Which is the best rangefinder for 500-600 yards?

The answer depends on the purpose of your rangefinder and your own requirements. For bow hunting, 100 yards is more than enough. On the other hand, for rifle-hunting you, the range will vary widely depending on where, what and how you hunt and on your proficiency and style. Typically you are looking at a wide range of 200 yards to 800 yards. For golfing again, it depends on the circumstances. You can work with a rangefinder with a range of anywhere between 200 yards to 600 yards. The yardage described here is relative to dark trees. Do not forget to find out what the advertised yardage is relative to - specifications can vary from highly reflective surfaces to deer sized targets.

Sig Kilo 2000 Rangefinder
Sig is famous for its high-quality product, and Sig Sauer 2000 Kilos Rangefinder is no different. This rangefinder is being picked by most of the hunters and shooters for its 1000+ yard range which enables you to have the best hunting experience. But that is not all. The Sig kilo 2000 rangefinder review describes more about it.
The Sig Sauer Rangefinder consists of a Cordoba protective carrying case, a lanyard, battery, a manual for guidance and a box for protection. The size of the rangefinder is possibly same as the size of your palm which is very convenient to use. The specifications of this rangefinder are as follows:
Specifications

• Magnification Range: 7x
• Finish: Matte black w/Rubber
• Objective: 25mm
• Eye Relief: 0.59" (15mm)
• FOV: 34.6' @100 yards
• Max Range: 3400 yards on Reflective targets 1500 yards on trees1200 yards on deers
• Reticle: Circle with data
• Battery: CR2

The Ultimate Bushnell Scout DX Rangefinder
The Bushnell Scout 1000 is a pocket-sized laser rangefinder that offers a 5 - 1000-yard range with a +/- 1-yard precision in 3 diverse targeting modes: Scan, Bullseye, and Brush. The Bushnell Scout DX Rangefinder provides compact and lightweight design along with high-quality visuals to its 5 by 24-millimeter multi-coated optics.
It comes with a hard construction, water resistance, diopter adjustment, roll-down eyecup, a handy tripod mount, and features the ARC method with built-in inclinometer so you can get accurate distance on downhill or uphill shots.
Bushnell claims it will range a deep target at 1,000-yards, trees to 650-yards and a deer at 325-yards. It has a 6x21mm monocular for inspecting and aiming, weight 13.6 ounces and takes up 5.5 x 5 x 3-inches of space. There are a Cardura case, neck strap, and CR2 battery contained in the box along with a cloth to clear the instructions and clean the lens.
The ABS case has adequate non-slip surfaces to help users grip it securely, and there is a tripod hole if you want to have it in a stable position for some time. At this stage of our Bushnell Scout DX Rangefinder review, we will talk about the design of the rangefinder.
The Scout DX 1000 is a smooth and compact equipment that shares a similarity to the high-end G-Force 13000-series from the identical manufacturer. In addition, the best range finder has rubber armoring which provide a smooth and certain grip even when things get wet.
In fact, the Scout is fully water and fog proof which has a massive advantage out in the field. The Scout DX Rangefinder also has a flexible tripod mount that is placed into the bottom of the rangefinder.

Sig Kilo 2000 Rangefinder
Sig is famous for its high-quality product, and Sig Sauer 2000 Kilos Rangefinder is no different. This rangefinder is being picked by most of the hunters and shooters for its 1000+ yard range which enables you to have the best hunting experience. But that is not all. The Sig kilo 2000 rangefinder review describes more about it.
The Sig Sauer Rangefinder consists of a Cordoba protective carrying case, a lanyard, battery, a manual for guidance and a box for protection. The size of the rangefinder is possibly same as the size of your palm which is very convenient to use. The specifications of this rangefinder are as follows:
Specifications

• Magnification Range: 7x
• Finish: Matte black w/Rubber
• Objective: 25mm
• Eye Relief: 0.59" (15mm)
• FOV: 34.6' @100 yards
• Max Range: 3400 yards on Reflective targets1500 yards on trees1200 yards on deers
• Reticle: Circle with data
• Battery: CR2

Simmons Laser LRF 600 Rangefinder

Treestand bowhunters are known to be the people with particularly discerning preferences when it comes to shooting. If you are one of them, you surely are proud to make an accurate hit at extreme angle.
So, you know how important the difference of a few yards between the true horizontal distance and line of sight distance is when a successful hit is the only thing you want. Well, forget all these subtleties because Simmons Laser Rangefinder LRF 600 is there to help.
Alongside the reticle and battery level indicator, this budget-friendly rangefinder might seem a compromising model due to having no rifle, or bow, or target priority icons. After all, this model is ideal for shooters and hunters.
Important Highlights

• Accuracy: +/- 1 yard
• Range: 10-600 yards
• Monocular Optical System with a fixed focus
• 4x magnification
• Liquid crystal display
• Line of sight measurement
• Tilt Intelligence (For displaying True Horizontal Distance)

Sig Kilo 2000 Rangefinder

Sig is famous for its high-quality product, and Sig Sauer 2000 Kilos Rangefinder is no different. This rangefinder is being picked by most of the hunters and shooters for its 1000+ yard range which enables you to have the best hunting experience. But that is not all. The sig kilo 2000 rangefinder review describes more about it.
The Sig Sauer Rangefinder consists of a Cordoba protective carrying case, a lanyard, battery, a manual for guidance and a box for protection. The size of the rangefinder is possibly same as the size of your palm which is very convenient to use. The specifications of this rangefinder are as follows:

Specifications

• Magnification Range: 7x
• Finish: Matte black w/Rubber
• Objective: 25mm
• Eye Relief: 0.59" (15mm)
• FOV: 34.6' @100 yards
• Max Range: 3400 yards on Reflective targets
• 1500 yards on trees
• 1200 yards on deers
• Reticle: Circle with data
• Battery: CR2

Bushnell Scout DX Rangefinder is a good one for golf.
It's a fantastic rangefinder.
It offers some amazing feature and specification like...

• 6x magnification.
• Range between 5-1000 yards.
• 3-volt CR2 Battery.
• Rangefinder Accuracy 5 yards.

The Bushnell Scout DX Rangefinder will help you to pick from 3 different user modes by pressing the Mode button at the left side of the unit. First is the usual mode which can be used for most purposes up to 1000 meters and works well towards the pretty reflective surface.
When turned on, the Scout 1000 Laser Rangefinder liquid crystal display (LCD) will directly display icons like the bow and rifle mode. The bow mode will provide you with true horizontal distances from 5-99yd away, depending on the angle. The rifle mode, however, will permit you to get the angle and drop/holdover of your shot to the target from 100-800yd.

There are two different sub-models of the CRF 1200. The 527 reads in meters while the 523 reads in yards. This is not something that can be changed by the user.

I got one for Christmas 2010. Also found that it is off by 10 yards compared to several other rangefinders/gps units.

I would send this unit in for repair to have it inspected you can reach their customer service at 800-423-3537 option 1.