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  • SFP vs FFP

    With the United States engaged in the Global War on Terror for over a decade, there has been an increased demand for front focal plane optics by Law Enforcement. This growing trend is a direct result of lessons learned by our military and the frequent collaboration with Law Enforcement in training events and conferences. Since the question of which optical platform is best for Law Enforcement use is a frequent one, we’d like to provide you with some information that will help you make the right choice for your application. The intent of this document is to educate you on the differences, as well as the pros and cons of both for use in the Law Enforcement role.
    Let’s begin with proper explanations of each.

    First Focal Plane Reticle: A First Focal Plane reticle gets its name due to the position of its placement in the erector tube assembly; in the front portion directly adjacent to the adjustment turret mechanism, which is why it is also referred to as a Front Focal Plane reticle. It is in front of the magnification element of the riflescope; hence the reticle gets magnified throughout the magnification range.

    Due to the location of the reticle in the erector tube, the reticle is able to remain in proportion to the target as the magnification is increased or decreased. This means that visually, the reticle will decrease in size as the magnification is decreased, and increase in size with the target as the magnification is increased. Due to this capability, the reticle’s subtensions remain true on all magnification settings.

    Second Focal Plane Reticle: A Second Focal Plane reticle gets its name due to the position of its placement in the erector tube assembly; in the rear portion near the power zoom ring that is used to adjust the magnification of the riflescope. This is why it is also referred to as a Rear Focal Plane reticle. It is behind the magnification element of the riflescope; hence the reticle does not get magnified throughout the magnification range.

    Due to the location of the reticle in the erector tube, the reticle will remain constant in proportion to the target as the magnification is increased or decreased. This means that visually, the reticle will remain the same size, but the target will appear to get larger or smaller when the magnification is increased or decreased. Due to this, the subtensions of the reticle can only be true at one magnification setting.

    The one aspect that both riflescopes have in common is that they magnify the image of the target, and allow you to adjust Point of Impact (POI) to your Point of Aim (POA). The differences are in how the reticle works. How the reticle works can affect operational integration.

    While both Law Enforcement and the Military work in dynamic environments, one tends to work in a fairly permissive environment where the aggressor is clearly defined in a relatively short target engagement area. The other usually works in an environment that is non-permissive; the aggressors aren’t clearly defined at all and the target engagement area is as far as line-of-sight will allow.

    Due to most Americans being law abiding citizens with a generally positive view of Law Enforcement, the Law Enforcement Sniper almost universally operates in a permissive environment and the aggressor(s) is clearly defined. More often than not, the LE Sniper is reactionary to a specific location – often a building or a house with barricaded suspects. Their primary role is to observe and provide intelligence to the Incident Command Center as negotiations take place or an entry team assembles. The static positions often mean dealing with a target or targets at a known distance at ranges that are usually inside of 100yds.

    The military sniper on the other hand, is almost always located in non-permissive environments where the aggressors may or may not be clearly defined. If not on active patrols, they are usually in overwatch positions to engage a target or multiple targets of opportunity. Sometimes the distances are known, sometimes they are not. More often than not, the Military Sniper is dealing with multiple threat targets at varying distances from 0 meters or yards to in excess of 1000 meters or yards. By the very nature of operating in such a vast potential engagement window and dealing with multiple targets at varying distances, it tends to be a more dynamic and changing environment than the Law Enforcement environment.

    Typically the best hide for the LE Sniper tends to be somewhere rather close to the structure/threat due to the environment. The closer distances allow them to be more precise in their shots and keep innocent people between the suspect and sniper to an absolute minimum. These distances are often within 100yds, but can be 50yds or less. Granted, while a Sniper in a more rural setting will have different options, the distances still tend to be closer for the same reasons the urban sniper deals with.

    In situations that mandate that you are so close to your threat, it is often imperative to turn the magnification down to a setting that gives you maximum field of view in order to observe without panning or scanning. If you were to turn the magnification down to the minimum setting on a FFP scope, then the reticle becomes very thin and difficult to see. If/when a threat were to present itself and a quick shot were required, it very well may be necessary to have to turn the magnification up to a point where the reticle is visible against the target. An illuminated reticle can sometimes help alleviate this problem but most reticles are not daytime visible. This would only become a benefit if the situation were occurring in a limited to no light situation, and having your reticle illuminated without a Killflash or Anti Reflection Device(ARD) can possibly give away your position as it can be viewed by a skilled forward observer. A lot of things affect how well you can see your reticle; shadows, varying light, target color, target background, viewing through glass, differing vegetation, sun position, reflections, etc. all have an impact on how you see your reticle against your target. This is where the SFP reticle riflescopes become a benefit to the LE Sniper. The reticle remains constant in size throughout the magnification range. The shot usually requires a POA/POI hold or something so close that it can be judged by a feature hold on the target. The subtensions on the reticle may not be correct, but given the distances of the engagement and the nature of the environment, it becomes a non-issue and can be satisfied by dialing your proper zero for your given range if needed. Ranging with your reticle, windage holds for wind and moving targets are also rather limited in the LE Role to where they are very common in the Military Role.

    One common theme between the two professions is the use of forward mounted Night Vision Devices (NVD’s) like the UNS and MUNS. The use of NVD’s can limit the use of the optic on maximum magnification. Most clip-on NVD’s are optimized for use in the 6 - 10x magnification range. This could be said that it is a benefit to utilize a front focal plane scope and I will agree, but with proper knowledge of how a second focal plane scope reticle subtends at different magnifications, it becomes a non-issue. It is also not an issue if utilization of the subtended holds aren’t necessary.

    In conclusion, the second focal plane riflescope still very much has its place for the Law Enforcement role while the opposite is found to be true for the Military Role. It is imperative when your agency is selecting the equipment needed for its mission, that it select the equipment that will benefit the team in accomplishing their mission – and not hinder it. When selecting your optics, make sure that you look at all sides of the equation to determine what will work best for you.
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  • #2
    [quote]
    If you were to turn the magnification down to the minimum setting on a FFP scope, then the reticle becomes very thin and difficult to see. If/when a threat were to present itself and a quick shot were required, it very well may be necessary to have to turn the magnification up to a point where the reticle is visible against the target. An illuminated reticle can sometimes help alleviate this problem but most reticles are not daytime visible.[/b]

    Great post. Reticle design can play a huge role in whether or not you can see it at low magnification. Some of them just flat out suck in this regard, while others work pretty well. I think they are getting better as time goes on, enough people are complaining and giving the manufactures input and they are improving them. It gets harder as the magnification ratio goes up. Having a usable reticle on 3x while not be to big at 18x is pretty difficult. My SWFA SS 5-20x seems to work pretty well. I am able to use it well at 5x. If it went down to 3x though, that may present as issue.

    One other benefit of a FFP vs an SFP is a FFP won't have a POI change when changing magnification. Some SFP scopes even more expensive ones can have issue's with this. I am not sure of all the technical details of this, but because the reticle itself is not part of the erector it is harder to design one so that the POI does not change.

    Anyway, again great post.
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