M4 25M Zero Target For Iron Sights

[NousDefionsDoc]

Anybody got one in pdf or something similar?

[Team Sergeant]

http://www.thetacticalsolution.com/docs/25meter_M16A2_zero_target.pdf

:lifter

[NousDefionsDoc]

Many thanks.

[jatx]

Gentlemen, do you know of a technique for using this target to zero or confirm zero for an M4 using a CCO or Eotech?

Many thanks.

[82ndtrooper]

Gentlemen, do you know of a technique for using this target to zero or confirm zero for an M4 using a CCO or Eotech?

Many thanks.

Same question I had. I use the Aimpont Compm2 2MOA. It's parallax free so it's never been a true zero, but under 25 meters I'm only trying to hit what I can see when plinking.

Thanks for the link Team Sergeant. I need this for my new builds.

[Team Sergeant]

Gentlemen, do you know of a technique for using this target to zero or confirm zero for an M4 using a CCO or Eotech?

Many thanks.

EOTEC, IMO is for work 200 to zero meters. A weapons zero depends on your "working" preference.

Tell me what's the bullet drop from zero to 100 meters?

100 to 200?
200 to 300?

It also depends on what model weapon and what you're feeding it.

[jatx]

EOTEC, IMO is for work 200 to zero meters. A weapons zero depends on your "working" preference.

Tell me what's the bullet drop from zero to 100 meters?

100 to 200?
200 to 300?

It also depends on what model weapon and what you're feeding it.

I am using M855 or its moral equivalent, which clocks about 2860 fps out of a 14.5" barrel. Using the JBM online calculator and a 300 yard zero, I estimate bullet drop as:

0-100 4.3 inches
100-200 4.3 + 1.7 inches = 6.0 inches
200-300 0 inches

A 200 yard zero would yield the following:

0-100 1.3 inches
100-200 0 inches

Others may get different results, but I am compensating for the POF Predator rail placing my reticle about 3 inches above bore axis.

While I understand your point about the Eotech, I've had no problem getting good hits with mine out past 300. The way I look at it, the center dot (1.5 MOA) is smaller in diameter than my FSP, so it obstructs less of the target at 300 yards than the iron sights on which I originally qualified.

If I were to use this target for a 300 yard zero and the rifle mentioned above, my inclination would be to hold a dot low from center mass. Since the Eotech's center dot is roughly 4.5 inches in diameter at 300 yards, that means my POI would be within 1 MOA of my POA at all distances <300 yards.

Am I thinking about this right?

[Ambush Master]

I have shot head sized balloons well past the 200-300 meter range , using an Eotec. They appeared to be about the same size, if not smaller than the period at the end of this sentence. These were far enough out that if you took your eye off of it you would have trouble re-acquiring it!! (I HAVE WITNESSES, I did it more than once, and the witness is not Air.177!!!:D )

Later
Martin

[Team Sergeant]

0-100 4.3 inches
100-200 4.3 + 1.7 inches = 6.0 inches
200-300 0 inches

A 200 yard zero would yield the following:

0-100 1.3 inches
100-200 0 inches


So where in there are you expecting to be working?

If you say "all ranges" then welcome to the party. This is why you need to know the bullet drop and the range before you engage a target. It also depends on how surgical are your requirments.

Me, I'd zero it at 100 and remember not to shoot any higher than the nose at close targets.;)

[jatx]

Me, I'd zero it at 100 and remember not to shoot any higher than the nose at close targets.;)

Thanks for the advice TS. :lifter

With my civilian weapon, I don't realistically expect to ever need to take a shot beyond 100 yards. With my issue weapon, who knows? My goal at any range is a solid CNS hit that will rapidly incapacitate even if the round fails to fully fragment.

[Peregrino]

C'mon guys - try the following search string:

http://www.google.com/search?sourceid=navclient&aq=t&ie=UTF-8&rlz=1T4DKUS_en___US202&q=M4+25M+Zero+Target+For+Iron+Sights

It gives you access to a lot of relevant info. In fact it'll connect you to the answers for most of the current questions.

NDD - FWIW I've seen a different 25M Zero target for the M4. It was not the same as the M16A2 target. The squares are not the same size and the aim point is different. You can use (everybody does mostly because they don't know any better) the M16A2 target; it doesn't make any difference except for the clicks to adjust and the POI (elevation - not critical at <150M especially with M68s/Eotechs). I've been looking for an M4 .pdf but haven't found one yet. The manual I've been able to access doesn't have the targets. I'll keep looking. Peregrino

[Gene Econ]

So where in there are you expecting to be working?
If you say "all ranges" then welcome to the party. This is why you need to know the bullet drop and the range before you engage a target. It also depends on how surgical are your requirments. Me, I'd zero it at 100 and remember not to shoot any higher than the nose at close targets.;)

TS:

I find it much easier to know the ordinate given a 300 elevation. About 6" at 160 meters. Go from there with holds until a fellow is under 30 meters and then it is either point of aim or hold about 3 inches higher than the impact location.

I spent a couple of hours on a KD range trying to figure out a true reduced 300yard zero. Closest I got was about 33 yards. I also shot two targets to show trajectory. Zeroed up at 300 pretty solid then shot the targets at 5, 10, 25, 50, 100, 160, and 200 as a graphic representation of trajectory of M-855 ball fired from a carbine.

Was pretty neat and if one has not done such a actual test, he will be very surprised at the results. Not what one would envision. It also provides a good challenge to those who are anal about shot placement as there is not a real big vertical spread so basically center hold is just fine from a barrel to 300.

Gene

[The Reaper]

TS:

I find it much easier to know the ordinate given a 300 elevation. About 6" at 160 meters. Go from there with holds until a fellow is under 30 meters and then it is either point of aim or hold about 3 inches higher than the impact location.

I spent a couple of hours on a KD range trying to figure out a true reduced 300yard zero. Closest I got was about 33 yards. I also shot two targets to show trajectory. Zeroed up at 300 pretty solid then shot the targets at 5, 10, 25, 50, 100, 160, and 200 as a graphic representation of trajectory of M-855 ball fired from a carbine.

Was pretty neat and if one has not done such a actual test, he will be very surprised at the results. Not what one would envision. It also provides a good challenge to those who are anal about shot placement as there is not a real big vertical spread so basically center hold is just fine from a barrel to 300.

Gene

Can you post the target, sketch the POIs, or describe the rise/drop from the various zeros?

TR

[HOLLiS]

TS:

I find it much easier to know the ordinate given a 300 elevation. About 6" at 160 meters. Go from there with holds until a fellow is under 30 meters and then it is either point of aim or hold about 3 inches higher than the impact location.

I spent a couple of hours on a KD range trying to figure out a true reduced 300yard zero. Closest I got was about 33 yards. I also shot two targets to show trajectory. Zeroed up at 300 pretty solid then shot the targets at 5, 10, 25, 50, 100, 160, and 200 as a graphic representation of trajectory of M-855 ball fired from a carbine.

Was pretty neat and if one has not done such a actual test, he will be very surprised at the results. Not what one would envision. It also provides a good challenge to those who are anal about shot placement as there is not a real big vertical spread so basically center hold is just fine from a barrel to 300.

Gene


Gene, are you familiar with the term "cone of accuracy" (I think that is the right term). It set a shooter up that between two ranges, the bullet will hit within a circle of a certain size diameter. Sort of saying what you are saying, If you shoot at center, your bullet will be in the kill zone. It maybe not be surgical or accurate enough for very long shots.

Basically the rifle is sighted in at center at a set distance, lets say 243 M. That from muzzle to 350 M the bullet will be within a 6 inch circle(cone) anywhere between those two ranges. For a hunter it takes range estimation out of the equation with in those distances.

H.

[Peregrino]

Hollis - The term/concept you are looking for is "point blank range" (http://en.wikipedia.org/wiki/Point-blank_range). Your "cone of accuracy" is another descriptor for "circle of probable error" and is just one of the factors in the study of external ballistics. I'm sure LR1947 or GE have a couple of lectures laying aroung they can dust off and entertain us with - personally I'm not typing that much again unless somebody is paying me :p . Peregrino

[jatx]

Can you post the target, sketch the POIs, or describe the rise/drop from the various zeros?

TR

Sir,

I did something earlier and added a 33 yard zero following Gene's post. Assumptions were as follows:

14.5" barrel
55 gr. Sierra FMJBT
Muzzle velocity 2861 fps
Sight height 3.0 inches

I hope this helps.

ETA: Axis labels got erased, but the vertical axis is inches of drop.

[HOLLiS]

Hollis - The term/concept you are looking for is "point blank range" (http://en.wikipedia.org/wiki/Point-blank_range). Your "cone of accuracy" is another descriptor for "circle of probable error" and is just one of the factors in the study of external ballistics. I'm sure LR1947 or GE have a couple of lectures laying aroung they can dust off and entertain us with - personally I'm not typing that much again unless somebody is paying me :p . Peregrino


Thank you............... For some reason your last sentence gave me the best laugh of the week, Again Thanks. BTW, I am keeping this short too.

[HOLLiS]

Sir,

I did something earlier and added a 33 yard zero following Gene's post. Assumptions were as follows:

14.5" barrel
55 gr. Sierra FMJBT
Muzzle velocity 2861 fps
Sight height 3.0 inches

I hope this helps.

ETA: Axis labels got erased, but the vertical axis is inches of drop.

Jatx, if you notice you have three possible zeros, where the bullet crosses the line of sight. Problem with using a close range zero, is that, the zero can be first crossing the line of sight, or the top of the arc of the trajectory.

[jatx]

Jatx, if you notice you have three possible zeros, where the bullet crosses the line of sight. Problem with using a close range zero, is that, the zero can be first crossing the line of sight, or the top of the arc of the trajectory.

Hollis, what I understood Gene to be saying was that he was looking for a shorter range zero that would come close to replicating the 300 yard zero, which would be pretty convenient. Maybe I misunderstood him, though.

Please clarify, how is a short range zero problematic so long as you are within max PBR (and you've assumed the right size kill zone)?

[Razor]

I've used this before for a 16" 1:9 m-4gery with decent results. I also have the article LTC Chuck Santos wrote on using a 50yd battlesight zero due to 2" or less deviation at all ranges to 250m. I haven't tried that yet, though, as I don't have a handy 50yd/200m range.

[HOLLiS]

Hollis, what I understood Gene to be saying was that he was looking for a shorter range zero that would come close to replicating the 300 yard zero, which would be pretty convenient. Maybe I misunderstood him, though.

Please clarify, how is a short range zero problematic so long as you are within max PBR (and you've assumed the right size kill zone)?


Jatx, Look at your graph. Two references, 1) where the bullet crosses the line up sight on a upward trajectory and then crosses the line of sight on the downward trajectory. 2) where the bullet ceases a upward path and starts to fall (top of arch) at the line of sight. Then note the difference in distance, and keep in mind, the line of sight is a straight line and bullet path is a arc. Also the distance from center of the barrel and center of the sights/scope come into play. The bullet initially needs to rise to meet the line of sight. Sighting in at a longer distance will insure the bullet crosses the line of sight twice. The first crossing is the short distance zero, the second crossing is the long distance zero.

I am not sure if that explains it completely.

H.

[The Reaper]

This is further complicated on the M-16 series weapons because rather than having sights directly atop the barrel, they are 1.4" above the bore.

TR

[Team Sergeant]

C'mon guys - try the following search string:

http://www.google.com/search?sourceid=navclient&aq=t&ie=UTF-8&rlz=1T4DKUS_en___US202&q=M4+25M+Zero+Target+For+Iron+Sights

It gives you access to a lot of relevant info. In fact it'll connect you to the answers for most of the current questions.

NDD - FWIW I've seen a different 25M Zero target for the M4. It was not the same as the M16A2 target. The squares are not the same size and the aim point is different. You can use (everybody does mostly because they don't know any better) the M16A2 target; it doesn't make any difference except for the clicks to adjust and the POI (elevation - not critical at <150M especially with M68s/Eotechs). I've been looking for an M4 .pdf but haven't found one yet. The manual I've been able to access doesn't have the targets. I'll keep looking. Peregrino


A target is nothing more than a physical represenation of a bullet strike at a given range. Personally I use a 1 inch pastie for 99% of my shooting out to ranges of 300 meters.

I also know there's a tgt made specifically for the M4 but as you found out is hard to find. The target I posted is off slightly for the M4 but will work fine for NDD's purpose. (and it free).

Not knowing the ammo type, exact weapon and personnel being trained I figured this target was more than sufficent.

I'm like Gene when it comes to rifle, all I need to know is where I zeroed (at what range) and make adjustments as needed for longer ranges as required.;)

Team Sergeant

Edit to add, if an individual is not keeping a shooting "log" with their rifle then I don't consider them serious shooters anyway.

[jatx]

This is further complicated on the M-16 series weapons because rather than having sights directly atop the barrel, they are 1.4" above the bore.

TR

Sir,

FYI, the free online JBM ballistics calculator allows you to correct for any sight height, which is pretty nice given the variety of mounts, optics and rail systems out there now. It also provides you with PBR and max PBR for any given size kill zone you wish to define.

[Gene Econ]

Can you post the target, sketch the POIs, or describe the rise/drop from the various zeros? TR

TR:

I will drop by the committee tomorrow and see if they still have my target. It was clear enough for photographs.

I have also done this on KD ranges using a 300 and 500 elevation with one hold on the target for each elevation.

These are great ways of showing shooters a true trajectory as bullet holes don't lie. What you see on paper is different than what you envision from computer programs.

Gene

[Gene Econ]

Gene, are you familiar with the term "cone of accuracy" (I think that is the right term). It set a shooter up that between two ranges, the bullet will hit within a circle of a certain size diameter. Sort of saying what you are saying, If you shoot at center, your bullet will be in the kill zone. It maybe not be surgical or accurate enough for very long shots. Basically the rifle is sighted in at center at a set distance, lets say 243 M. That from muzzle to 350 M the bullet will be within a 6 inch circle(cone) anywhere between those two ranges. For a hunter it takes range estimation out of the equation with in those distances. H.

Hollis:

I know a cone of fire which is basically the shot group size given a target that is vertical like a KD target. Beaten zone is that cone of fire when it hits the ground which is parallel to the trajectory. You are talking about a point blank zero given a kill zone size and the ordinate of the ammunition being fired.

The hunter still has to estimate range for his bullet to stay within his danger space. He has to be as anal about his range-e as his kill zone is small.

Gene

[Gene Econ]

Sir,I did something earlier and added a 33 yard zero following Gene's post. Assumptions were as follows: 14.5" barrel 55 gr. Sierra FMJBT
Muzzle velocity 2861 fps Sight height 3.0 inches. I hope this helps. ETA: Axis labels got erased, but the vertical axis is inches of drop.

JTAX:

My 33 yard estimate was about as close as I could get but in no way can I say it is perfect. It is probably within plus or minus three yards of my estimate though.

Try not to make assumptions unless you must. Those computer programs are not perfect by any means. Some emphasize trajectories to about 500 which gives error to ranges past 500. Others emphasize trajectories from 500 to 1000 at the expense of short range precision. Niether will give a perfect representation of what you shoot as ballistic coefficients change with speed. So there are errors involved. These programs will put you on paper at 600 -- generally within plus or minus 1 1/2 minutes. In other words they will give a nine ring elevation. At 1000 one must be on drugs to trust a PC ballistics program to give sufficient accuracy to have confidence a bullet will hit a six foot target frame. The problem is that the shooter doesn't know the time of flight of his particular load to 1000 unless he chronographs it at the barrel and then at 1000 enough times to trust his results.

One thing you should also watch closely is your perception of the path of a trajectory on your PC screen. Your trajectory must be exaggerated in order to show rise and fall on a short screen. It gives the user an illusion of a more parabolic path than the very flattened path found in reality. The computer programs are right, they just have to distort the trajectory to fit on a screen. Unlike the computer programs, shooting on KD ranges to see trajectory gives a very different picture. You will find that the bullet's rising branch is relatively steep for a short distance and then less steep to its ordinate. Past its ordinate it tends to drop relatively uniformly but not perfectly uniform, due to drag. It is really quite interesting to see the differences between reality and the graphics of a computer program.

Gene

[jatx]

JTAX:
It is really quite interesting to see the differences between reality and the graphics of a computer program.

Gene

Thanks very much for your insights. This is a fascinating topic and I appreciate your words of experience. I'm looking forward to getting back onto a .mil range this summer. :lifter