# The C79 Optical Sight



## Jebus (13 Mar 2011)

Does anyone know, at what range are the sights zeroed in at? 

I tried searching but with no luck.


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## Lerch (13 Mar 2011)

Might vary from unit to unit, but usually 200m (lowest adjustment on the dial). Makes sense that everyone would do the same...


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## Jebus (13 Mar 2011)

Alright, thanks! I figured it would be around that range but not sure.


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## brihard (13 Mar 2011)

The scope is mounted on a mount that allows for specific preset elevations calculated for our ammunition through our barrel. A C7 using the C79 sight should be zeroed such that, at 200m, your point of aim is the same as the point of impact. Since we tpyically zero at 100m, we zero it so that the point of impact is 50mm above the point of aim. With the sight set at 200, this means you get two distances where the bullet passes exactly through your line of sight- at 200m, and, if I recall, at about 54m as it's still rising. 

For different distances, you can either aim a bit high, or if time allows you can turn the dial on the sight to a greater distance. This will not get an exact match to point of aim/point of impact, as each firer will shoot slightly differently, and it cannot be assumed that the points of aim and impact will match perfectly at a distance other than what the site is zeroed at. But unless you're an incredible shooter, this variance will probably be smaller than your grouping size anyway.

Speaking for myself, except for on a specific controlled range where we're given the command '300' or what have you, I pretty much always just aim the rifle high a snitch at greater distances. Within the effective range of a 5.56mm round it doesn't require much aiming off to adjust for elevation the old fashioned way. two or three inches will suffice for 300.


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## Sig_Des (13 Mar 2011)

I would personally like to see us start teaching people how to manually adjust the Scope themselves  (not just have an A/RSO walk up and fiddle with your scope for you, as happens on every range), teach them how to use it open gate, and have people record and mark their scopes appropriately.

Ie: On my issued rifle with my scope, by a quick check of my shooting log, I am zeroed at 100m, with a paint marker mark on that notch.

@200M, 1-click up (counter-clockwise) for PoA/PoI

300M, 3 more clicks up

400M, 2 more

500M, 4 more

Each of these are marked, and I know the clicks sound out of whack, but on that particular rifle with that particular sope, I'm good to go. I have a second rifle that's issued to me as a back-up for Service Rifle competition, and the number of clicks are a little different on that one's scope for me, but they're all marked. What a lot of people don't realize is that with the C79 dial, not all the marks are accurate. It's a rough increase. I know that my open-gate increments are nothing like the scopes increments closed gate.

I know what with these days being what they are, it's unrealistic for everyone to do a 500M walk-back, but it'd be nice for people to know how to properly use their equipment to the fullest extent of it's capabilities.


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## Seyek (14 Mar 2011)

I can't speak for everyone, but even as a reservist on BMQ we were all taught how to zero our sights and I've done so myself every time I've had too, same with all the guys I can think of in my unit. 

I had assumed this was the case with everyone, at least combat arms wise.


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## Sig_Des (14 Mar 2011)

I dunno, maybe it was just me, but just about every range I've been on, I've seen individuals fire their grouping, put up their hand, tell the A/RSO where the grouping is, and seen the RSO do the adjustment for them. Not saying it's everyone, and maybe it's just coincidence for me, I'd just rather not see it at all.


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## Illegio (14 Mar 2011)

During Combat Support's IBTS training last fall, the snipers set up an unknown-distance range that the whole company rolled through, the winner picking up a day off at the end of the week. You want to teach guys to use 1/4 mil corrections on the C79, well, you better teach them how to judge distance first, and not that "multiplying known distances" or "appearance method" crap! I saw guys dialed up to 600 on their sights, when I believe the furthest target away was something like 450 max. I don't think it came as any great surprise to anyone when a sniper and a guy from recce tied for top shot. Actually take the time to teach the WERM rule, break down the C79 reticle (for what it's worth,) give people the opportunity to apply those lessons, and provide incentives for those who actually give a fig.

Or don't, and let's forget about all this nonsense and go back to business as usual.

/rant

All that being said... The way the system is geared right now, in terms of maintenance training and PWTs and all that, having people fiddling with "open gate" sights and corrections is almost more trouble than it's worth. It's definitely not something I would consider using during the rundown on ye olde PWT3. There's nothing inherently wrong with giving people the information and training to better themselves on the range, but there are a lot of other things that need changing to make that worth doing.

As far as ARSOs doing all the legwork when adjusting sights and the like, I suspect that's just a product of PLQ Mod 3 and IPSWQ Small Arms Coaching. Some instructors on those courses want you to do all the work, and others are more... egalitarian. It carries over.


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## Nfld Sapper (16 Mar 2011)

Thought that's why we use colimeter (spelling?) to record the exat zero of each firer....


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## Veiledal (16 Mar 2011)

The culminator is just a rough zero, getting rounds on paper and adjusting is a more accurate way. We use the culminator before going to the range so we do not waste as many rounds trying to zero the weapon. That is what they taught us on DP2A


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## aesop081 (16 Mar 2011)

Collimator


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## NavyShooter (17 Mar 2011)

That unknown distance range sounds like it would have been fun to try  >

The "Open gate" method is excellent for shooting teams.  I don't suggest it be used otherwise.   It is a method that allows the shooter to correct for the pre-calibrated elevation drum not being perfectly matched to individual ammo/rifle combinations.  

I will harken back to the days of the Iron sighted C-7 for a moment.  

Back in those days, there was considerable effort and thought given to how best to setup the non-adjustable sights for varying engagement ranges.  The "best" compromise seemed to be a 400 meter zero.  

This resulted in the following elevations:

100m  7" high
200m  11" high
300m  9" high
400m 0
500m 18" low

Relating this to targetry, between 100 and 300m, aiming at the bottom of a figure 12 would drop the rounds into the face (between 7 and 11" above your aiming point).  That means that for most of the shooting you do, your MPI will be centered within the same 4" vertical area.

At 400m, your rounds hit where you aim.

At 500m, cover the figure 12, and your bullets will drop into it  (ok, into the bottom of it, the Fig 12 is only 22" tall, but if you frame the front sight on the 4 foot screen, it works well.)

How does that relate to the Elcan?  Well, the first year I shot an Elcan, I zeroed at 400m and didn't adjust the elevation drum at all.  Worked out alright.  I later learned to use the Open gate method.

This technique may also be known as a 6'o'clock hold zero.  

YMMV, but there may be some value in a history lesson.

NS


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## shooked1 (17 Mar 2011)

I am fairly new to shooting could someone please elaborate on what open gate means.


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## Illegio (17 Mar 2011)

I couldn't find a good picture of it, but on the C79 below the eyepiece there is a dial with a silvery little switchy-thing, or "gate." When the gate is down, or "closed," the dial functions as a bullet-drop compensator, meaning you need only set the range on the dial and the sight will (roughly) add the appropriate corrections to hit the target at that range. When the gate is up, or "open," the dial turns in .25 mil increments left or right, corresponding to down and up respectively. This is generally only used to zero the sight to a specific range (generally 200m) after which the gate is closed. Some folks, such as the CFSAC teams, prefer to use the sights "open gate" all the time, however, as it allows a more precise adjustment of the sight, if you know how many clicks you need to raise or lower it for a specific range.


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## RonaldDoyle (31 Mar 2011)

The C79 Sight is the only real different feature between C8  and M4.


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## Dissident (31 Mar 2011)

RonaldDoyle said:
			
		

> The C79 Sight is the only real different feature between C8  and M4.



I hope this was more of a question than a statement.


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## MikeL (31 Mar 2011)

RonaldDoyle said:
			
		

> The C79 Sight is the only real different feature between C8  and M4.



You might want to sit the next couple rounds out there champ as you are out of your lane. More reading, less typing for you, especially when it comes to things you don't know much about.


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## Sig_Des (31 Mar 2011)

Dissident said:
			
		

> I hope this was more of a question than a statement.



If it was a question, question mark fail.

If it was a statement...knowledge fail.

Either way....fail.


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## BadEnoughDudeRescueRonny (11 Sep 2011)

RonaldDoyle said:
			
		

> The C79 Sight is the only real different feature between C8  and M4.


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## JSR OP (11 Sep 2011)

Hmmm...  I looked up 17 Halpin Ln, Ridgefield, CT 06877 as is used in this guy's  profile, and its a very popular address.  Many forum posts with only one single post by the user in each.

things that make you go Hmmmm......


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