A chronograph is a device via which you can find out how fast your bullets are travelling. This is useful to the reloader in quality control and safety analysis, as well as accuracy. I personally got into the market for a chronograph so I could find out why my reloaded PS90 ammunition was so quiet. My theory was that I'd inadvertently worked up a subsonic plinking load without any appreciable kinetic energy.
Chronographs Have a Risky Job
Most chronographs, by their very nature, are constantly in the line of fire when in use. Optical-sensor chronographs have to be positioned downrange, and most shooters manage to shoot at least one chronograph within a few years of using them. Because it is necessary to send bullets between the supports and the diffuser on a chronograph, inaccurate shooting can readily lead to a bullet going through the chronograph instead of the empty space which it monitors for speeding bullets. Next to being a target stand, there is no riskier job for a piece of shooting equipment!
Magnetic operation: This is an alternative to the remote sensor operation below. If your chronograph uses a magnetic attachment, there's no risk that someone else will accidentally shoot your chronograph, and very little risk that you will.
Remote sensors: Some chronographs reduce the risk of expensive damage by relocating their electronics out of the line of fire. This is done by using wires (or RF, but this raises the cost of the electronics down-range) leading from the sensors to the electronics unit. The goal is that, even if someone in the lane next to you uses birdshot and scores a hit on your chronograph (or worse yet, decides to use your chronograph for a target), you will only have to replace the unit's sensors, not the timing apparatus and other electronics.
Companies Making Chronographs
Competition Electronics makes a few chronographs. I normally don't comment on a company's lineup, but it looks like the only thing CE chronographs have going for them presently (compared with other lineups) is their claim to have a larger sensor area. Otherwise, the chronograph designs look a few years behind the times for the price. It seems that they're primarily a remote control vehicle company, which probably means they don't worry about updating their chronograph designs.
MagnetoSpeed produces the only consumer-priced magnetic chronograph I'm aware of. It mounts to the front of your barrel like a bayonet, but uses two magnetic sensors to detect the a projectile moving out of the barrel. The only real drawback to this technology is that it's difficult to get a good reading on cast lead bullets. Copper jacketed, though, reportedly works fine. Another nice aspect of their system is the use of a standard MicroSD card for data storage. Using this, a nearly unlimited number of shot series may be tracked. Their current designs must be barrel-mounted, and hence generally won't work on pistols. See the review article for information on their chronograph.
Oehler Research makes a number of chronographs. They claim to be a de facto standard in military and industrial applications. As far as warranty goes, they have a 3 year limited warranty but will generally fix anything that breaks or wears out on their gear, regardless of age. However, it is expected that if you manage to shoot your chronograph, you will pay the actual cost of repairs. They also make a barrel-mounted pressure sensor and an acoustic scoring system (i.e. a set of microphones which can identify where a bullet is hitting within a target area), and have some Windows software which predicts downrange performance of your loads, either using your measured speed as a basis or completely made up. As of 2007, the only source for Oehler's non-industrial chronographs was the used market (they were concentrating on their industrial gear). However, production of the model 35P was resumed in 2010 and has continued through at least 8/2012. Information on resumed production contributed by a reader
PACT makes a variety of chronographs. They don't list how many entries their units can store, but they do seem to throw in a lot of calculations.
RCBS is releasing their Ammomaster chronograph in February 2008. Based on the pictures, it bothers me to say this but I think even the Competition Electronics Prochrono Pal looks like a better product. Unless the sensor arms are going to be huge (and the CAD diagrams look like they won't be), the Ammomaster looks like it has a much smaller hit area than other chronographs, and no remote feature.
Shooting Chrony produces inexpensive chronographs which fold up into a compact form factor. Although light on features, they're also light on price and probably are the best choice if you fear you won't be the only shooter using your chronograph. You may also consider it wise to own one which you can loan out instead of your prized and much-more-expensive chronograph.
RSI is primarily a software company, and pretty much everything they make can be plugged into a PC. This includes their chronograph and chamber pressure sensor. They claim their chronograph's accuracy has been tested/demonstrated to be 0.3% better than an Oehler (but not which model of Oehler). They also make a product called Loadforce (discontinued; being redesigned), which senses recoil and the neck tension involved in seating a bullet.
This section links to any reviews of chronographs in the Gunwiki web.
I reviewed a [ReviewMagnetoSpeed][MagnetoSpeed v1]] chronograph a while back.
Over the past few days, I've been looking around at chronographs and have yet to find a good comparison chart amongst models from the same vendor, let alone the numerous vendors in the marketplace.
Remote display available, but electronics remain downrange. Also serves as shot timer; 100 string mode cancels timer ability. PC connection.
Shooting Chrony units apparently have custom options available. Each base model can be upgraded to a 'master package', which adds a remote control with close-up read-out and 18 ft cord.
No, also N? for products where I'm not sure
N/A, 'Not Applicable'
MSRP Date: This is the date at which the MSRP was recorded. Because Gunwiki articles don't get re-edited every time an MSRP changes, this is here so that outdated prices at least stand out as such.
6*10, indicates that the unit will store six strings of 10 shots apiece. A string is an individual set of shots.
50*10/100*10, is encountered only in the Gamma Chrony, which allows the user to set how much memory to use for shot storage and how much to use for shot timing. It may be partitioned however the shooter sees fit.
Y/#? indicates that the product has memory, but the manufacturer doesn't say how many entries' worth.
PC indicates that, while the product doesn't support a printer directly, printing is possible via the PC connected to it.