July 2nd, 2014

One Dollar Do-It-Yourself Mirage Shield

make your own mirage shield for rifleWant to shoot better scores at your next match? Here’s a smart, inexpensive do-it-yourself project from the good folks at Criterion Barrels. For less than one dollar in materials, in just a few minutes you can create a handy, effective mirage shield, custom-fitted to your favorite rifle.

All precision shooters should be familiar with mirage, a form of optical distortion caused primarily by variations in air temperature. Savvy shooters will use mirage as a valuable tool when gauging wind speed and direction. Natural mirage is unavoidable, but there are many techniques designed to limit its influence in long-range marksmanship.

make your own mirage shield for rifle

A form of mirage can be produced by the barrel itself. Heat rising from the barrel may distort sight picture through your optics, leading to erratic results. Mirage caused by barrel heat can be reduced dramatically by a simple, light-weight mirage shield.

How to Make a Mirage Shield

A mirage shield is an extremely cost-effective way to eliminate a commonly-encountered problem. Making your own mirage shield is easy. Using old venetian blind strips and common household materials and tools, you can construct your own mirage shield for under one dollar.

Materials Required:
1. Vertical PVC Venetian blind panel
2. Three 1”x1” pieces adhesive-backed Velcro
3. Ruler or tape measure
4. Scissors or box cutter
5. Pencil or marker

1. Measure the distance from the end of the receiver or rail to the crown of the barrel.

make your own mirage shield for rifle

2. Using a pencil and ruler, measure the same distance and mark an even line across the blind.

make your own mirage shield for rifle

3. Cut across the line using scissors or a box cutter, shortening the blind to the required length. (Remember, measure twice, cut once!)

4. Expose the adhesive backing on the loop side of the Velcro. Center and apply the Velcro strips on the barrel at regular intervals.

make your own mirage shield for rifle

5. Expose the adhesive backing of the fuzzy side of the Velcro.

6. Place the blind on the upper side of the barrel. Apply downward pressure. Once the Velcro has secured itself to the barrel, separate the two sides. Proceed to mold both sides of the Velcro to fit the contour of their respective surfaces.

7. Reaffix the blind. Barrel related mirage is now a thing of the past!

make your own mirage shield for rifle

How to Remove and Re-Attach the Mirage Shield
Removal of your mirage shield is accomplished by simply removing the blind. You can un-install the Velcro by pulling off the strips and then gently removing any adhesive residue left behind using an appropriate solvent. (Simple cooking oil may do the job.) Caution: With fine, high-polish blued barrels, test any solvent on a non-visible section of the barrel. Before storing the gun, re-oil the barrel to remove active solvents and residual fingerprints.

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June 29th, 2014

When Good Scopes Go Bad — Making the Difficult Diagnosis

Riflescopes are mechanical contraptions. One of the sad realities about precision shooting is that, sooner or later, you will experience a scope failure. If you’re lucky it won’t happen in the middle of a National-level competition. And hopefully the failure will be dramatic and unmistakable so you won’t spend months trying to isolate the issue. Unfortunately, scope problems can be erratic or hard to diagnose. You may find yourself with unexplained flyers or a slight degradation of accuracy and you won’t know how to diagnose the problem. And when a 1/8th-MOA-click scope starts failing, it may be hard to recognize the fault immediately, because the POI change may be slight.

When An Expensive Scope Goes Bad
Recently, this editor had a major-brand 8-25x50mm scope go bad. How did I know I had a problem? Well the first sign was a wild “drop-down” flyer at a 600-yard match. After shooting a two-target relay, I took a look at my targets. My first 5-shot group had five shots, fairly well centered, in about 2.2″. Pretty good. Everything was operating fine. Then I looked at the second target. My eye was drawn to four shots, all centered in the 10 Ring, measuring about 2.4″. But then I saw the fifth shot. It was a good 18″ low, straight down from the X. And I really mean straight down — if you drew a plumb line down from the center of the X, it would pass almost through the fifth shot.

That was disconcerting, but since I had never had any trouble with this scope before, I assumed it was a load problem (too little powder?), or simple driver error (maybe I flinched or yanked the trigger?). Accordingly, I didn’t do anything about the scope, figuring the problem was me or the load.

Riflescope Repairs

But, at the next range session, things went downhill fast. In three shots, I did manage to get on steel at 600, with my normal come-up for that distance. Everything seemed fine. So then I switched to paper. We had a buddy in the pits with a walkie-talkie and he radioed that he couldn’t see any bullet holes in the paper after five shots. My spotter said he thought the bullets were impacting in the dirt, just below the paper. OK, I thought, we’ll add 3 MOA up (12 clicks), and that should raise POI 18″ and I should be on paper, near center. That didn’t work — now the bullets were impacting in the berm ABOVE the target frame. The POI had changed over 48″ (8 MOA). (And no I didn’t click too far — I clicked slowly, counting each click out loud as I adjusted the elevation.) OK, to compensate now I took off 8 clicks which should be 2 MOA or 12″. No joy. The POI dropped about 24″ (4 MOA) and the POI also moved moved 18″ right, to the edge of the target.

Riflescope RepairsFor the next 20 shots, we kept “chasing center” trying to get the gun zeroed at 600 yards. We never did. After burning a lot of ammo, we gave up. Before stowing the gun for the trip home, I dialed back to my 100-yard zero, which is my normal practice (it’s 47 clicks down from 600-yard zero). I immediately noticed that the “feel” of the elevation knob didn’t seem right. Even though I was pretty much in the center of my elevation (I have a +20 MOA scope mount), the clicks felt really tight — as they do when you’re at the very limit of travel. There was a lot of resistance in the clicks and they didn’t seem to move the right amount. And it seemed that I’d have four or five clicks that were “bunched up” with a lot of resistance, and then the next click would have almost no resistance and seem to jump. It’s hard to describe, but it was like winding a spring that erratically moved from tight to very loose.

At this point I announced to my shooting buddies: “I think the scope has taken a dump.” I let one buddy work the elevation knob a bit. “That feels weird,” he said: “the clicks aren’t consistent… first it doesn’t want to move, then the clicks jump too easily.”

Convinced that I had a real problem, the scope was packed up and shipped to the manufacturer. So, was I hallucinating? Was my problem really just driver error? I’ve heard plenty of stories about guys who sent scopes in for repair, only to receive their optics back with a terse note saying: “Scope passed inspection and function test 100%. No repairs needed”. So, was my scope really FUBAR? You bet it was. When the scope came back from the factory, the Repair Record stated that nearly all the internal mechanicals had been replaced or fixed: “Replaced Adjustment Elevation; Replaced Adjustment Windage; Reworked Erector System; Reworked Selector; Reworked Parallax Control.”

How to Diagnose Scope Problems
When you see your groups open up, there’s a very good chance this is due to poor wind-reading, or other “driver error”. But my experience showed me that sometimes scopes do go bad. When your accuracy degrades without any other reasonable explanation, the cause of the problem may well be your optics. Here are some of the “symptoms” of scope troubles:

1. Large shot-to-shot variance in Point of Impact with known accurate loads.
2. Uneven tracking (either vertical or horizontal).
3. Change of Point of Impact does not correspond to click inputs.
4. Inability to zero in reasonable number of shots.
5. Unexpected changes in needed click values (compared to previous come-ups).
6. Visible shift in reticle from center of view.
7. Changed “feel” or resistance when clicking; or uneven click-to-click “feel”.
8. Inability to set parallax to achieve sharpness.
9. Turrets or other controls feel wobbly or loose.
10. Internal scope components rattle when gun is moved.

Source of Problem Unknown, but I Have a Theory
Although my scope came with a slightly canted reticle from the factory, it had otherwise functioned without a hitch for many years. I was able to go back and forth between 100-yard zero and 600-yard zero with perfect repeatability for over five years. I had confidence in that scope. Why did it fail when it did? My theory is side-loading on the turrets. I used to carry the gun in a thick soft case. I recently switched to an aluminum-sided hard case that has pretty dense egg-crate foam inside. I noticed it took some effort to close the case, though it was more than big enough, width-wise, to hold the gun. My thinking is that the foam wasn’t compressing enough, resulting in a side-load on the windage turret when the case was clamped shut. This is just my best guess; it may not be the real source of the problem. Remember, as I explained in the beginning of this story, sometimes scopes — just like any mechanical system — simply stop working for no apparent reason.

Permalink - Articles, Optics 6 Comments »
June 26th, 2014

Optics Terminology — Lessons from Swarovski Optik

Swarovski Optik exit pupil scope accurateshooter.comWhen shopping for a new riflescope or spotting scope it’s easy to get confused by all the technical terminology. Do you wish you had a better way to compare scopes — beyond just size, weight, and price? Well Swarovski Optik can help. The Swarovski Hunting Blog offers a helpful guide to technical terms used when comparing scope specifications. Here are some important definitions, expressed in layman’s language:

Objective Lens Diameter
The objective lens diameter determines the size of the optical system’s entrance pupil. The bigger the objective lens diameter, the more light the system can capture. However, the size of the objective lens does not determine the size of the field of view.

Exit Pupil
The size of the Exit Pupil is determined by the objective lens diameter and the magnification. If you look at the eyepiece from a distance of around 30 cm (11.8 in), the Exit Pupil appears as a bright disc.

For calculating the Exit Pupil the formula is:

Exit Pupil = objective lens diameter ÷ magnification (expressed in power number).

The larger the Exit Pupil, the more light will reach the eye.

Swarovski Optik exit pupil scope accurateshooter.com

Field of View
The Field of View is the size of the circular section of the area which can be observed when you look through a long-range optical device. In the case of rifle scopes, it is specified at a distance of 100 meters or 100 yards. For example, 42.5 m at 100 m or 127.5″ at 100 yards. As an alternative, the Field of View can also be stated in degrees (e.g. 6.6°).

NOTE: The technically-feasible size for the Field of View is essentially determined by the magnification. The higher the magnification the smaller the Field of View.

Swarovski Optik exit pupil scope accurateshooter.com

Twilight Factor
The Twilight Factor defines the optical system’s performance in poor light. The statement “the greater the twilight factor, the better the suitability for twilight” only applies if the exit pupil is larger than or at least as big as the eye’s pupil. The pupil in the human eye can only open to around 8 mm. As we get older, our eyes become less flexible, which limits our ability to see things in twilight or at night. Therefore [an optic's] exit pupil cannot always be fully utilized.

For calculating the Twilight Factor the formula is:

Twilight Factor = root of ( magnification x objective lens diameter ).

NOTE: Spotting scopes have extremely high twilight factors because of their high magnification and large objective lens diameter. But [when used at high magnification] their small exit pupil can make them [somewhat difficult] to use in twilight.

CLICK HERE to Read Full Article (with more illustrations).

Photos copyright Swarovski Optik Blog, all rights reserved.

Story Tip by EdLongrange. We welcome reader submissions.
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June 10th, 2014

Save Fifty Bucks on Zeiss TERRA Scopes or Binoculars

Father’s Day (Sunday, June 15) is right around the corner. If dad enjoys hunting, here’s a way to save fifty bucks on a nice gift for the old man. Now through June 15, 2014, Zeiss is offering a $50.00 rebate on the TERRA 3X series rifle-scopes or TERRA ED Binoculars. The scopes offer 1/4-MOA clicks with a choice of standard Z-Plex or RZ6 or RZ8 ballistic reticles. Pick your power: 2-7x32mm, 3-9x42mm, 4-12x42mm, 3-9x50mm, and 4-12x50mm. CLICK Here for more details.

If you’re wondering about these binoculars, trust us, they are high quality. TERRA ED Binoculars feature SCHOTT ED glass — just about the best you can get. These binocs, in 8x42mm or 10x42mm versions, offer great low-light performance and a wide-angle field of view.

Zeiss Father's Day Sale

Zeiss Father's Day Sale

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May 22nd, 2014

Ring Inserts Adapt 1″-Diameter Scopes to Fit 30mm Rings

Brownells Ring ReducersForum member Jacob spotted this simple, but effective set of scope ring inserts on the Brownells Website. With these inserts, you can use a scope with 1″-diameter main tube in 30mm rings. Non-marring, matte black Delrin sleeves surround the scope tube so it can fit larger-diameter rings. Each sleeve comes in two parts for easy installation around your scope tube. This way you can use the same 30mm rings for all your scopes.

Ring Reducers are sold as front/rear kits. Cost is just $19.99 for the 1″ to 30mm converters, item 084-000-091. There are also sets that reduce 30mm rings to 25mm, and 1″ rings to 3/4″ or 7/8″.

Note: These Brownells units simply function as plastic bushings. Unlike Burris Signature Ring inserts, they do not allow you to “pre-load” windage or elevation. If your rings are misaligned, the Brownells Ring Reducers won’t correct that problem.

Permalink Gear Review, Optics 3 Comments »
April 27th, 2014

How (and Why) To Use Binoculars with a Tripod

Everybody knows that powerful spotting scopes work best when mounted to a stable tripod or otherwise secured to a steady mount. Yet when most folks use binoculars, they never even think of using a tripod, despite the fact that tripod adapters are available for many premium binoculars. A serious hunter should learn how to glass with tripod support. With binoculars offering more that 8X magnification, you can really benefit from a steady mount. In this article, Mark Boardman of Vortex Optics, an experienced hunter, explains the benefits of using a tripod with high-magnification binoculars.

Vortex Binoculars

READ FULL ARTICLE with More Tips for Hunters

Vortex Binoculars

Story tip by EdLongrange. We welcome reader submissions.
Permalink Hunting/Varminting, Optics No Comments »
April 22nd, 2014

Huge Discounts on Weaver Scopes at Natchez Shooters Supplies

Looking for a good, solid scope for your hunting or varmint rifle, but don’t want to spend more than $400.00? Here’s your opportunity. Natchez Shooting Supplies just slashed prices on the Weaver Classic Extreme Series of rifle scopes. This is a major price cut. Scopes that previously retailed for $500 or more are now being sold for $300-$350.00. Here’s an example, the Weaver Classic Extreme 8-32x50mm is going for $499.99 on eBay but Natchez has it for $349.95. And the Weaver 4-16x50mm Classic Extreme scope is now just $299.95, also marked way down from the original $500+ price. These scopes offer 30mm maintubes, 95% light transmission, multi-coated optics, and fast-focus eyepieces.

Quantities are limited and prices are subject to change. CLICK HERE for Natchez Sale Inventory.

Natchez Weaver Optics Sale

Sale Tip by EdLongrange. We welcome reader submissions.

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April 18th, 2014

Cool Integrated Optics Mount for under Ninety Bucks

AR skeletonized Warne AR MountHere’s a cool new optics mount at a very attractive price — just $87.95. Midsouth Shooter’s Supply is now featuring the Warne Skeletonized integrated scope mount for Picatinny Rails. This should work great on flat-top ARs. And for you fashionistas out there, the Warne mount is offered in four different colors: Matte Black, Dark Earth (tan), Ruby Red, and Bold Blue. Tactical shooters will probably pick black or tan sets, while image-conscious 3-Gun competitors might favor the Red or Blue versions.

These Warne integrated ring/mount sets are offered for 1″, 30mm, and 34mm rings. The 1″ and 30mm versions come in all four (4) colors and cost $87.95. The 34mm is offered in Matte Black only for $115.00. You may want to order soon. These are popular. The most popular colors (black and dark earth) could sell out quickly at this price.

AR skeletonized Warne AR Mount

AR skeletonized Warne AR Mount

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April 16th, 2014

Horus Video Explains Sources of Zero Shift in Rifle Scopes

YouTube Preview Image

In the above video, a spokesman for Horus Vision explains how and why scopes can experience zero shift. First, just cleaning the gun can cause a small shift in point of impact. Second, when you re-tighten rings and ring bases, this can cause a change in zero. Horus recommends that you use a torque wrench to confirm that you maintain the same torque settings each time. The same goes for action screw tension — tensioning your action screws can shift the point of impact.

Other factors that can cause a change in zero:

Temperature
Dramatic ranges of temperature will change your zero, because the air density affects the velocity of the bullet. With increased temperature, there may be a higher velocity (depending on your powder).

Gun Handling and Body Position
You rifle’s point of impact will be affected by the way you hold the gun. A “hard hold” with firm grip and heavy cheek weld can give you a different POI than if you lightly address the gun. Even when shooting a benchrest gun, the amount of shoulder you put into the rifle can affect where it prints on paper.

Type of Rifle Support — Bench vs. Field
Whenever you change the type of rifle support you use, the point of impact can shift slightly. Moving from a bipod to a pedestal rest can cause a change. Similar, if you switch from a mechanical rest to sandbags, the gun can perform differently. That’s why, before a hunt, you should zero the gun with a set-up similar to what you would actually use in the field — such as a rucksack or shooting sticks.

shooterXbag.com sandbag

Transportation of Firearms
Even if you don’t mishandle your weapon, it is possible that a shift of zero could occur during transport. We’ve seen zero settings change when a tight plastic gun case put a side load on the turrets. And in the field, if the turret knobs are not covered, they can rub against clothing, gear, storage bags, scabbard, etc. If the knobs turn, it will definitely move your reticle slightly and cause your point of impact to be off.

Permalink - Articles, - Videos, Optics 1 Comment »
April 15th, 2014

Field Test of Nightforce SHV by LongRangeHunting.com

If you’ve been considering the new Nightforce SHV scope for a hunting application, head over to LongRangeHunting.com. There you’ll find an in-depth field test of the 4-14x56mm SHV by Nicholas Gebhart. This is a very thorough review — Gebhardt checks every feature of the scope and comparison tests the SHV against the more costly Nightforce NXS 3.5-15x50mm. Gebhardt even put the SHV scope in his freezer for a weekend to ensure there was no fogging.

CLICK HERE for Product Specs and/or to Pre-Order Nightforce NXS.

NXS SHV scope review long range huntingOverall, Gebhardt was very pleased with the SHV: “Optical clarity, image brightness, contrast and resolution were all extremely good.” The tester also liked the MOAR reticle in his scope. He didn’t think it was too “busy” though he thought the hold-over lines would benefit from numbers: “Nightforce’s MOAR was easy to use and provided a clear sight picture for engaging small targets. The line thickness is perfect for both precise shot placement and visibility. My personal preference however would be for the even hash marks to be numbered for the entire lower portion of the reticle.” Gebhart noted that the SHV’s side parallax knob had yardage marking numbers that proved accurate (and handy to use) — most other scopes just have lines.

Nightforce SHV vs. Nighforce NXS
How did the new SHV stack up against the NXS in a side-by-side comparison? Gebhardt was impressed with the $995.00 SHV, saying it held its own with the pricier NXS model: “I took about 30 minutes to evaluate the optics of the SHV and see how it compared to an older Nightforce NXS 3.5-15X50. Both of these scopes are made in Japan but given the price differential, I expected to see some difference in the optical quality. To my surprise, I couldn’t find any optical difference between the two except for a very slight possibility of a brighter image with the SHV.”

Nicholas Gebhardt longrangehunting.com Nightforce SHV review

CLICK HERE to Read Full Nightforce SHV Scope Review.


Nicholas Gebhardt has been an active hunter primarily pursuing mule deer, antelope, coyotes and prairie dogs since he was old enough to legally hunt. Nicholas is also a precision rifle competitor and a Captain in the Montana National Guard.

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March 23rd, 2014

Big Sale on Nightforce Scopes at Lilja Precision Rifles

Need a first-rate scope for you new rifle? How would you like to get a Nightforce for a great price? Well, you’re in luck. Lilja Precision Rifles (“Lilja”) has placed its entire inventory of late-model Nightforce scopes on sale. The reason is that Lilja has decided to stop selling scopes and focus on its primary barrel-making business. Dan Lilja says that: “We have been a Nightforce dealer since Nightforce’s first year in business. But we’ve made the decison to leave the scope-selling business… and concentrate on our barrels. That part of our business is excellent and taking all of our time.”

Nightforce sale optics discount lilja barrels

Show below are the scopes on sale with regular price and sale price. Quantities are limited and these scopes are being sold “First Come, First Serve”. Prices are limited to stock on hand and do not include shipping. Scopes are not returnable – all sales final.


Nightforce sale optics discount lilja barrels

Lilja explains that some of these prices are well below MAPP (Minimum Advertised Price Policy) because they are for discontinued products. From time to time, Nightforce changes reticle combinations (or other features) and an product number (sku) becomes obsolete. Lilja also has some optics accessories for sale, such as rings and bases, PC programs, torque wrenches and other small items. Call (406) 826-3084 for availability or visit Lilja Precision Rifles.

Sale tip from EdLongrange. We welcome reader submissions.
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January 30th, 2014

Big Sale on Nightforce Scopes at Bullets.com

nightforce scope discount saleNightforce makes great scopes — just ask the man who owns one. Here’s your chance to get a Nightforce NXS, Benchrest, or Competition scope at a big discount. Bullets.com has acquired a large selection of 2013-model Nightforce scopes, and these are now being offered at sale prices. You can save hundreds of dollars on a scope (compared to original retail prices). For example the 5-22x56mm NXS is on sale for $1495.00. This same 2013 optic retails elsewhere for $1830.00 or more. The 2013 15-55x52mm Competition scope is $1840.00. Compare that to $2352.00 for a 2014-edition 15-55 Comp scope.

These special offers are limited to scopes in inventory. When they’re gone, they’re gone. When shopping online, go to the Bullets.com Nightforce Promo Page, and click on a particular model. In the detail page that opens you will see full specifications, including objective size, turret click value, and reticle type. Here are the specific Nightforce scopes on sale at Bullets.com:

nightforce scope discount sale

Before placing your order with Bullets.com, be sure you are 100% certain about the model you are ordering. Some scopes with the same magnification range come with a choice of either 50mm objective or 56mm objective. Likewise, there are various reticles offered for each basic model, and Nightforce offers 1/4 MOA clicks on some scopes, with 1/8 MOA clicks on others.

Permalink Hot Deals, Optics 4 Comments »