The Leupold name has been tied to quality American made optics for decades. Even more importantly, the Leupold name has been tied to tactical rifle scopes all the way back to the 1980s at the start of the tactical scope revolution. Their Mark 4 series of scopes helped define the genre and many versions of the Mark 4 scopes have now come and gone. Leupold recently dropped the Mark 4 line as a regular consumer model, but that does not mean they have exited the tactical rifle scope market, in fact, that could not be further from the truth. Leupold continues to evolve their lineup and introduce new scopes and one of those higher end tactical scopes is the subject of our review here. The Mark 6 series of scopes might seem like a competitor to their Mark 8 scopes, but that is not true as the scopes are aimed at different mission profiles and purposes and each is specifically designed to fill a need. For our review, we have the 3-18x44m version of the Mark 6 scope to see just how well it accomplishes the role of compact, high power, and extremely capable tactical rifle scope.
The Mark 6 arrives in the traditional Leupold box and includes a user manual, reticle diagram with description as well as a set of flip up scope caps, a sticker, Allen wrench and NRA signup card. There is no warranty card included as it has the traditional Leupold forever warranty that is valid whether you are the original owner or not and does not require registration. There is nothing new in the box that we have not seen before and of course on the bottom of the scope there is the familiar, and welcomed, tag line “USA * Designed * Machined * Assembled”. Leupold takes being made in America seriously and this was very apparent when we visited their factory earlier this year. While being made in America does not automatically make their scopes better, but it does mean any warranty and service happens at the same place where you place your phone call and there is a comfort level in knowing their optics are made by people who live and breath this stuff.
As we start looking at the Mark 6 scope we are immediately presented with something a little different than what we normally see on Leupold scopes. Once again we have a slow focus eyepiece with a locking ring, which has been the Leupold way of doing the adjustable diopter for years. Only this time the locking ring is very thin with very minimal knurling on it and it is the same diameter as the eyepiece housing making it very hard to grip, especially with gloves on. With our particular test scope, the locking ring really doesn’t matter as the eyepiece itself is extremely stiff and very difficult to move. There is so little purchase area for which to grab it with your fingers that your fingers end up sliding a lot more than the eyepiece actually moves. It is a good thing the diopter needs to be adjusted so infrequently because all of this combines to make adjustments difficult.
The eyepiece itself is long and large and a good portion of that length is the actual zoom power ring. The ridges on the zoom power ring that act as a gripping area are 1.3″ (33mm) long providing a lot of gripping surface and where those ridges end is where the zoom power markings are printed. These markings are slanted nicely toward the operator to make them easy to read from behind the scope. The little triangle indicator mark is located in front of the zoom ring which means it is completely shielded from view by the larger zoom ring. This is not too much of a concern as it is located directly on top of the scope and it is easy to estimate accurately what zoom power the scope is set at. Having the reticle in the first focal plane makes it non critical as well. Everything that was said about the adjustable diopter being difficult to adjust is the opposite for the zoom adjustment. It is easy to grip and smooth, yet just firm enough to require dedicated intention in order to adjust it.
The Mark 6 scope has a 34mm tube which provides durability and especially additional internal adjustments over a 30mm tube. There is 2.5″ (63.5 mm) of tube length in front of the zoom control ring for which to mount the rear scope mounting ring. The shoulder that houses the scopes primary control knobs is a rounded design of fairly low height, which is good considering the larger size of the 34mm diameter tube. There is a small flat face to the shoulder where the direction and indicator marks are located.
The elevation knob is a low profile, large diameter knob with some interesting and unique features to it. The knob is calibrate in MILs with each click representing .1 MIL of elevation adjustment. The knob has 10.5 MIL of adjustment per revolution, which is a lot and is also odd in that it is not an even amount per revolution. 10.5 MILs allows a standard .308 rifle shooting 175gr HPBT ammunition to get from 100 to 950 yards in just a single revolution in standard atmospheric conditions. Once the knob leaves zero a small metal protrusion sticks up half way indicating the scope is on its first revolution. This protrusion extends higher on its second revolution providing a good visual indicator of how many revolutions have been dialed in. Once the second revolution begins the operator can then utilize the second set of markings on the top of the knob which correctly align with the proper MIL reading. The offsetting of the dial on the second revolution is a bit odd, but it does function just fine and it allows for keeping the second set of numbers clear of the first for easy reading, though one may inadvertently confuse the two with a casual glance.
The elevation knob also features a zero stop as well as a zero lock. The zero stop operates just like we have come to expect from the zero stop feature on a scope and the zero lock actually locks the elevation knob on zero. In order to move the knob off of the zero setting, a button located on the elevation knob and positioned above the zero mark must be pressed and then the knob can be rotated. This zero lock only locks the knob when it is bottomed out at zero, it will not lock when the elevation knob passes the zero mark when passing through a full revolution of up. This zero lock works easy enough and it does keep the dial from inadvertently moving from your zero location while in transit or when crawling or doing other things that can move the knob.
Leupold indicates that the Mark 6 3-18x44mm scope has 100 MOA (29 MIL) of total elevation adjustment but the knob itself has a hard stop at 20 MIL preventing any further elevation from being dialed in. During our testing on several different rifles with tradition rings, canted bases, SPUHR mounts, and others, there was never a problem of running out of elevation when slipping the knob to zero and then having the full 20 MIL of adjustments available. 20 MIL is enough to take a 338 Lapua using 250gr bullets from a 100 yard zero to over 1600 yards and the 300gr 338 Lapua to about 1800 yards. Having 10.5 MILs per revolution means the clicks are packed in pretty tight meaning there is not much space between each click. Occasionally the operator may dial in a few extra clicks than was intended which happened a few times during our testing, but the clicks are pretty well defined and have an audible click sound. The knob is easy to grip and we like the low profile design.
The windage knob has a dust cap that can be utilized, or not, which is a nice option to have. There is the same 10.5 MIL of adjustment per revolution, but there is a hard limit at 5 MIL in each direction and the knob will not adjust past that 5 MIL. 5 MILs will be enough to shoot a 308 175gr in a direct crosswind at ranges beyond the capability of the 308 and is plenty of adjustment for even a 338 Lapua 300gr to shoot in 10 mph crosswinds at over a mile. The numbers count up in both directions and there is a L or R next to the number for a clear indicator of what windage you have dialed in. The clicks are the same as found on the elevation knob and the knurling at the top provides a good gripping surface.
On the opposite side of the windage adjustment is the knob with both the illuminated reticle adjustments as well as the adjustable objective (focus) knob. The focus knob is the control closest to the tube and has a range of markings from 75 yards to 500 and then infinity. This is one of the Leupold scopes that actually has number markings and not just different sized dots. The interesting thing is that the control actually goes from about 50 yards to a distance that is considerably further than the infinity sign on the knob. The entire range covers about 1/3 of the circumference of the knob. There is some tall knurling on the focus control which provides easy access to adjusting it and the knob rotates smoothly through the range.
The reticle illumination control is on the top of the knob and it has 7 brightness levels which is less than most scopes, but is enough for all practical uses. There is an off setting between each brightness level allowing for selecting your desired brightness level and then using the off setting next to it making it quick and easy to get right back to your desired setting. Having only 7 settings to span the entire rotation of the knob allows for wide spacing and very pronounced clicks. There is no question when each setting has been reached. The battery housing is on the top of this knob and is accessed via a hinged door on top that is opened by pressing a recessed release button.
In front of the shoulder of the scope is a shorter 1.84″ (46.7mm) length of tube in which to locate the forward scope mounting ring and then the tube tapers sharply into the bell housing of the scope. The bell housing itself is also short and the overall length of the scope ends up being a fairly compact at only 11.9″ (302mm). The 34mm tube adds weight and bulk to the scope which weighs in at 23.6 ounces, almost a pound and a half. The scope is solid and well built as you would expect from a $4400 scope. There is a lot of features and capability packed into a scope under a foot long. The markings are mostly subdued, though there are a lot of big L’s printed in various locations on the scope.
The optics on the Mark 6 are the best that Leupold has available with their latest Diamondcoating applied and all of their other features. The image is in fact bright and clear at all magnification settings and from edge to edge and we could find no faults with the optical quality. It is easy to focus the scope and get a good crisp image at any of the distances we engaged targets at. The reticle is the Horus TREMOR 2 that provides many reference points for which to hold off and engage targets with. It is certainly a busy reticle below the main horizontal stadia but this style reticle can be used effectively and has grown in popularity. The reticle is also located on the first focal plane so it grows and shinks with the magnification changes and Leupold has done a good job of sizing the reticle so that it is visible at all magnification settings yet is not too large at its highest 18x setting.
For our practical shooting tests we mounted this scope on a couple of different weapons systems and used it across many different engagement scenarios. For our objective testing we used our typical 700P test mule rifle and mounted it on a 20 MOA canted Warne steel base and used a set of Nightforce Ultralite 34mm rings. Once the scope was mounted we headed to the range and conducted our normal battery of tests on the scope. The weather was chilly at 30 degrees Fahrenheit but with very calm winds of 0-2 mph and with light high altitude clouds.
The box test results were very good with each group tracking nicely and printing on all the corners of the box and the last one being right on top of the first. The tracking proved excellent, but that is no surprise with modern optics. It was time to test the click sizes in a real world application and since this scope has MIL adjustments on it, we went with using a 6 MIL test. Since the scope has a hard 5 MIL lock on the windage knob, we first dialed in 1 MIL of right to fire our first group and then dialed in 6 MIL of left, which put it right at the 5 MIL stop, to fire the second group. The first group was well under .5″ in size and the second group was right about .8″. Of course we dialed the 6 MIL of right back in and fired another round to be sure the repeatability of the adjustments was good, and it went right into the first group. But something was off, the distance between the two groups seemed larger than 6 MIL and when we measured it, it confirmed our suspicion. At 100 yards 6 MILs equates to 21.6″ and the measured distance between the groups was 23.05″. For this test we allow for some error because we cannot be as precise measuring when the group sizes have variance in them. So we consider 5% of error to be a passing grade and under 3% of error to be right on. The adjustments on this scope came in with 6.7% of error which really surprised us and is what we would consider a failing score. This surprised us enough that we went back to our box test and measured the sides of the box and sure enough, the average box sides was also about the same percentage of error larger than they should have been.
To put this into practical perspective. If a 308 rifle with this scope was zeroed at 100 yards and then went to a 1000 yard target, one would expect to dial in 11.5 MILs of up elevation in standard atmospheric conditions which would compensate for the roughly 414″ of drop. With a 6% larger click than it should be, the scope would compensate with 439″ putting the impact 25″ higher than expected and potentially off the target. That is a big difference and is why this test is important.
The final two objective tests we perform are to test the scope for reticle drift while adjusting the zoom power through its entire range as well as with the focus. Reticle movement during these tests show up if the scopes are not well designed or poorly manufactured. Testing the zoom power first resulted in a rock solid reticle with no discernible movement as we cycled through the entire range. We then switched to the more difficult test with the adjustable objective. This test resulted in a very minute amount of up/down movement as it traversed the entire focus range. We would estimate the movement to be about .15 MIL through the entire 50 yard to infinity range which will result in little to no noticeable impact on practical performance. Remember that it is very rare to go from a 50 yard focus out to infinity and with some of that movement happening from 50 – 100, the effects are minimized even more when focusing from 100-1000+.
For our long range practical testing we mounted the Mark 6 onto a GA Precision 308 rifle using a SPUHR mount and used this rifle and scope combo for extensive testing and evaluating during some of our shooting classes as well as other long range shooting sessions. The scope performed very well, though we were unaware of the click size discrepancy at the time of our testing and we were using the reticle to engage as well as engaging a target and then adjusting as needed. We were not paying attention to what our click counts were compared to other scopes using the same rifle and ammo combo. The scope was a hit and was loved my most everyone who tested it and used it. The combination of size versus capability was a very positive aspect of this scope and the combination of tactical oriented features really made the scope rate highly with operators.
To conclude, the design, features, and size of the scope are excellent with durability and usability tailored to tactical use. The optical quality is also excellent and we loved using the scope. The one big problem we ran into on our test scope was the click sizes and we would certainly send the scope back in to Leupold to have it addressed before utilizing it on an every day long range rifle. Of course, if all of the gathered log data was done using only this scope then it would likely work out just fine as is, but those click sizes should not be off like they are. This is an expensive scope at over $4400 and Leupold support and service is legendary and they would take care of any issues without question. Unfortunately the problem came up during our testing and will be a mark against it for the time being. It is an excellent scope otherwise.