|
|
June 16th, 2008
Your editor wins the dunce of the week award, but he learned an important lesson. This weekend I shot the Varmint Silhouette match at Ojai, California. In preparation for the match, I (wisely) went to a range on Thursday to chronograph my match load and confirm my 100-yard, no-wind zero. All went well there, and after three sighters I put three rounds into 0.260″ right at point of aim. So far, so good.
| Editor moves his scope AFTER zeroing. End result? Zero shifts 2 MOA up and 11.5 MOA right. Yikes! |
 But, while testing, I noted that the scope, having been positioned for prone shooting, was much too far forward. It needed to be moved back about an inch for comfortable shooting at the bench.
No problem I think… I take the gun home, get my Leupold Torx wrench and loosen the rings. Now, I use Burris Signature rings, the ones with the plastic inserts that provide elevation preload: +10 in the rear and a -10 in the front. These are net values, created with pairs of +05 (thicker) and -05 (thinner) half-ring inserts. In the back the thicker +05 insert is on the bottom and thinner -05 on top, while in the front the thicker insert is on the top with the thinner on the bottom.
First thing I note when moving the scope is that it was hard to set the inserts in exactly the same spot (though I tried). I also note that the inserts seemed to flatten out or squeeze down more when I re-tensioned the ring bolts.
I figured I might have to make a minor correction to my zero at the range, so I wasn’t too concerned. Boy was I wrong.
Windage off Six Feet at 600 Yards
At the match, I dialed in my 600-yard come-up and aimed at a steel gong we use for sighter shots. Normally I can “certify” my 600-yard zero in three shots. This time, my spotter couldn’t even see the hits. “WTF”, I think… Then another shooter notes that my bullets are impacting about SIX FEET to the right of the Gong and about a foot too high.
I had to dial in 46 clicks (11.5 MOA) of left windage to get back on the Gong. At 600 yards, one MOA is 6.282 inches. My 600-yard Point of Impact had shifted 72″ to the right — a full six feet! That’s huge. That’s like being off a foot at 100 yards.
LESSON LEARNED: If you make ANY change to your scope, you should re-zero.
SIGNATURE RING LESSON LEARNED: If you are running the Burris Signature Rings, with plastic inserts, the change in POI when you move the scope can be extreme — way more than you’d expect with conventional rings. The plastic inserts take a different “set” each time you tension the rings, even if you do your best to maintain the inserts’ orientation in the rings. No matter how careful you are, those plastic inserts aren’t going to hold the scope in exactly the same place.
So, if you don’t want to win the Dunce Award like I did, make sure you re-test your scope’s zero AFTER you move the fore-and-aft position, and EVERY time you re-tension Burris Signature Rings. It’s worth noting that the ring set in question is five years old and it held zero perfectly until I decided to move the scope back. This was done because my club recently built benches at the 600-yard line so we now shoot from the bench rather than prone, F-Class style.
June 12th, 2008
High-magnification scopes allow shooters to aim more precisely and to see their targets better at long ranges. Recent years have seen an “optics arms race” in benchrest shooting. It used to be thought that 36-power was plenty for 100- and 200-yard BR matches. Now, top shooters are running 40- or 45-power optics, and some competitors are even using 50X and 60X scopes.
Perils of Too Much Magnification
Extra magnification comes with a price, however. With equal-sized front objective lenses, the view through a 50-power scope will appear darker than the view through a 35-power optic, and the 50X will have a much smaller exit pupil. The exit pupils on some scopes are under 1mm. An exit pupil that tiny makes your head position ultra-critical — move your head very slightly and you’ll lose the circle of light entirely. Small exit pupils are more fatiguing, causing more eye strain. Higher magnification can, in some conditions, also make it more difficult to cope with mirage. Many shooters prefer a zoom scope so they can dial down the magnification when the mirage is extreme.
Advantages of Variable-Power Scopes
So how much magnification do you really need? That comes down to your personal preferences and your budget. Since a good zoom scope, such as the Nightforce BR 12-42×56 or the new Sightron SIII 8-32×56, lets you “back off” your power, there’s really no reason NOT to go with a high-power scope on a target rifle, provided you can make weight.
A Formula for Scope Resolving Ability
From an optics standpoint, how much power do you need to resolve a bullet hole at a given distance? There is a handy online Scope Resolution Calculator that lets you do this. Just type in the bullet diameter and distance, and the calculator will tell you how much magnification you need, at a MINIMUM, to resolve that particular size bullet hole. This calculator assumes perfect viewing conditions and the highest grade lenses. In reality, as viewing conditions get bad, all bets are off. A bullet hole that could be resolved at 30-power in perfect viewing conditions, might not be resolved even at 80-power when conditions are bad. Nonetheless, it’s fun to play with the calculator, created by Twin City Rod & Gun:
CLICK HERE for Bullet Hole Resolution Calculator
June 11th, 2008
While shooting at the Pala Varmint Silhouette Match recently, we had a chance to test drive John Adams’ Pentax PF-80ED Spotting Scope. It’s a great scope, fitted with outstanding lenses. We tried both the 20-60 power zoom and the superb Pentax XW-10 wide angle/extended eye relief lens, which provides a fixed 52X image. The XW-10 is the most user-friendly spotting scope eyepiece I’ve ever tried–ultra-bright, with nearly an inch of eye relief.
One thing that made the Pentax such a pleasure to use was the mounting set-up. John has his PF-80ED set on a sturdy Manfrotto tripod with a special geared tripod head, the Manfrotto model 410. The geared head allows you to make very fine, precise movements in vertical or horizontal planes. You don’t have to unscrew a clamp, fiddle around to re-position the scope, and then struggle to lock it in place again without altering the position. This unique, compact head offers precise gear movement in three directions: pan (horizontal movement left to right), elevation, and angular rotation around TDC (horizon tilt).
The Manfrotto 410 geared head was superb. While spotting at 600 yards, I could easily move up or down a few inches on the target with just a quick twist of a knob. If I wanted to move down the line to a sighter plate, it was just as easy to pan a few feet horizontally, without disturbing my vertical setting at all. I don’t know how Manfrotto does it (the gearing system is patented), but very little effort is required to turn the knobs in any direction, and there is plenty of travel.
If you want to make large adjustments, as when moving your view from a 1000-yard target bay back to the 100-yard line, you can disengage the gear drives and manually move the entire head. The Manfrotto 410 incorporates a unique feature that allows you to instantly disengage the gears and rough position the camera by hand, then instantly reengage them for precise final alignment. The model 410 head supports up to 5 kg (11 pounds), and is also suitable for 35mm SLR and medium format cameras. The head incorporates a quick release camera plate system.
So what does this superior technology cost? The Manfrotto model 410 costs about $210.00 at large camera outlets, but you can sometimes find one for about $180.00 on sale. Is it worth it? If you’re on a very tight budget–spend your money on a barrel first. But, if you have an $800+ scope that’s used quite often, the geared head is worth the investment. Others seem to agree — three other Pala shooters added geared heads to their tripods after trying John Adams’ rig. The gearing makes it much, much easier to move the scope in very small increments while spotting at extreme ranges. But what about resale? These geared heads are also extremely popular with commercial photographers, so they hold their value well.
The Manfrotto 410 was previously sold as a “Bogen-Manfrotto 3275/410″ and you may still find older versions listed that way. Manfrotto also makes two other geared heads, the model 400 ($680.00, 22 lb. rating) and 405 ($385.00, 16 lb. rating), but these are much more expensive, and designed for very heavy cameras.
Pipe and Post Level
To get the best results from any tripod when using a spotting scope (or chronograph), you need to make sure the base for your scope is set level to the horizon. Deluxe heads, such as the Manfrotto geared heads, have built-in bubble levels, which make it easy to level the scope. If you don’t have a level on your tripod, but it has a telescoping center shaft, you can use a simple, inexpensive Pipe and Post Level. These attach with an elastic band around the vertical shaft and provide bubble levels in both horizontal and vertical planes. You can purchase these levels for under $5.00 at hardware stores and home supply outlets.
Good, Inexpensive Tripod
If you want for a good, solid tripod that will hold a heavy 80+ mm spotting scope at a bargain price, look for a used Davidson Star-D on eBay, or one of the optics forums.
 The Davidson Star-D tripod is a solid, all-metal rig that is sturdy enough to be used for movie cameras. Star-Ds feature convenient rotary cam (collet) leg height adjustments and all-metal tilt and pan controls that lock solidly. The center post is clamped with a big locking ring that adjusts for tension. The rugged, machined-aluminum Star-D tripods are no longer in production but you can find good “previously-owned” models for sale on eBay. This tripod is ideal for use with a chronograph or spotting scope (for viewing in sitting or standing positions). You’ll see a variety of Star-Ds on eBay. What you want are the newer Star-Ds with all-silver heads and cam-locked legs. You can often pick them up for under $25.00. Look for the latest versions, as shown in the picture.
June 11th, 2008
Right now the March line of scopes represent the “state of the art” in high-magnification Benchrest scopes. They are unexcelled for brightness, sharpness, and perhaps most importantly, shot-to-shot reliability. Many top short-range benchrest shooters, who can’t tolerate even a tiny shift in the scope’s reticle moving the point of impact a few hundreths of an inch, are using the March 40X, 50X, and 60X, and now the new 10-60X Zoom.
CLICK HERE for complete MARCH SPECIFICATIONS
March scopes are made in Japan by DEON. In the USA they are sold exclusively by Kelbly’s. Jim Kelbly reports: “Some 40s and 50s are in stock now. The 10-60X zooms will be in stock in about two months unless the back order list gets longer as it is everyday. If you want a March scope you should not wait till they are in stock. We have a waiting list and you should get on it if you would like one in next two months.”
Current March Scope pricing:
40×52, 50×52, and 60×52 fixed focal length: $2100.00
10-60×52 Zoom: $2400.00
May 22nd, 2008
Jon Jackoviak of The Optic Zone reports that his first shipment of Bushnell Elite 6500 4.5-30×50 scopes has arrived. These come with a Fine Multi-X reticle and 1/4-MOA clicks, and are priced at $739.00. (A mildot reticle version may arrive in a few weeks.) Other dealers may be stocking this scope soon.
These scopes have been anxiously awaited, ever since they were announced at SHOT Show earlier this year. The 6.5x magnification range is the widest in the industry, and the scope’s 30mm main tube and side-focus parallax adjustment puts it in the running with Leupold’s 8-25×50 LRT. The new scope also features Bushnell’s patented, Rainguard® hydrophobic (water-repellant) lens coating. This coating prevents fogging by causing condensation to bead up into much smaller droplets.
The question mark remaining about the new Bushnell 6500 is the actual elevation range. The Optic Zone (and some other vendors) are claiming 80 MOA each of Windage and Elevation Adjustment, but the Bushnell website says there are only “50 inches” total Elevation on the 4.5-30×50. Right now we’re betting on Bushnell’s lower number, which is significantly less than the 75 MOA offered by the new Sightron 8-32×56, which we have confirmed.
May 15th, 2008
Creedmoor Sports has a new promotion for scope buyers. If you purchase a Nightforce NXS or Benchrest Model scope at regular price, Creedmoor will give you a $75.00 gift cerficate that can be applied to other Creedmoor Sports merchandise. (Note: The certificate can NOT be applied to the original scope sale, or the purchase of another Nightforce product.)
May 14th, 2008
Just this week, Sightron sent us one of the new Sightron SIII 8-32×56 LR D rifle scopes for evaluation. This new optic features a 30mm main tube and weighs 24.7 ounces. Clicks are set in 1/4-MOA increments. The reticle is a fine cross hair with 1/4-MOA dot. The scope comes with a 3″ sunshade, turret covers, and rubber-connected, see-thru lens caps. Jason Baney had a chance to test the scope and give his initial impressions of its optical qualities. We will follow this “First Look” report with more extensive testing of the scope’s mechanical tracking and long-range resolution.
Overall, Jason was extremely impressed with the new scope. It was very bright, with excellent color rendition and contrast. The image remained bright and sharp out all the way out to the edges, with no shadowing or distortion. Compared to a Nightforce 12-42×56 BR scope set at 32-power, Jason thought the Sightron had better contrast and more vivid colors. Jason concluded: “At this point, the new Sightron seems like a good value, and compares well with the Nightforce BR model.”
Parallax and Focus
Importantly, the Sightron’s parallax control worked perfectly. There was no lash issue and Jason was able to attain minimal parallax with the target at maximum sharpness. With some other scopes, if you set the scope to have the target in best focus, you’ll still have too much parallax.
Elevation and Windage
This is a scope you can use to 1000 yards. Jason ran the adjustments top to bottom and recorded 75 MOA of both Elevation and Windage, based on the stated 1/4-MOA click Value. (That’s 75 total MOA available from one extreme to the other.) The target knobs have 15 MOA per turn and operate VERY smoothly and positively. Jason said the clicks “feel similar to Nightforce NXS clicks, but the Sightron clicks engage with a slightly softer feel, with less resistance.”
 Resolution Tests
Jason used two resolution charts, the USAF 1951 Optical Chart, and a line-width/text size chart. To judge resolution, Jason did a comparison test of the new Sightron 8-32×56 and a Nightforce 12-42×56 BR, with both scopes set at 32x with their sunshade attached. Jason looked through both scopes at the resolution test targets at 100 yards, and then at target frames, grass, and flowers at 300 yards. Viewing was done late in the day, with some shadows on the range. Keep in mind these were less than ideal conditions for viewing.
The test charts have incrementally smaller focus lines and text. Both scopes were able to resolve down to the same line/text level on the two resolution charts. The new Sightron showed comparable, but VERY slightly less resolution than the NF. Both could identify the same size of text, but the NF saw it just a bit more crisply. Jason reports: “I could go to the same resolution level with both scopes, but the last line was just a touch more crisp with the Nightforce. Still, the Sightron is very close in resolution.”
Contrast and Color Fidelity
The Sightron was the winner in this category. In fading light, the Sightron delivered better contrast. Green, yellow, red, and white colors showed more differentiation and all the colors were more vivid. Weathered target backer boards also showed more contrast through the Sightron. Jason checked this several times nearing dusk, and the Sightron always seemed more vivid and showed more contrast looking at a patch of grass and colored vegetation. In terms of color temp, the Nightforce has a more whitish tone, whereas the Sightron seemed “warmer” with more vivid colors.
Brightness/Light Transmission
Along with its superior color and contrast, the Sightron seemed to be consistently brighter through the fading light. We note, however, that manufacturers’ published light transmission factors are nearly identical for the Sightron 8-32 and the Nightforce 12-42. The greater brightness of the Sightron is Jason’s subjective perception, but he said “the Sightron definitely seemed brighter.”
View to Edge
With many zoom scopes, at high magnification, the center of the “circle of light” is bright and sharp, but the edges are faded or shadowy. The brightness attenuates (fades out) on the edges. In addition, you sometimes see some image distortion or focus loss at the edges. The Sightron showed none of these issues. At SHOT show, this editor looked through a prototype 8-32 Sightron and it was bright and sharp all the way out to the edges. Jason observed the same thing: “The Sightron was noticeably clear edge to edge, where the Nightforce showed some fading or darkening at the edges. This point was quite surprising to me.” Jason also noted that the Sightron had about a 3-4″ wider field of view at 100 yards.
Fringe Effect with Highly Reflective Subjects
With the Sightron, when looking at extremely bright, reflective objects, such as a car’s chrome trim, Jason did observe some minor fringing–what he called a “thin halo”. This also appeared around the edge of a white target paper viewed in bright light. A through-the-lens photo appeared to show edging colors (purple fringe), so this may be Chromatic Aberration*. It wasn’t a major issue and it did not affect the sharpness or contrast of the viewed object itself. This was visible only on the periphery of very bright objects.
Conclusion–Impressive Optics for $825.00
We only were able to comparison-test one sample of each scope, Sightron vs. Nightforce. As noted, the performance was very close, and it is possible that different samples might perform slightly better or worse in each optical category. In this test the Nightforce had a very slight edge in resolution, while the Sightron was brighter. We plan to do more testing, with bullet-hole targets set at long ranges. That should give us a better sense of how the Sightron can resolve bullet holes and target lines out past 300 yards. Jason will also do a box-test to check the tracking and repeatability of the Sightron. Based on what we’ve seen so far, however, the Sightron, with a “street price” of about $825.00, is a very good value. Jason concludes: “Given the 8-32 Sightron’s price point, I’d say most people will feel it is a great scope for the money.”
*Chromatic aberration occurs in a riflescope when white light, bent by the objective lens, separates into different colors (wavelengths), each color bending at a slightly different angle. When that occurs, the colors don’t focus at the same point. This most often appears as a deep blue/purple or yellow edge on the image, particularly straight black and white edges.
May 8th, 2008
Newcon Optik, based in Toronto, Ontario, Canada, produces many optics products for the Canadian military including laser rangefinders, image stabilizers, and night-vision gear. Newcon Optik also sells a line of laser rangefinders for consumers. Newcon claims that its rangefinders offer performance comparable to Leica, but at a much lower cost. The Newcon Optik LRM2000 Pro is designed to function out to 2000 meters, with a “reliable, all-conditions range” of at least 1500 yards. The LRM2000 Pro sells for $499.95 at SWFA.com, making it considerably cheaper than comparable models from Leica and Swarovski.
AccurateShooter.com has not been able to field test the LRM2000 Pro ourselves. For that reason it was not included in our Review of Laser Rangefinders done in 2007. However, we’ve handled the unit at SHOT Show and there are many features we like. First, it has a selectable reticle, offering a choice between a small rectangle and a cross-hair. By contrast, the $890.00 Swarovski Laser-Guide only offers a rather large aiming circle. Some hunters have complained the Swaro’s reticle is just too big for deer-sized animals out past 600 yards or so.
FEATURES
1 – Measurement result
2 – Units of measurement (Yards, Meters, Mils, Degrees)
3 – Low battery indicator
4 – Over 100m indicator (LRM 2500, LRM 2500CI Models only)
5 – Laser active indicator
6 – Target quality indicator (optional)
7 – Reticle (cross or rectangular selectable)
We also like the Newcon Optik’s shape and ergonomics. Sized 4.72″ x 4.8″ x 2.36″, the Newcon is flat and easy to hold, with non-slip rubber grip sections on both left and right sides. You can hold the brick shape securely with two hands, horizontally, like using binoculars.
 By contrast, Leica went to an ultra-compact, vertical design for its latest CRF1200 rangefinder. The CRF’s small size makes the Leica easy to carry, but it is more difficult to hold the Leica stable when precise aiming is needed. With the Newcon Optik, you can set it flat on top of a case or rucksack and it’s easier to maintain a solid grip. The LRM2000 Pro also offers a built-in digital compass, a nice feature for anyone in the outdoors.
In the video below, Alex Rudi of Newcon Optik explains the features of the LRM2000 Pro model:
CLICK HERE to watch NEWCON OPTIK VIDEO
How do the Newcon Optik rangefinders perform in the field? Do they live up to the claims of Leica-class performance? We invite our readers who own or use Newcon Optik rangefinders to add their comments.
CLICK HERE for LRM2000 PRO SPECS SHEET (.pdf file)
April 3rd, 2008
Alan Orr at Sightron tells us that the much-awaited new Sightron scopes, including the 6-24×50 MilDot and 8-32×50 Target models, are scheduled to arrive in the first week of May. You may want to place orders with vendors soon to be assured of getting one from this shipment.
The new 6-24×50 SIII is an all-new 30mm scope that rivals the Leupold 8-25 LRT in design and performance. Available in target dot or mil-dot reticle, the 6-24x50mm offers a full 100 MOA of windage and elevation in a relatively compact (14.96″) scope weighing 21.90 ounces. Clicks are 1/4 MOA .
NEW 8-32x56mm with 70 MOA of Windage + Elevation
For long-range shooters, the most exciting new offering from Sightron is the SIII 8-32x56mm. This scope has more magnification and a larger front objective than the Leupold 8-25×50 LRT, but with an $825.00 estimated “street price”, the Sightron costs less. Initially, the Sightron 8-32×56 will be offered with 1/4 MOA clicks, and just one reticle, a target dot. Sightron has indicated that other reticles might be offered in the future.
CLICK HERE for Scope SPEC SHEET (MS Excel File)
March 17th, 2008
Here’s a good deal on a scope suitable for deer hunting and general field use. The magnification range is sensible for an all-around hunting rifle. SWFA is offering the 3-9×40 Team Primos Riflescope for just $199.00 (item 8435). That’s $150.00 off SWFA’s normal price, and $40-$50 cheaper than the best prices we’ve found at other vendors.
Weighing just 13 ounces, the Nikon offers near-constant 3.6-3.7 inch eye relief and 95% light transmission with full-coated lenses. The nitrogen-filled scope is 100% Waterproof/Fogproof/Shockproof and features a one-piece main body tube. Nikon offers a full, lifetime warranty.
The scope features Nikon’s BDC (Bullet Drop Compensating) reticle designed and calibrated to provide fast, simple aiming points for various shot distances. This system has a series of small “ballistic circles”-each subtending 2″ at 100 yards.
Nikon’s BDC is designed to be used with most standard centerfire cartridges with typical bullet weights, providing aiming points out to 500 yards, with a 100-yard sight-in. With Magnum cartridges and typical bullet weights, the same scopes with BDC reticles offer aiming points out to 600 yards, with a 200-yard sight-in.
|
