Making do with gear is much different than using gear made for. While it may seem trivial, for mission critical equipment I can assure you it is not.
Define the mission
When selecting gear, the most important consideration is defining the mission. In this case, what is the intended purpose of your rifle. We define them either as a general purpose (GP) rifle or a designated marksman (DM) rifle. Your DM rifles have a specific purpose and as such must have accessories to support the mission. These rifles make up a small percentage of rifles out in the world. The more popular rifles are the GP and rightfully so, they support a wider set of mission parameters.
Sight Systems
As a GP rifle the subject of sight systems comes up in classes frequently and we try to answer by providing our selection criterion. Your options are iron sights, red dot optics or magnified optics. For the GP rifles you can exclude iron sights as your primary, they are regulated to backups and magnified optics are not the end all be all. The selection criterion is weight/size, durability, accuracy, view ability and battery life. I’ve had these criterion in place for over a decade and surprised to see some manufactures not getting it or moving off in their own direction. As a point of reference we want our GP rifle optimized for peak performance out to 300m. Some may criticize my view on magnified optics for a GP rifle, but honestly engaging targets at more than 100m is possible though not probable.
Optimized performance
This is why you must define your mission, if the majority of your engagement range scenarios are less than 100m the extra weight, size and eye relief at close range is suboptimal compared to the modern RDS. A common justification for magnified optics is positive target identification and I’m totally down with that, but before you can identify you have to locate and reduced field of view from magnification may not be the best tool for the task. On a GP rifle some magnification is good, but balancing weight/size with speed and viewability make it far less appealing. While shooting prone helps to mitigate the concerns of weight/size it’s hard to achieve in an urban setting; which leaves kneeling and standing. You’ll feel the extra weight/size there and not in a positive way.
Micro Baggage
When we look at RDS the first thing we look for is weight/size. I want the smallest and lightest while still giving me view ability, accuracy and battery life. The gold standard for weight/size is the Aimpoint Micro T2 coming in at a mere 3.4 ounces. The durability of these little suckers is pretty impressive and even being run over or burned in a fire they still perform. I haven’t seen or heard similar anecdotes from other competitors and while that’s not to say it can’t or hasn’t happened it has for the Aimpoint line and that speaks volumes. Accuracy is broken down into the size of the reticule/dot and the corrective value. If you’re going to put this on a rifle you need both those to balance out. What do I mean by that? If you have a 1MOA dot, but 1MOA corrective value that’s not going to be as inheritely accurate as a 2MOA dot with ½MOA corrective value. First, the eye will have a hard time discerning the difference between 1MOA & 2MOA, especially under pressure. Then the more precise corrective value will give more precise corrections all things being equal. Of course, the user does have some factoring to add into the mix.
Battery life
The big thing for me is battery life, I like the idea of having to replace the barrel before the battery because I’m getting stupid levels of efficiency from new technology. While I don’t suggest that protocol, it’s nice to know you could if you wanted. Other optics have decent battery life, but I’m looking for a minimum of 30,000 hours as a baseline. At a certain point there could be a little overkill, but as long as the unit is still compact and getting crazy battery life I’m good. Typically I leave my optics on, all the time. Regardless of traveling, storage or usage I keep them powered up and ready to go. My protocol is to change batteries once a year, I could easily go longer, but it becomes a management issue on my end.
The bottom line is you want as light and small a package as you can get with about 30,000 hours of battery life. Then a 2MOA or better reticule and a corrective value of ½MOA to put on your GP rifles.