Cold Shot LLC – M.O.A.B/M.R.A.B

Watch the Installation Instruction Video

Download the PDF Installation Instructions for the M.O.A.B./M.R.A.B 4 Generation

The mounting process is a relative easy one. Used in conjunction with the dovetail design of the Picatinny rail there are 3 cross bolts that secures the M.O.A.B/M.R.A.B to the Picatinny rail. In the mounting process these bolts must first be removed, then the M.O.A.B/M.R.A.B can be slid into place from either end of the Picatinny through the dovetail. Once that has been accomplished the scope rings should be mounted on the scope followed by positioning the scope for the proper eye relief. The cross-bolts are then lined up with the slots of the Picatinny and tightened down to a torque of 8 ft. lbs. dry, or 6 ft. lbs. lubed. The top surface of the M.O.A.B/M.R.A.B replicates that of the Picatinny rail and as such will accommodate any of the Picatinny or  Weaver style scope rings

I chose to mount the M.O.A.B/M.R.A.B on a rifle known for its accuracy – a Savage Model 12 bolt-action and chambered in a cartridge that is phenomenally growing in popularity both by long-range target shooters and by varmint hunters – the 6.5 Creedmore. That combination seemed to be the perfect choice for evaluating the potential of the M.O.A.B./M.R.A.B system. The relative light recoil and flat trajectory of the Creedmore makes it a fine choice for critters like long-range prairie dogs and ground squirrels and the high ballistic coefficient, heavier weight bullets possess plenty of whop to bring the largest of predators quickly to the ground. The rifle came stock with standard 2-piece scope bases, which were of no use in this particular application. So, I contacted Savage and a few days later I received a Picatinny rail possessing the proper screw pattern for the rifle. Mil-STD-1913A Picatinny rails can also be purchased from various sporting outlets like Brownell’s, Midway USA, Evolution gun works, Burris. To top the M.O.A.B/M.R.A.B off I mounted a Leupold M8 12x40mm Standard scope using Leupold QRW (quick release) rings.

My testing took place on my private range, which is equipped with silhouettes out to 600-yards. But I began on the 100-yard line in order to properly zero the rifle to shoot dead-on at that range with the index dial turned to the zero stop point. Once I became satisfied at that my bullets were consistently impacting at the center of the target at that range I moved on to 600-yards. The ammo consisted primarily of Hornady Superformance factory-loads in both 120-grain GMX® and 129-grain SST® bullets, but I supplemented a few of my handloads as well. Through the live-fire at 600-yards I found that an adjustment of 5.0 was necessary when shooting the 120-grain GMX rounds and when firing the 129-grain SST ammo a setting of 6.5 MOA seemed to be perfect. Later on I checked to see what those setting looked like at 100-yards and found that the 129-grain SST® bullets impacted 6″ high and the 120-grain GMX® were about 5-1/2″ high.

From the onset, I wondered if the M.O.A.B/M.R.A.B would accurately be able to return to an earlier setting without experiencing a change in the impact point. So, once I’d established a relationship between the M.O.A.B/M.R.A.B index dial settings and where the bullets were falling on the target at 100-yards I repeated switched the setting back and forth, each time looking for any noticeable deviation that might start to materialize. I used the 100-yard range for this purpose because I thought it would eliminate some of the human error that could result in skewing the data. Heaven knows that I have plenty of that to go around. Eventually, however, I moved back to the 600-yard range. The result was a pleasing one. Unlike what sometimes occurs when a reticle is moved around, the M.O.A.B/M.R.A.B system seemed to have a very accurate memory when it came to returning the bullets to the previous set point of impact.

It should be pointed out that the M.O.A.B/M.R.A.B system has a tendency to add a bit of height to the scope positioning. In the case of the Model 150 MOA it essentially amounted about an inch and an additional 1/4-inch can be expected with the Model 300 MOA. You can keep the scope height to a minimum by of course using low rings, but still this increase could in some cases be viewed as a negative. If your rifle isn’t equipped with a comb adjustable style stock it might be advisable to look into some form of aftermarket stock comb height extender. These are usually made of leather or canvas and can be easily added to the buttstock of your rifle in order to allow for better eye-to-scope alignment. In most cases these come in form of strap-on, peel-and-stick, or lace-up designs that can be easily and quickly removed when not needed. A few of the companies selling those products are: Brauer Bros., Kick-Eez, D&E, Smith Enterprise and others, many of which can be found at Brownell’s.

— Jim Mullin

I feel compelled to talk a little to the novice shooter on the issue of trajectory. While the following may seem rudimentary to the experience long-range shooters – it might be helpful to those that are a bit less experienced in this area. Most shooters naturally are drawn to the use of trajectory tables, charts, ballistic computer programs or even the box that your cartridge came in for data on the trajectory at extended range, but no one should look at these as being perfect by any stretch of the imagination. First off, there are many factors that can affect, in some cases dramatically affect, the trajectory of the bullet. And second, and possibly even more important is the fact that in some cases these tables can be quite easily misinterpreted. One of the potential areas of confusion comes into play when the ballistic chart displays the data in the seemingly backward fashion of how much the bullet is expected to drop at various ranges when the scope is adjusted for a dead-on impact at 100-yards.

A much better format would be to present the data as how high the bullet would be impacting at 100-yards when the scope was set for a dead-on hit at the extended range you are planning to shoot. For example purposes let’s say that with a dead-on impact at 100-yards the bullet is suppose to drop by 40-inches at the 500-yards. That is probably a fairly common amount of drop for a relatively flat shooting cartridge. In this case a novice to long-range shooting could misinterpret that data as meaning that they should adjust their Cold Shot M.O.A.B. the equivalent of 40 MOA (160 clicks) in order for the bullet to properly impact at 500-yards. In reality, however, the adjustment needed would be considerably less than that amount.

In my own case, shooting the Savage Arms chambered for 6.5 Creedmore, I found that I needed to adjust the M.O.A.B. in one case as little as 5 MOA to achieve a proper impact at 600-yards. The basic reason why only that amount of adjustment was necessary is based on the fact that when I began elevating the rear of the M.O.A.B., in turn raising the muzzle of the rifle, it resulted in dramatically changing the flight pattern of the bullet. Okay, that is pretty understandable, but things get a little more complicated when you attempt to determine exactly how much adjustment will be necessary to get your bullets to impact where you want them. Most shooters will still begin with one of the earlier methods to get them in the ballpark, but there is no substitute for actual live-fire shooting to determine exactly where you bullets will be impacting.

— Jim Mullin

I can remember as a kid playing with my toys over and over again with my dad eventually reminding me that they would only last so long. I thought at the time he was simply getting tired of the noise that I was making with them, but now I think he was trying to teach me about planned obsolesce. Usually I would ignore his warnings, followed by his prediction eventually coming true in the form of the toy wearing out and breaking. Like my toys, the internal working of your scope may eventually wear out. Scope manufacturers design their products, like virtually all other types of manufacturers, on a duty cycle basis. In other words, they are engineered to function a certain number of times. After that the internal workings of your scope may go south on you. The way to avoid that happening may be as simple as limiting the number of times you adjust the reticles. And if you are one of those long-range shooters that sometimes work on the edge of the envelope with a limited amount of adjustment and are tempted to squeeze one more minute of angle out of your scope – well, you should expect that duty cycle to become shortened even more. That is where the Cold Shot M.O.A.B/M.R.A.B system may be a better choice. Once your reticle has been set, you can forget about any further adjustment and turn to the index dial of the M.O.A.B/M.R.A.B instead. And, because you have a much larger range of adjustment with the M.O.A.B/M.R.A.B there should never be a need to torque the setting a bit too far.

— Jim Mullin


Cold Shot M.O.A.B./M.R.A.B – No More Reticle Moving

Jim Mullin

Jim Mullin

Many years ago I read a letter in a gun magazine that is today as fresh in my mind as it was when it first read it. You know the kind; a novice gun owner was writing for advice from one of the magazine’s self-professed experts. The writer of the letter was concerned over the fact that his scope reticle wasn’t moving in the precise manner he thought it should. His scope, like many others, was designed to have a 1/4 MOA adjustment. In other words, each click of the turret dial was suppose to move the point of impact by 1/4″ at 100-yards. To his annoyance the shooter found that it was often necessary to jockey his crosshairs back and forth in order to achieve the exact setting he was looking for. Fire a shot – impacted an inch high. Adjust down 1 MOA and fire another shot. Impacted 1-inches low, and it went on from there. As is frequently the case, the magazine published both the shooter’s letter and the “expert’s” advice, which went something like this. The owner of the scope was told that his scope was in severe need of being repaired and that he should immediately ship it back to the factory in order for it to be gone through and the problem fixed. Oh by the way, the magazine was not The Varmint Hunter!

The reason why that particular letter has stayed with me all those years is because of the seemingly faulty advice that was given. Certainly there could have been something wrong with the internal workings of the scope, but I’m betting it was nothing that a repair shop would, or could correct, because I have frequently found myself facing that same problem. And no, this isn’t a trait akin only to low-cost, bargain-basket scopes that were built and assembled in some obscure Asian rim sweatshop by workers paid pennies on the hour. On the contrary, in many of my own cases I had to swallow hard when it came laying my credit card down on the sales counter to purchase some of those very same scopes. While I can’t tell you why this problem occurs, I can tell you that it is a more common phenomenon than the scope manufacturers would like you to believe.

Clearly, this situation can become a bit trying for anyone attempting to initially zero their riflescope, but for those shooters that prefer to simply “dial-in” their shots for long-range shooting it can become a major issue to content with. Think about it – a couple of inches at 100-yards translates into a foot at 600-yards. The good news is that there is a brand new and much more reliable alternative to frequently moving the reticle of your scope around. It is called the “Minute of Angle Base/Mil Radian Adjustment Base”, or “M.O.A.B./M.R.A.B” for short. When installed on your rifle the M.O.A.B./M.R.A.B allows the shooter to compensate for the trajectory drop of their bullets in a mechanical way rather than optically. In other words, rather than moving the reticle up and down to adjust your scope variations in range you can achieve the same result by elevating or lowering the rearmost portion of the M.O.A.B/M.R.A.B. By doing so it eliminates unnecessary wear inside the scope; it provides you with a greater range of adjustability; and in my way of thinking it is a more reliable and dependable way to adjust your point of impact without ever having to deal with the delicate internal workings inside the scope.

The basic concept of adjusting the point of bullet impact through the use of the mounting base is not a new one. It has its roots within the first production riflescope built in 1855 by William Malcolm. Malcolm was the first to offer an adjustable ocular lens and he did so using his own adjustable mounting system that moved the entire scope tube vertically or horizontally in order to align it with the target. Jim Mullin of Cold Shot LLC of course went much further in his development of the M.O.A.B/M.R.A.B system than Malcolm did over a century and a half ago. Unlike Malcolm’s somewhat crude and rudimentary attempt, Mullin’s system comes with the CNC precision necessary to achieve the highest degree of accuracy at ranges never conceived in Malcolm’s days.

The M.O.A.B/M.R.A.B system is used in conjunction with a normal full length MIL-SPEC M1913 Picatinny rail. When in place it allows the shooter to dial-in their scope by simply turning an index dial located at rearmost portion of the M.O.A.B./M.R.A.B. I hesitate to make such a rude comparison, but the index wheel of the M.O.A.B/M.R.A.B. actually appears similar to a scaled down version of the old time label-marker dial. You know the kind; where a turn of the wheel allows you to select the letter you are looking for. Obviously, there was never a label-maker ever built that came with the precision, close tolerances and quality of construction that are inherent in the M.O.A.B/M.R.A.B There are 5 models of M.O.A.B/M.R.A.B to select from: 150 MOA, 300 MOA, 72 MIL, 144 MIL and a specific unit intended for M-1A/M-14 rifles. In most shooting situations I believe the Model 150 MOA or 72 MIL is likely the best choice and provides an adequate amount of adjustment for most rifles and shooting scenarios. The 300 MOA,144 MIL  is possibly best suited for applications like the Barrett M-87A1 and other Extreme long range large bore weapons.

— Jim Mullin