I been wanting a holosun 503 bu, gu, or cu for sometime now but been doing my relentless research, and so far, I am thoroughly impressed.   I think they are pretty incredible actually with the features and technology they offer.  

Im still up in the air whether or not I want the solar option because I am unsure if you can turn off the auto dimming feature.  I dont like that.  Any input?

Anyway.  I would like to see some pictures of a mounted 503 series, now if you have a magnifier behind it, that would just blow my load.

Thanks.

Also, I know they are made in china, I know they are not an aimpoint.  Save your breath die hard fans, -no disrespect.   I would like one, but cant justify spending that kind of money on a recreational rifle.

First, the solar cell does not power the sight without the battery.  None of mine with solar cell will turn on or operate without battery.

What the solar cell does is sense ambient light and adjusts the brightness of the reticle accordingly.

What, you don't like that feature?  No problem.

To switch to "manual" mode, press and hold the + button until you see the reticle turn off and turn back on.  This will take about 3 seconds
of hold, and the reticle will blink off for about 1/2 second.  When it comes back on the sight will be in manual mode at a medium level.  You
may set brightness by pressing the + (brighter) or - (dimmer) buttons until the desired brightness level is reached.

I don't have photos now, but can take some tomorrow.  I don't have the 503C... I have the 515C, which is the same except the front and rear
tubes are extended slightly so that lens covers can be attached.  Also, the base has a quick detachable latch.  That latch has a latch so it
cannot likely be opened accidently.  There is also a "kill flash" grid which can be screwed into the front.  This grid stops reflections back in
the direction of the target.  

The 503C does not have the kill flash, lens covers, nor the quick detach base.  But all other features are the same, that is, they operate the
same.

Using the supplied 1.6" base gives lower 1/3 cowitness with regular AR-15 sights.  All of my AR-15's use the F marked front sight base, with
Magpul polymer BUIS.  I get a good co-witness below center looking through the BUIS and through the Holosun.

I have one 503FL, which has the low mount, no solar, mounted on a Mini-14.  It is all manual brightness operation.  It has the lens caps and kill
flash.

For all of these, if you want to use a dot-only, you can turn off the circle.

When I sight in a 500 series Holosun at the range I switch to dot-only reticle, and switch to manual brightness.  This lets me reduce brightness,
and also apparent size of the dot for more precise aiming.  After sight in, I switch back to auto brightness and circle-dot reticle.  

I never turn them off.  They don't need to be turned off.  They are always ready.  In 2 years I'll change the battery.

I really like the reticle design of this red dot.. especially for a rifle used for short to medium range. I also like the auto-on function by the slightest movement. I'm just wary about having it on  HD rifle. I know everyone will say to go with the AP, EoT, Trig , etch, but those don't offer the reptile, battery life and compactness.

The 503C and 515C (function identically) do not have the auto-on.  You just never turn it off.  It's always ready to go.  
Have you not read the comments about the very long battery life of the Holosuns?

And I certainly do keep an AR-15 with Holosun for home defense and no qualms about it.

The GU and BU has motion activation.

Yes, but they don't have the auto-brightness adjust.  When you put a 503C or 515C in the closet or safe, the
auto-brightness turns the LED to almost off, NV levels.  There is almost no current drain.  Even if you didn't,
current drain is very low and you have a couple of years of battery life.  I simply mark the month and year of
date in service on the battery with a sharpie, 8-16.

I also have a 503FL which is similar to the GU, no solar, battery on the side, motion activated.  With that one,
too, I don't worry about battery, just change in a few years.

Regardless of which model you get, I think you'll like the circle-dot reticle (like Eotech), and you'll like this
sight.  As I said, if you don't like the auto-brightness, it can be switched to manual.

Jup

I get it, it has a pretty long battery life, but it appears having the motion activation with realistically extended its usage.

I read of some complaints about the auto brightness not being bright enough for certain users. Could be subjective due to everyone's eyes. I personally like 1 setting and go.

I just don't see it as a con having auto activation.

Thanks a lot for that thorough post.

So that swayed me back to the solar option,.  I watched a few you tubes of people taking their batteries out and actually using a flashlight to power the reticle through the solar.  Suppose a phone call is needed to holosun.

Any work with a magnifier? I'm wondering how sharp the reticle appears in front of a 3x magnifier

None of mine will do that, that is, operate without the batteries.  The only Youtube videos I've seen using flashlights just showed the
reticle getting brighter or dimmer from the amount of light on the solar cell, as demonstrated with flashlight.

A96HondaAccordEX, again, it is as simple as (a) switching the 503 from auto to manual as described in my earlier post.



And if in manual mode:



To turn back on it takes only a quick click of the + or - buttons.

Or you can buy another model, such as the 503GU.

503C on a LaRue QD absolute cowitness mount

Such a sharp looking optic.  Nice setup.

I have a Sig Arms Romeo4c which is basically the same as the Holosun.  And it DOES operate without a battery installed.  In fact while I was checking it out in Riflegear, both I and the salesperson thought there was a battery installed until we actually checked.  In bright light it works very well.  But with low light it is pretty much useless since it doesn't have an etched reticle.

If it had an etched reticle, it would be an optical / prism scope, and would not be as forgiving on eye placement or eye relief as a holographic red dot.

Plus be about a 12-16oz optic.

Vortex Spitfire 1x prism is 11oz

Just to be sure I wasn't spreading any misinformation, I just went and yanked the battery out of HS515C and yes, it does indeed function without the battery installed.  Pretty cool feature...

I have 3 503c's and like them. As has been mentioned, the 5xx "c" (solar panel) models will NOT run w/o battery. As poster already mentioned, the panel is a "sensor" to adjust auto (mode) brightness settings. Keep in mind that Holosun is a Chinese manufacturer, and their "instructions" show that they translate poorly to English. I think they mean to describe the "auto mode" NOT as solar powered, but solar REGULATED. I really wish Holosun would hire someone to rewrite their manuals properly for English... but it is what it is. They are very durable units (4xx and 5xx models) and are very friendly with the battery life.
Some people (such as James Yeager) did a video of the 503c and thought it would run on (just) solar because they didn't install the battery yet and it worked. That is false, they will not. What they haven't figured out yet (yeager) is that some retailers (such as PA) pre install the battery before sending the unit (D'oh!). Another common complaint is the "it wouldn't work even after battery install"... this is because they put the battery in wrong. With the undertray battery models (all the "C"/solar sensor panel) the battery goes in UPSIDE DOWN. Poof! Problem solved.
They are a fantastic sight, and a great bargain. Buy with confidence.

I got mine recently for 180. 503c and it DOES run with NO battery.  I haven't had a chance to use it but it seems pretty legit.

SLR mount is sexy time