Optic of the week: Leupold MK4 3.5-10X40


Long ago when I used to read about firearms, when the term “sniper scope” was said, is was probably referring to the Leupold MK4 series.

I was going to write some history, but instead I am going to quote, Dyspeptic Gunsmith who summed it up nicely.

40+ years ago, many consumer-grade were notoriously unreliable.

Oh, they’d claim to be water-sealed, but you’d dunk them in the bathroom sink and see a steady stream of bubbles come out of them. You’d put them on a heavier-recoiling magnum and you could see the zero walk all over the place – I even had a scope in the early 80’s, which, when mounted on a “mountain rifle light” ’06, had the reticle obviously come loose inside the scope.

There were all manner of issues with the less expensive scopes 40+ years ago.

Leupold commanded a premium because of their no-BS warranty – and quality. Being able to send a Leupold back to the factory and they’d fix it – for nothing other than the shipping cost to send it to them – was a huge reason why so many people who could afford the price chose Leupold as their scope of choice (modulo the specialized scopes like the Unertls). The European scopes were ferociously priced out of the range of most shooters in the US, and they were both rare in the market and difficult to support.

I remember reading one guide saying to buy WWII surplus scopes because they were build better than anything available on the commercial market.  I doubt anyone sane would agree with that statement now.  The glass coatings on the cheapest of Chinese scopes now outclass anything available then.

But back to the topic at hand.

Leupold offers a massive variety of scopes and variations of their scopes.  Different reticles, turret options, finishes, etc.  I don’t know if anyone offers any where near as many different options as Leupold does.  This also means many different versions of the same scope.

Cheaper 3-9x were often seen on hunting rifles, the higher end MK14 3.5-10x was seen commonly on competition and police sniper Remington 700s.  An illuminated version of this scope was used on the M110 sniper rifle.

Rule of thumb back then was that you wanted the 1x time the distance in hundreds of yards for the amount of magnification you would use.  So it was figured a 10x scope was what you needed for 1000 yards.  I recall seeing the Leopold 3.5-10x, 4.5-14x, and the 6.5-20x as the most common scopes among “serious” shooters for a long time.  Slowly other brands took over that market share, Nightforce being one of the major ones.  You could get the scope with a fine duplex reticle and target turrets or coarse adjustments with a mildot.

For example, on this particular scope the elevation are 1 MOA clicks and 1/2 MOA windage clicks.  The idea behind the coarse elevation clicks is to allow a sniper to very quickly adjust for distance.  Elevation knobs are also marked for bullet drop.  This one is marked 168 grain .308.  You can have Leupold make you a custom marked turret.  Some of these scopes that were used by the military have a BDC cap for M118LR out of a 20 inch barrel.

I’m going to omit going into the specs and stats of this scope as it is no longer in production to sell to the public.  Due to continued demand from law enforcement and military, Leupold will make these if they special order them.  Apparently Leupold would prefer if you switched to one of their newer and improved designs, but enough agencies out there want these classics.

This can be a good deal for you.  If you keep your eyes out you may find used Leupolds for sale by people have to have upgraded to newer scopes.  These older scopes have plenty of life left in them.


  1. One of these jewels was my first “real” scope when they first hit the streets almost 20yrs ago now. They were still under their Vari-X III LR line then. I got mine through Premier Reticles with one of their “football” mildot conversions. They put luminescent film on the thick outer posts when illuminated reticles still hadn’t fully caught on. Neat stuff and still have it. In fact, have a couple more though the later M2 dial version is probably the best of all varieties of this optic in my humble opinion. The 1/2 MOA elevation and windage adjustments on the M2 dials are more than adequate for superb accuracy and keeping the quick math-in-public calculations easier.

    Note that the older version’s elevation dial spun the opposite direction compared to later models if anyone has plans for a different or custom dial.


Please enter your comment!
Please enter your name here