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You are here: Home / Rifle Scopes / SIGHTRON 25173 SIII Long Range Zero Stop Riflescope, 8-32x56mm, 30mm Tube, MOA Type Reticle, Side Focus, 1/4 Tactical Knobs, Matte
SIGHTRON Rifle Scope 1 SIGHTRON 25173 SIII Long Range Zero Stop Riflescope, 8-32x56mm, 30mm Tube, MOA Type Reticle, Side Focus, 1/4 Tactical Knobs, Matte

SIGHTRON 25173 SIII Long Range Zero Stop Riflescope, 8-32x56mm, 30mm Tube, MOA Type Reticle, Side Focus, 1/4 Tactical Knobs, Matte

Was $918.00 - check current price

Check Out SIGHTRON 25173 SIII Long Range Zero Stop Riflescope, 8-32x56mm, 30mm Tube, MOA Type Reticle, Side Focus, 1/4 Tactical Knobs, Matte. See Great Rifle Scopes By SIGHTRON.

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SKU: 9d485c7c42fa Category: Rifle Scopes Tag: rifle scope
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Description

Rifle Scope Product Details

SIGHTRON 25173 SIII Long Range Zero Stop Riflescope, 8-32x56mm, 30mm Tube, MOA Type Reticle, Side Focus, 1/4 Tactical Knobs, Matte
Sightron SIII long range zero stop riflescope, 8-32x56mm specifications: – magnification: 8-32x – objective diameter: 56mm – main tube diameter: 30mm – reticle: MOA type – side focus – 1/4 tactical knobs – coating: multi coated – finish: matte black.

Rifle Scope Product Features

Magnification: 8-32x
Objective diameter: 56Mm
Main tube diameter: 30Mm

About the SIGHTRON Scope Maker

SIGHTRON is a premium supplier for long gun scopes, optics, mounting solutions, and other components used for firearms like rifles and long guns. They style and build their mounts, scopes, and related products by applying materials which are long lasting and durable. This includes the SIGHTRON 25173 SIII Long Range Zero Stop Riflescope, 8-32x56mm, 30mm Tube, MOA Type Reticle, Side Focus, 1/4 Tactical Knobs, Matte by SIGHTRON. For additional shooting products, visit their site.

Info About Optics

Rifle scopes allow you to precisely aim a rifle at different targets by aligning your eye with the target at range. They do this through zoom by utilizing a set of lenses within the scope. The scope’s alignment can be dialed in for the consideration of various environmental considerations like wind and elevation decreases to make up for bullet drop.

The scope’s function is to understand precisely where the bullet will hit based on the sight picture you are seeing with the scope as you align the scope’s crosshair or reticle with the intended point of impact. The majority of modern-day rifle optics have about eleven parts which are located internally and externally on the scope body. These parts include the rifle scope’s body, lenses, modification turrets or dials, focus rings, and other parts. See all eleven parts of optics.

Rifle Scope Styles

Rifle scopes can be either “first focal plane” or “second focal plane” type of optics. Choosing the finest type of rifle glass is based on what type of shooting you plan to do.

Info About First Focal Plane Glass

Focal plane scopes (FFP) come with the reticle in front of the magnifying lens. This induces the reticle to increase in size based on the extent of zoom being used. The benefit is that the reticle measurements are the same at the amplified range as they are at the non magnified distance. As an example, one tick on a mil-dot reticle at 100 yards without “zoom” is still the same tick at 100 yards with 5x “zoom”. These kinds of scopes work for:

  • Quick acquisition, long distance types of shooting
  • Shooting circumstances where calculations are marginal
  • Experienced shooters who know their aim point “hold over” and “lead” equations for their firearm
  • Shooters who don’t mind the reticle is bigger and requires more visual sight room than a SFP reticle

Info About Second Focal Plane Optics

Second focal plane scopes (SFP) come with the reticle to the rear of the magnification lens. This causes the reticle to remain at the very same scale in relation to the level of zoom being used. The end result is that the reticle measurements alter based on the magnification employed to shoot over lengthier ranges considering the reticle markings represent different increments which fluctuate with the zoom. In the FFP illustration with the SFP glass, the 5x “zoom” 100 yard tick measurement would be 1/5th of the non “zoom” tick measurement. These particular kinds of optics are useful for:

  • Long distance types of shooting where shooters have increased time to make ballistic estimations
  • Shooting where most of the shots happen within much shorter proximities and ranges
  • Shooters who want a clearer optic sight picture with less area taken up by the larger sized FFP reticle

Rifle Optic Zoom

The extent of scope magnification you need on your optic is based on the style of shooting you intend to do. Pretty much every type of rifle glass supplies some degree of magnification. The quantity of zoom a scope provides is determined by the diameter, density, and curves of the lenses within the rifle optic. The magnification level of the optic is the “power” of the glass. This indicates what the shooter is aiming at through the scope is magnified times the power factor of what can typically be seen by human eyes.

Single Power Lens Glass Info

A single power rifle optic and scope will have a magnification number designator like 4×32. This indicates the magnification power of the scope is 4x power and the objective lens is 32mm. The magnification of this kind of scope can not change because it is a fixed power optic.

Variable Power Lens Optics

Variable power rifle scopes can be changed between magnification levels. It will note the zoom degree in a configuration such as 2-10×32. These numbers mean the magnification of the scope can be adjusted in between 2x and 10x power. This additionally incorporates the powers in-between 2 and 10. The power adjustment is achieved by employing the power ring part of the scope near the back of the scope by the eye bell piece.

Power and Range

Here are some suggested scope power settings and the ranges where they could be efficiently used. High power rifle scope glass will not be as efficient as lower powered rifle scope glass since too much magnification can be a negative aspect depending on your shooting distance. The same applies to longer ranges where the shooter needs to have enough power to see exactly where to best aim the rifle.

About Optic Lens Finish

All modern-day rifle scope lenses are layered. Lens finishing can be a significant element of a rifle system when considering high end rifle optics and scope systems.

HD Versus ED Glass Lens Coatings

Some scope manufacturers likewise use “HD” or high-definition lens finishes which use different techniques, aspects, chemicals, and polarizations to draw out different colors and viewable quality through the lens. Some scope makers use “HD” to refer to “ED” implying extra-low dispersion glass.

Single Coating Versus Multi-Coating for Rifle Scopes

Various optic lenses can also have various coatings used to them. All lenses generally have at least some type of treatment or coating used to them before they are used in a rifle scope or optic.

Single layered lenses have a treatment applied to them which is usually a protective and enhancing multi-purpose treatment. This lens treatment can preserve the lens from scratches while decreasing glare and other less helpful things experienced in the shooting environment while sighting in with the scope. The quality of a single layered lens depends on the scope developer and how much money you spent on it. Both the manufacturer and amount are indications of the lens quality.

Some scope producers likewise make it a point to define if their optic lenses are layered or “multi” coated. This suggests the lens has multiple treatments applied to the surfaces of the glass. If a lens gets multiple treatments, it can indicate that a manufacturer is taking multiple actions to fight various environmental elements like an anti-glare finish, a scratch resistant anti-abrasion coating, followed by a hydrophilic covering. This also does not necessarily suggest the multi-coated lens is better than a single coated lens. Being “much better” is dependent on the producer’s lens treatment innovation and the quality of glass used in building the rifle optic.

Hydrophobic Scope Lens Covering

Water on a lens doesn’t assist with maintaining a clear sight picture through a scope at all. Many top of the line and military grade scope companies will coat their lenses with a hydrophilic or hydrophobic anti-water covering.

Options for Installing Rifle Optics on Long Guns

Installing approaches for scopes can be found in a couple of options. There are the standard scope rings which are individually mounted to the scope and one-piece mounts which cradle the scope. These various types of mounts also normally come in quick release versions which use toss levers which allow rifle operators to rapidly install and remove the glass.

Hex Key Rifle Glass Rings

Basic, clamp type mounting optic rings use hex head screws to fix to the flattop design Picatinny scope mounting rails on the tops of rifles. These kinds of scope mounts use two detached rings to support the scope, and are usually constructed from 7075 T6 billet aluminum or similar materials which are designed for far away accuracy shooting. This type of scope mount is effective for rifle systems which need to have a resilient, unfailing mount which will not shift no matter how much the scope is moved about or jarring the rifle takes. These are the design of mounts you want for a dedicated scope setup on a long distance hunting or competition firearm that will rarely need to be altered or adjusted. Blue 242 Loctite threadlocker can also be used on the scope mount screws to prevent the hex screws from backing out after they are mounted tightly in position. An example of these mounting rings are the 30mm style from the Vortex Optics brand. The set normally costs around $200 USD

Quick-Release Cantilever Optic Ring Mounts

These types of quick-release rifle scope mounts can be used to quickly attach and detach a scope from a rifle. If they all use a comparable style mount, several scopes can often be switched out on the range. The quick detach design is CNC crafted from anodized 6061 T6 aluminum and the mounting levers connect solidly to a flat top type Picatinny rail. This enables the scope to be sighted in while on the rifle, taken off of the rifle, and remounted back on the rifle while preserving precision. These types of mounts come in handy for shooting platforms which are hauled around a lot, to take off the scope from the rifle for protection, or for sight systems which are used in between multiple rifles. An example of this mount style is the 30mm mount designed by Vortex Optics. It generally costs around $250 USD

Sealing and Gas Purging for Glass Tubes

Wetness inside your rifle scope can mess up a day on the range and your expensive optic by resulting in fogging and generating residue inside of the scope tube. Most optics prevent humidity from going into the scope tube with a system of sealing O-rings which are waterproof. Normally, these scopes can be submerged beneath 20 or 30 feet of water before the water pressure can push moisture past the O-rings. This should be sufficient humidity prevention for conventional use rifles, unless you intend on taking your rifle on a boat and are concerned about the optic still functioning if it falls overboard and you can still find the gun.

Scope Gas Purging

Another element of avoiding the accumulation of wetness within the rifle scope tube is filling the tube with a gas like nitrogen. Since this area is already taken up by the gas, the glass is less affected by climate changes and pressure differences from the outdoor environment which might possibly permit water vapor to seep in around the seals to fill the void which would otherwise be there. These are good qualities of a good rifle scope to look for.

Additional information

Category

Rifle Scopes

Brand

SIGHTRON

ASIN

B07DSM2QKV

Reviews

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Prime

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Last update on August 19, 2026 // Source: Amazon API

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