Leupold Mark 4 Scopes - ER/T vs. LR/T
The Leupold Mark 4 series of riflescopes includes a number of high end tactical scopes; however, the ER/T (Extended Range Tactical) and LR/T (Long Range Tactical), as their names imply, are the models designed for long range shooting. While there are many similarities between the ER/T and LR/T versions there are also some important differences.
These long range Mark 4 scopes, like many tactical scopes, are built on a 30mm main tube which provides more field of view and/or more adjustment range than 1” tubes. However, there is one model, an ER/T 6.5-20x50mm model that is built on a 34mm main tube. Side Note - This scope with the Horus H-58 reticle is the one being issued on the new Army XM2010 .300 Winchester Magnum sniper rifle.
The LR/T and ER/T scopes are both available with a variety of different tactical turrets. Below is a brief description of each turret style and is an important aspect to consider when deciding on which scope model is best for you.
M1 - 1/4 MOA elevation, 1/4 MOA wind - Tall Turrets
M2 - 1/2 MOA elevation, 1/2 MOA wind - Medium or Short Turrets
M3 - 1 MOA elevation, 1/2 MOA wind – Medium Turrets
M5 - .1 Mil elevation, .1 Mil wind – Tall Turrets
Side Focus and Matte Finish
Both ER/T and LR/T modes utilize a side focus parallax correction knob on the left side of the scope when viewed from behind. Parallax adjustment on scopes of these types is a must and the nine o’clock position is generally greatly preferred over the adjustable objective style of parallax correction. Nearly all ER/T and LR/T scopes come with a matte black finish with the LR/T 3.5-10x40mm LR/T with M2 turret in a Dark Earth coloring being the only exception we could find.
ER/T vs LR/T
|ER/T Overview||ER/T 4.5-14x50||LR/T 6.5-20 x 50mm||LR/T Overview|
First Focal Plane Reticles
Horus Reticles Available
Illuminated Models Avail.
Fixed Powered Options
30mm Main Tubes
|ER/T Options||ER/T 8.5-25 x 50mm||LR/T 10 x 40mm||LR/T Options|
One of the biggest differences between the ER/T and LR/T models is where the reticle is placed. All ER/T models have a First Focal Plane reticle meaning that the reticle will stay in proportion to the target no matter what magnification the scope is one. Only some versions of the LR/T 3.5-10x40mm versions are available with a First Focal Plane while the remainder of models in the LR/T line all have their reticle in the Second Focal Plane.
Many of the LR/T scope models are available with partial illumination, meaning that while the entire reticle is not lit; the center part near where the crosshairs intersect is illuminated. No illuminated reticle options are available on the ER/T models.
While some LR/T models are available with illumination, it is the ER/T scopes that feature more reticle choices. More specifically some of the long range Horus reticles are available on several ER/T models. Essentially these reticles provide a grid of holdover points in the lower part of the reticle. These reticles are not available on any of the LR/T scopes.
Magnifications and Objectives
Both the ER/T and LR/T are available in 4.5-14x50, 6.5-20x50 and 8.5-25x50; however the LR/T series is also has 3.5-10x40, and 4.5-14x40mm versions along with two fixed powered options: including two 10x40 models, and one 16x40 model. Note, that all ER/T scope models come with 50mm objectives.
Choosing a Model
With so many options and versions available selecting the one of these scopes can be a bit of a process. We have put together a guide of models, specifications, and model numbers to help you choose the model that best meets your requirements. Below are a few factors to keep in mind when selecting your Mark 4.
1) All ER/T models and some 3.5-10x40 LR/T models feature First Focal Plane Reticles.
2) Illumination is available only on some LR/T models and is not available on ER/T scopes.
3) The TMR (Tactical Milling Reticle) essentially has small hash marks at .5 mils, and large hash marks at 1 mils.
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