ES, which, as you can see in the chart, is a point of concern.

THE SOLUTION
Demand quality ammo when shooting long range. Whether it’s factory ammo or precision reloads, make sure the ammo produces consistent muzzle velocities in your rifle. If it doesn’t, use it for short-range applications instead of long range.

ISSUE #4

MV AND TEMPS
Muzzle velocity temperature sensitivity is when the velocity can swing wildly with variations in temperature. We have seen as much as 160 fps in a 100-degree swing. We have even seen more than 50 fps with a relatively minor swing of 20 degrees. This is not a linear adjustment, so shooters must know the temperature sensitivity of the powder being used.

THE SOLUTION
Getting data at sea level and 80 degrees can have a huge adjustment in elevation calculations when going to 8,000 feet DA in 30-degree weather. The ballistic engine will calculate for the DA portion. But one must have MV temperature tables running for the engine to calculate for the powder temperature sensitivity.
This is similar to ES when calculating hit probability, but it’s actually greater because all of the bullets will be off by this much instead of one out of five being a flyer.

ISSUE #5

TEMP / HUMIDITY / DA
In sniper manuals, it states that 20 degrees will give a point of impact (POI) shift of 1 minute of angle (MOA). This is true at 1,000 yards but nowhere else. When looking at DA, understand that temperature will give the largest difference in holds at distance. It takes 14 degrees to change your DA by 1,000 feet.
So let’s look at the difference in elevation holds at different distances with 1,000 feet of DA, which is equivalent to a 14-degree temperature change at altitude.

THE SOLUTION
Elevation is consistent, but temperature requires staying on top of changes throughout the day. Inside 500 meters it may not be a big deal, but it begins to be a problem at 1,000 meters and beyond.

ISSUE #6

WIND DIRECTION
Headwinds and tailwinds are of no real consequence at shorter ranges. However, as distances stretch, this variable can affect the time of flight (TOF) to the target, and TOF is everything. We took a 20 mph headwind and tailwind and compared the different actual holds using the Applied Ballistics (AB) engine, which calculates for this variable.

THE SOLUTION
Factor in the direction of wind whenever you shoot long range. Not doing so will result in substantial misses.

ISSUE #7

CLICK ERROR
Because many scopes don’t dial what you put in and some don’t repeat back to zero — dialing 20 mils may only give you 19.6 — you need to perform a calibrated test to measure the impact of each round. At 100 yards, a yardstick is 10 mils. So, if you are square to the target you
should show a 10-mil coverage on the target, and your bullet should move up that much when dialed 10 mils. Any error should be linear.
It could look something like this: At 500 meters, it may be off .1 mil, while at 1,000 meters it may equal .2 mils. Then .3 at 1,500 meters and .4 at 2,000 meters. These click errors quickly accumulate into inches.

THE SOLUTION:
Test your optic and make sure it tracks true. If not, those carefully launched bullets won’t land where they should.

ISSUE #8

SPINDRIFT AND DOF
Spindrift is one of the easiest variables to account for, as the ballistic engines do a good job of giving accurate data for it. But let’s look at the same ranges and how much that is in mils and inches.
Direction of fire (DOF), however, is really talking about Coriolis effect. So let’s look at a shot without the correct DOF input. Let’s say we indicate we are shooting north but we are shooting east, which gives us about half the Coriolis effect.

THE SOLUTION
Make darn sure your ballistic engine knows all of the variables. Spindrift, while quite easy to account for, must be factored into the equation. Also, recognize the direction you are shooting. DOF makes a big difference.

ISSUE #9

DRAG MODELS
All ballistic engines are not created equal. While standard drag models such as G1 or G7 work fine out to transonic range, they don’t predict what happens in the subsonic realm very well.

THE SOLUTION
Use custom curves that Bryan Litz and Applied Ballistics have tested extensively to determine what your bullet is really doing at range. These engines work extremely well.

ISSUE #10

AERODYNAMIC JUMP
Aerodynamic jump (AJ), or the deflection of a bullet due to wind direction, can play a huge role when shooting out to distance. If one has not accounted for AJ while truing, this could easily incur an error of 30 fps in the MV. Even if the AJ was accounted for while truing, the effect on the bullet can destroy any chances of making shots at long range.
Let’s look at 12 mph, which is small but will account for a .15 mil deviation on target, and see what this means for long range.

THE SOLUTION
Understand what AJ is and how to account for it while shooting long range.

ISSUE #11

BAD BC
Unfortunately, bullet companies don’t always give you the proper BC one should use in a ballistic computer. Instead, they give the BC at the muzzle. This same error will not affect your ability if you true on any targets you engage out to transonic. However, it is not uncommon to see as much as 2 percent deviation from actual BC to what a company may represent as the stated BC.

THE SOLUTION
Instead of trusting listed BCs, run a drag scale factor (DSF) to morph the predictive and actual algorithms back in line in the subsonic regions. This will provide a much more accurate prediction of what the bullet will do at long range.

ISSUE #12

WIND VELOCITY / COSINE
Always the nemesis of the long gun, cosine (the way we assign value to wind speed if it’s not blowing perpendicular to the bullet’s path) is a huge problem that gets increasingly difficult with range. Not only is reading wind exponentially harder with range, now we have to get the cosine-determined wind value perfect as well. What I want to show you is math that only relates to a miss estimate of 1 mph. An error of 1 mph wind speed yields this much distance between our expected point of impact and our actual point of impact.

CONCLUSION:
At the end of the day, I am not trying to discourage anyone from extreme longrange shooting. However, I do want to show the challenges in making shots at truly long ranges. And again, I am not talking about shooting and doing corrections until you finally get a hit 50 rounds later. That is not true long range. That is having fun, and there’s nothing wrong with that.
There is a different set of skills that allows a shooter to be “on” at extreme ranges in only a shot or two. This is the sought-after skill in long-range shooting. Even though control or even being aware of all the variables may seem overwhelming, this is the challenge, and accurately calculating for each can be a rewarding feeling.

Read more: http://www.gunsandammo.com/tips-tactics/12-issues-with-extreme-long-range-shooting/#ixzz4kSVOmBSt

Medford Rifle and Pistol Club

ON-LINE NEWSLETTER

June General Club Meeting

This Wednesday, 6-21-17 @ 7pm

At the Club’s Indoor Range Meeting Room

FULLBORE  RIFLE  PRACTICE

Wednesday, 6-21-2017 @ 5pm

at

Camp White Historic Rifle Range

Off Kershaw Road @ Ja. Co. Sports Park

22 Rounds will be shot Slow Fire from 600 yards

Any Centerfire Rifle, Calibers up to 35 caliber

Prone and Bench Rest Shooting

IDPA MATCH

This Weekend  June 24^th—8am

Reserve and Competition Ranges of

the Jackson County Sports Park

IDPA offers an exciting forum for practical shooters in which truly practical equipment,

techniques and courses of fire are mandated.

Prior to IDPA, there was no place to compete with common service pistols.

There were no shooting sports where your concealed carry holster could also be your match holster without handicap.

When you come to an IDPA match, you can not only use your duty/CCW equipment, you can be completely competitive with it!

Other shooting sports have become equipment “races”; IDPA will not.

If you’re interested in using truly practical pistols to solve challenging and exciting defensive shooting problems,

then IDPA is the sport for you.

Learn more about what makes IDPA great, from the practical skills training rules,

the variety of matches, the wide range of competitors and the ever growing community.

More Information Available At :  http://www.idpa.com/

This Month’s Steel Challenge Results

Fastest Shooter with Lowest Combined Time Wins

Each Stage is shot 5 times, and the slowest time for each Stage is thrown out.

A total of 5 Stages are shot, and the aggregate time is the Score.

Shooter only compete against other people shooting the same type of firearm. 

PCCO=Pistol Cartridge Carbine Open,   RFRI=Rimfire Rifle, RFPO=Rimfire Pistol Open,   RFRP=Rimfire Rifle Open

RFPI=Rimfire Pistol Iron Sights?,   LTD=CenterFire Pistol Limited/Stock?,   REVI=Centerfire Revolver Iron Sights,

REVO=Centerfire Revolver Open,  (Open =Modified Firearm, Limited=Stock or UnModified Firearm)

G&A Basics: The Science of Hearing Protection

by B. Gil Horman   |  August 22nd, 2013

It is estimated about one in 10 Americans has hearing loss that affects the ability to understand normal speech. The most common cause of this condition is excessive noise exposure. It just so happens shooting firearms is a popular activity that subjects its participants to noise levels intense enough to cause permanent hearing loss, unless the proper precautions are employed.

But how loud can a gun really be? It varies some depending on the firearm and ammunition used, but the sound is more intense than one might think. If we were to measure the report of a rifle, the sound would be checked for the following:

Frequency: from low to high sounds, measured in hertz.

Duration: how long the report lasts.

Intensity: how soft or loud a sound is, measured in decibels (dB).

It’s important to note when sound levels are represented in decibels, the increase in sound intensity is expressed in a logarithmic scale. The softest audible sound—near total silence—is represented as 0 dB. A sound 10 times more powerful is 10 dB. A sound 100 times more powerful than near total silence is 20 dB. A sound 1,000 times more powerful than near total silence is 30 dB. This means a change in volume from 150 dB to 140 dB is a more significant reduction in noise intensity than reducing 50 dB to 40 dB.

To clarify how loud a sound measured in decibels can be, it’s helpful to have some everyday sound comparisons to work with. Normal conversation occurs at 60 dB. Lawn mowers run at 90 dB, a jet engine at 140 dB, and the noise on a rocket pad during launch pushes the top end of the scale at 180 dB. So where does gunfire land in the lineup? When a gun goes off, the report slams into bare eardrums at 140 dB or more.

Some are incredulous at this revelation, saying there is no way a gun is as loud as a jet engine. However, they are confusing sound duration with sound intensity. The sound of a gunshot only lasts for a fraction of a second, but in that short time, it’s very loud.

How Much Can the Ear Take?
So what level of sound intensity is too loud for the human ear? Most experts agree you would have to be exposed to eight continuous hours of noise at 85 dB to cause permanent hearing loss, but sound spikes of 130 dB or more can cause permanent damage instantly.  This means every shot fired has the potential of damaging the ears of anyone within close hearing range. Again, there will be more incredulity at this information, since readers will say they’ve heard loud noises in the past and can still hear just fine. Here are two important things to remember:

The various tissues of the human body do not respond to duress in the same way

Permanent hearing damage can go unrecognized because it is cumulative in nature.

The human body contains an amazing variety of systems, each with specialized tissues to fulfill different tasks. Muscle tissue, for example, can become stronger after being strained. The first time you try a new physical activity—rock climbing, surfing or ballroom dancing, for example—muscles that have not been used quite that way before will become sore and tired. If the activity is continued over time, the muscles will adapt and become stronger. Eventually you will be able to continue those activities without becoming sore like you were the first time. In other words, our muscles adapt and become stronger.

However, the specialized tissues of the nervous system—including brain functions and hearing—do not respond to abuse by rebuilding themselves to become stronger. Instead, when they take enough abuse, they lose their functionality for the rest of a person’s life.

For example, think of all the professional boxers over the years who were amazing athletes in their prime, but were left with crippling brain damage by the end of their careers. They successfully toughened their muscles to Olympic-competition levels, but their brains slamming against the interior of their skulls with each blow taken to the head caused irreparable harm. It doesn’t usually happen in a single fight—although it can—but brain damage adds up over time. It’s exactly the same process with hearing loss. Each loud sound—whether in short or sustained bursts—is like a punch to the ear. It may not seem like a big deal at the moment, but it adds up over time.

Because hearing loss is painless and gradual, it can go unnoticed until the loss—or related symptoms—are quite severe. Many people think losing hearing is like turning down the volume on a television set; all the sounds get softer and softer until you hear nothing at all. That’s not the case, especially with noise exposure. What loud noises can do is punch holes in your hearing at certain spots along the frequency line. I know one sportsman who was shooting a particular gun almost every weekend for several seasons without hearing protection. When he did get his hearing checked, sure enough, along with some general hearing loss he had a gap (i.e., deafness) right at the sound frequency produced by his gun and ammunition combination. Ears do not get tougher with exposure to noise; they just stop working.

Besides hearing loss, there’s the symptom of tinnitus. From the Latin word for “ringing,” tinnitus is the perception of a sound when no external sound source is present. Don’t panic if you’ve had a little ringing in your ears at some point, that’s normal. However, if you are around noise loud enough to cause your ears to ring, it’s a good indicator that your hearing is in danger of damage. If enough damage is done, the ringing may not go away.

How to Protect Your Hearing
So how exactly should shooters go about keeping their ears safe? The obvious answer is to use hearing protection devices like sound muffling earplugs and earmuffs. These items should have a sound-reduction rating on the package shown in decibels (e.g., 21 dB, 30dB). The higher the number, the more noise they block.   But if guns make 140 dB of noise, how is a 30 dB plug going to help? First, the noise tends to travel forward of the muzzle, so the shooter’s ears are not always hit by as much noise as the gun produces. This does not mean the level of sound is safe—only reduced. Second, the purpose of hearing protection devices is not to eliminate sound, but to reduce the impact to a level that does not cause lasting damage. In short, a plethora of scientific studies  conducted over many years show hearing protection works, and it works at the sound-muffling levels common devices provide.

With hearing protection so high on the must-have list these days, most shooting ranges will have some form of hearing protection on hand for their customers. Hardware stores and gun stores also have a variety of options in stock. The cheapest form of hearing protection at pennies apiece are the disposable foam earplugs, which usually provide somewhere between 25-31 dB of hearing protection. Reusable rubber-type plugs are also available, ranging from $5-15, depending on the make and model.

The next step up from ear plugs are the ear-protecting muffs, which have the advantage of being reusable for years. The basic clamp-over-the-ear units can run from $10-40, providing the same 25-31 dB levels of hearing protection as the foam plugs. A popular option in really noisy areas like the indoor ranges is to use both plugs and muffs. This is a good idea, but understand the limitations of this system. A 30 dB plug and a 30 dB muff together do not provide a cumulative 60 dB of hearing protection. Instead, they each act as a separate barrier the sound must travel through successively. Hearing protection is improved, but not to as high a level as one might think.

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Finally, there are electronically-enhanced hearing protection devices, including specialized hearing aid/earplug combinations, and earmuffs fitted with external microphones and internal speakers. The sound system in electronic muffs allows the user to hear surrounding sounds at a normal levels, or even louder than normal. When a dangerously loud sound is detected by the electronics, the speakers to the ears are deactivated until the noise reaches a safe level again. Prices for these systems range from as little as $50 to thousands of dollars, depending on what you’re looking for.

A Personal Matter
When I was approached by Guns & Ammo to write this piece, I hoped they wanted me on the job because of my witty prose and unquenchable enthusiasm for shooting. But in the end, they just wanted me for my body. You see, I have a moderate-to-severe bilateral hearing loss of over 60 dB in the 500 to 2,000 hertz range, along with symptoms of tinnitus. That means I wear hearing aids in both ears to help me understand what people have to say, and I have ringing in my ears.

My hearing loss is genetic in nature, which means there was nothing I could have done to avoid it. It’s a little gift from my DNA that kicked in about 17 years ago, but the symptoms are just the same as those caused by loud noise exposure. I was careful to protect my hearing before the loss, but I’m religious about taking care of what I have left now.

Is the Tinnitus annoying? Yes, on good days it’s only annoying. Do I miss hearing and understanding what my wife, kids and co-workers have to say? Only when they choose to speak to me. Don’t the cutting-edge digital hearing aids help? Yes, and they’re a real bargain at $1,400-3,000 apiece, plus the cost of replacement every three years or so, batteries, maintenance, service charges, and hearing checks.

While it may be better to have loved and lost than to never have loved at all, I just can’t come up with any reason why losing hearing would be plus. Ear protection is far too easy to obtain and use for anyone to have a good reason to gamble with their hearing. So what is your hearing worth? The last I checked, you can start protecting it for as little as 25 cents (foam plugs) per trip to the range. Take it from me, it’s well worth the investment.

Medford Rifle and Pistol Club

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