Description
Last update on February 5, 2023 // Source: Amazon API
Rifle Scope Product Details
Thompson Center Arms 9948 3-9×40 3-9x 40mm Obj 36 Ft @ 100 Yds/12 by Thompson Center
Mfg Item Num: 9948 Category: OPTICS – SCOPES Magnification :3-9x Objective :40mm Field of View :36 ft @ 100 yds/12 ft @100 yds Eye Relief :4 in Tube Diameter :1 in Length :12.25 in Weight :13 oz Finish :Black Reticle :Multi-X Adj Size :1/4 MOA @ 100 yds
Rifle Scope Product Features
About the Thompson Center Brand
Thompson Center is a premium supplier for rifle scopes, optics, mounting solutions, and other components used for firearms like rifles and long guns. They style and manufacture their mounts and related products by applying building materials which are resilient and long lasting. This includes the Thompson Center Arms 9948 3-9×40 3-9x 40mm Obj 36 Ft @ 100 Yds/12 by Thompson Center by Thompson Center. For additional shooting items, visit their website.
What You Need to Know About Rifle Scopes
Rifle scopes allow you to specifically align a rifle at different targets by lining up your eye with the target over a range. They do this through zoom by using a series of lenses inside the scope. The scope’s positioning can be dialed in for consideration of various ecological factors like wind and elevation decreases to make up for bullet drop.
The scope’s purpose is to help the shooter understand precisely where the bullet will land based upon the sight picture you are viewing with the optic as you align the scope’s crosshair or reticle with the intended point of impact. A lot of contemporary rifle scopes have around 11 parts which are located within and on the exterior of the scope. These scope parts consist of the rifle scope’s body, lenses, windage and elevation dials or turrets, objective focus rings, and other parts. See all eleven parts of a rifle optical system.
Rifle Optic Varieties
Rifle scopes can be either “first focal plane” or “second focal plane” type of optics. Considering the best type of rifle glass depends on what type of shooting you plan on doing.
Info About First Focal Plane Optics
Focal plane scopes (FFP) feature the reticle in front of the zoom lens. This triggers the reticle to increase in size based on the amount of magnification being used. The benefit is that the reticle measurements are the same at the amplified range as they are at the non amplified distance. One tick on a mil-dot reticle at 100 yards without “zoom” is still the identical tick at 100 yards with 5x “zoom”. These types of scopes are practical for:
- Quick acquisition, far away types of shooting
- Shooting situations where estimations are minor
- Experienced shooters who know their aim point “hold over” and “lead” correlations for their long gun
- Shooters who do not mind the reticle is enlarged and requires more visual eyesight room than a SFP reticle
About Second Focal Plane Optics
Second focal plane optics (SFP) feature the reticle behind the zoom lens. This induces the reticle to stay at the very same scale in relation to the amount of magnification being used. The final result is that the reticle measurements evolve based on the zoom used to shoot over longer ranges due to the fact that the reticle measurements represent distinct increments which fluctuate with the zoom. In the FFP example with the SFP glass, the 5x “zoom” one hundred yard tick reticle measurement would be 1/5th of the non “zoom” tick. These particular varieties of glass work for:
- Long distance styles of shooting where shooters have more time to make ballistic calculations
- Shooting where most of the shots occur within shorter spaces and ranges
- Shooters who prefer a clearer optic sight picture with less area taken up by the larger sized FFP reticle
Zoom for Rifle Scopes
The quantity of magnification a scope supplies is determined by the diameter, density, and curvatures of the lenses inside of the rifle scope. The magnification of the scope is the “power” of the scope.
Info on Fixed Power Lens Scopes
A single power rifle optic or scope uses a magnification number designator like 4×32. This implies the zoom power of the scope is 4x power and the objective lens is 32mm. The magnification of this type of optic can not change considering that it is a fixed power scope.
Adjustable Power Lens Rifle Optics
Variable power rifle scopes use enhanced power. The power modification is achieved by making use of the power ring part of the scope near the rear of the scope by the eye bell.
Power Levels and Range
Here are some suggested scope power settings and the distances where they could be effectively used. High power scopes will not be as useful as lower magnification rifle scope glass considering too much magnification can be a bad thing. The exact same concept goes for extended distances where the shooter needs to have sufficient power to see exactly where to properly aim the rifle at the target.
Details on Rifle Scope Lens Covering
All present day rifle optic lenses are covered. Lens coating can be an important aspect of a shooting platform when looking at high end rifle optics and scope equipment.
About Lens Coatings – HD Versus ED
Some glass suppliers also use “HD” or high-definition glass finishes that take advantage of different processes, polarizations, elements, and chemicals to extract separate color ranges and viewable definition through lenses. This high-def covering is commonly used with greater density lens glass which drops light’s opportunity to refract through the lens glass. Some scope brands use “HD” to refer to “ED” implying extra-low dispersion glass. ED handles how certain colors are represented on the chromatic spectrum and the chromatic aberration or deviance which is similarly called color distortion or fringing. Chromatic aberration is often obvious around items with hard edges and shapes as light hits the object from particular angles.
Glass Lens Single Finishing Versus Multi-Coating
Different scope lenses can even have different finishings applied to them. All lenses usually have at least some kind of treatment or finishing applied to them before they are used in a rifle scope or optic assembly. This is due to the fact that the lens isn’t just a raw piece of glass. It is part of the finely tuned optic. It requires a coating to be applied to it so that the lens will be optimally functional in many types of environments, degrees of light (full light VS shade), and other shooting conditions.
This lens treatment can safeguard the lens from scratches while lowering glare and other less advantageous things experienced in the shooting environment while sighting in with the scope. The quality of a single coated lens depends on the scope maker and how much you paid for it.
Some scope producers likewise make it a point to define if their optic lenses are coated or “multi” covered. This suggests the lens has multiple treatments applied to the surfaces. If a lens gets multiple treatments, it can show that a manufacturer is taking several actions to combat different environmental elements like an anti-glare finishing, a scratch resistant anti-abrasion finishing, followed by a hydrophilic coating. This additionally does not always imply the multi-coated lens will perform better than a single coated lens. Being “much better” depends upon the producer’s lens treatment innovation and the quality of products used in developing the rifle optic.
What to Know About Anti-water Coating
Water on an optic’s lens does not assist with maintaining a clear sight picture through a scope in any way. Lots of top of the line and high-end scope manufacturers will coat their lenses with a hydrophilic or hydrophobic covering. The Steiner Optics Nano-Protection is a fine example of this type of treatment. It deals with the exterior surfaces of the Steiner glass lens so the water particles can not bind to it or create surface tension. The result is that the water beads move off of the scope to maintain a clear, water free sight picture.
Scope Mounting Choices
Installing solutions for scopes can be found in a couple of choices. There are the standard scope rings which are individually mounted to the optic and one-piece scope mounts which cradle the scope. These different kinds of mounts also typically come in quick release versions which use throw levers which allow rifle shooters to rapidly mount and remove the scope.
Optic Mounts with Hex Key Rings
Standard, clamp design mounting scope rings use hex head screws to mount to the flattop design Picatinny scope mount rails on rifles. These types of scope mounts use two different rings to support the optic, and are made from 7075 T6 billet aluminum which is developed for long range accuracy shooting. This type of scope install is perfect for rifles which require a durable, sound mounting solution which will not move no matter how much the scope is moved or abuse the rifle takes.
Quick-Release Cantilever Rifle Scope Rings
These types of quick-release rifle scope mounts can be used to rapidly take off a scope and connect it to a different rifle. Several scopes can even be swapped out if they all use a compatible design mount. These types of mounts are handy for rifle platforms which are carried a lot, to remove the optic from the rifle for protection, or for optics which are used in between several rifles or are situationally focused.
Sealing and Gas Purging for Rifle Scope Tubes
Wetness inside your rifle optic can spoil a day of shooting and your expensive optic by triggering fogging and creating residue inside of the scope’s tube. Most scopes protect against wetness from getting in the optical tube with a system of sealing O-rings which are water resistant. Usually, these optics can be immersed underneath 20 or 30 feet of water before the water pressure can push moisture past the O-rings. This should be plenty of wetness avoidance for standard use rifles for hunting and sporting purposes, unless you intend on taking your rifle on your motorboat and are concerned about the scope still working if it goes over the side and you can still find the rifle.
Rifle Optic Gas Purging
Another part of avoiding the accumulation of wetness inside of the rifle scope tube is filling the tube with a gas like nitrogen. Because this space is already occupied by the gas, the glass is less impacted by temperature level alterations and pressure differences from the outdoor environment which may potentially allow water vapor to leak in around the seals to fill the void which would otherwise be there. These are good qualities of a decent rifle scope to seek out.
