Effective and Maximum Range for 6mm BB's Section IV: Effective and Maximum Range for 6mm BB's Section IV-A: Definitions of Effective and Maximum Range I consider the effective range of an airsoft rifle to be the range at which the BB deviates significantly from the shooter's line of aim. Take the example of a stock Tokyo Marui rifle firing at 0.75 fps with 0.25g BB's. Without hop-up, the BB's would quickly begin accelerating downward, consequently deviating from the shooter's line of aim. A quick estimate from looking at Figure IV-A-01, without hop-up the same rifle would be effective out to about 40 feet. With hop-up properly adjusted for the rifle and same ammunition, the effective range increases to around 100 feet, at which point the BB is roughly 6 inches below the line of aim. (Note that the line of aim is not necessarily a height of 0', nor is it perpendicular to the ground. The reason for this is parallax, which can be better understood by visiting a website that goes into detail about marksmanship.) A shooter could sight their rifle in at a different range, thereby increasing the effective range.
Airsoft Bb Fps Chart
In Figures IV-A-02, 03, & 04, we can see how this factors in for a sniper rifle firing 0.29g BB's at 415 fps. In Figure IV-A-02, the rifle has been sighted in at 130'. In the case, the effective range (taken as the range at which the BB is 6' below the line of aim) is about 170'. Sighting the rifle to 150' increases the effective range to about 180', as depicted in Figure IV-A-03: Lastly, sighting the rifle to 170' increases the effective range to about 190', as shown in Figure IV-A-04: Keep in mind that given the inherent inaccuracy of airsoft, it is very difficult to sight rifles in at long distances. Additionally, it should be obvious that effective range is not strictly governed by muzzle energy nor the weight of the ammunition used. Further, the skills of the shooter come into play in determining the effective range. The effective ranges listed further down are merely rough estimates.
Airsoft Fps Conversion
No one lives forever 64 bit patch. Maximum range was calculated by determining the firing angle that produced the greatest range. While this of no practical use as lobbed shots are in no way accurate, it will give the shooter an idea of how far their BB might travel. Figure IV-A-05 depicts the maximum range of the same 0.29g BB used in the previous example: At maximum range, the BB is moving very slowly, often at a velocity near its terminal velocity (which is explained in ).
At such ranges, the BB will impact with very little kinetic energy, striking with about the same intensity as a small raindrop. In the above example, at a range of 385 feet the 0.29g BB will be moving at roughly 49 fps (or about 0.03 J), not even enough to dent a sheet of paper. The table below shows shows the firing angle necessary to achieve the maximum range. Note that this is not necessarily 45 degrees. In a vacuum, a firing angle of 45 degrees would provide the greatest range. However, given that the BB falls rapidly during the terminal phase of its trajectory, an angle lower than 45 degrees is necessary to achieve maximum range. Figure IV-A-06 shows how trajectories vary by firing angle for a 0.20g BB fired at 0.75 J.
Section IV-B: Effective Range and Recommended BB Weight Weight is the recommended BB weight necessary to achieve the listed effective range. Modified Muzzle Velocity is the muzzle velocity achieved with the recommended weight BB at the given muzzle energy. Effective Range is the range at which the theoretical BB fired from a properly tuned rifle will experience significant deviation from the average trajectory, with a maximum deviation of 6' (explained above). These numbers are not absolute; marksman skills (or lack thereof) will either diminish or extend the range. Further, rifles with exceptional consistency between shots can achieve greater effective ranges, as can a shooter by accounting for holdover. Maximum Range is the maximum possible range achievable when using the recommended weight.
Keep in mind that a tailwind or higher altitudes / temperatures will allow for a longer ranges. Maximum Angle is the firing angle that would achieve the maximum range with the listed weight. MED is the minimum engagement distance for the given velocity and BB weight, allowing for a maximum impact energy of 1.00 J.
FPS stands for Feet Per Second, for those of you who hate anything other than SI units (Systeme Internationale), one fps is 0.304 meters/sec, (equivalently 1m/s = 3.28 fps). This is why 328fps is thrown around as a limit. 328fps is 100m/s, and a 0.2g bb travelling at this speed possess the energy of exactly 1 Joule. Energy (in joules) = 1/2 mass. velovity^2 How can I calculate my airsoft replica's energy?
Using this handy form you can calculate your replica's energy in joules. As a by-product it'll also give you your bb's velocity in m/s. To calculate the energy in joules, simply enter the mass of ammunition (in grams) that you use, and the fps that you've read from your chrono unit. Input Values: BB weight (in grams). You can also enter another number in the Energy(Joule) box, and click 'Convert' to get that figure in Foot-Pounds.
So how does extra FPS affect my range? Well I've been having a think about this, and we will be conducting some tests with some AEG's at some point in the warmer part of the summer, from these we'll be able to deduce some real-world figures.
Right now though the easiest thing that I can do is calculate some range using basic physics, making certain assumptions. For starters we'll ignore hop-up, as we know it increases range, and I'm not going to sit here and work out higher level physics using specific air density and fluid dynamics - I'll do that later on =). This model assumes a curved flight path, I know hop-up produces a straighter path, but you'll be suprised how close the figures from this model match to real-life. From basic physics, lets start with a basic equation: s = distance u = initial velocity v = final velocity a = acceleration t = time passed s = ut + 1/2 at^2 Assume you are firing the bb from a height of 1metre (i.e. With your rifle shouldered), lets calculate the time it takes for your bb to drop and hit the ground: s = ut + 1/2 at^2 hence, 1 = 0 + (0.5. Free download mcafee sdat.exe.
9.81). t^2 t = sqrt( 1/(0.5.9.81) ) t = sqrt(0.203.) t = 0.45 seconds (2SF) Hence time taken to fall 1 metre is 0.45 seconds. With a velocity of 328fps or 100m/s, this mean your bb will travel (328.0.45)= 148feet or 45metres before hitting the ground, giving you your effective range.
If you don't know the energy of your rifle, you can either calculate it above, or use 1J as the limit for AEG's, and 2.31J as the limit for single action. You can use this small javascript form to calculate your theoretical effective range.
Please note this ignores a lot of physical factors, and assumes a firing height of 1 metre off the ground, and assumes that you are firing over a level 'range'. Initial values Mass (grammes) Energy (Joule) Results: (all to 2 SF) Muzzle velocity (fps) (m/s) Effective range (feet) (m).
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