538002-SSI ProChrono Digital Chronograph

We've all probably been to the range & seen the guy who brings a full-size truckbed full of range gear & a quart of coffee in a thermos. He sets up & sits for hours obsessively shooting hand-polished reloads, from a bull-barrel rifle mounted in a bench vise, & then occasionally makes minute adjustments & written notes in an attempt to gain more accuracy from his rifle (even though he couldn't hit the broad side of a barn shooting standing offhand).Yeah, you don't need to be that guy to enjoy this chrono. No offense to the bench-rest hand-loaders, but you don't need to be a range wonk to get use out of this chrono, to enjoy it, or for it to provide you valuable information.I've had two of these chronos, & I like the latest model even more. Right out of the box, with no reading of instruction, I found the unit intuitive-enough to use immediately. It's reliable & seems to measure even the smallest/lightest .22LR shot from a pistol. For example, I tried some odd 20 grain lead-free "green" rounds & even their velocity measured with no problems. The unit will give you nine strings of shots, & will tell you the velocity of each individual shot, the average, the extreme spread, & the standard deviation. You can also easily delete strings or fliers (individual shots that are way outside the norm).One suggestion I'd make to get the most use out of the unit: Buy a nice & tall tripod, & set the chrono up on it in a way where you can line it up with a target or two. If you're focused on determining fps, you can simply shoot blind through the gates. But since you're burning up ammo, might as well do some target shooting while you're at it. I find the gates large-enough to casually shoot pistol through without worrying about shooting the metal rods.I can't say enough good things about this chrono. It's been very educational to see the differences between different ammo types. For example, I found a 200 fps difference between two brands of ammo even though they both featured 180 grain JHP bullets. It's also been interesting to see how one box of ammo-- from one manufacturer-- can have so much of an extreme spread. I shot a box of American Eagle 180 grain FMJ rounds and there were some really wild variances. Some rounds were clocked at 950 fps, & several fliers were clocked at only about 500 fps. I'll never buy that brand of ammo again. Too inconsistent.One last suggestion: To protect the unit, keep the muzzle 5-10 feet back from the display & the front gate. Aside from causing erroneous readings, you don't want your muzzle blast to dirty up the unit or destroy it.

So, I ordered this so I could check my velocities for reloads, and everything arrived perfectly. I was happy to see it was easy to use and I could read the data from about 5 yards, which is where I wanted to set the chrono' up, on a small tripod, so I would get a good reading without muzzle blast but not have to get up every shot to read the thing.And it absolutely worked perfectly, right out of the box ... HOWEVER ... on the 7th shot testing ammo from my AR 6.8 build, I aimed at the lower right hand square on my target board, without ever re-setting my scope back to low power to check line of sight things ... and ... well ... ya know ... the dang bullet leaves the barrel about 3 and 3/8" under my line of sight. Of course I know this ... but I wasn't thinking about what that meant at 5 yards.Yep, I really did that! I actually shot it lengthwise about 1/2" below the top rim of the case (you can see the bullet trace marks on the outside of the top cover from the bullet passing inside), and blew a nice extra wound hole out the back. Messed up the inside pretty good.If we were hunting, I would say it was a really good exit wound. Heh heh!Oh, and of course, all of this happened out in the woods, with a whole bunch of ammo to check.So, here's the real basis for the 5-star, besides all the good stuff and excellent service.Do you think it still works? Yes it does, and it is still very accurate based on factory loads and known loads I have checked!!I actually repaired the thing out there with painters tape and a small screw driver. Thankfully all the damage I did was to the case and the reflector holders and lens cradles, and I was lucky I didn't shoot through any electronics. When I got back home I cleaned it more thoroughly and repaired the case and internal supports and cradles with aluminum tape, and have used it a few times since without issue.Of course, now I set the tripod a little lower based on my line of sight now. Doh!!Dawg says ... I'm a dum*a**, but this chrono' is awesome!

These chronos are a must if you tune airguns. Work well as long as you understand there quirks and limits. I was surprised at the consistency this reads. Nice to confirm what I believed was happening with my airgun. Price is very good for what you get.Update. I just love this thing to death. I have used it to tune my Hatsan AT-44 with a regulator. It now shots a consistent 910 (+/- 3 fps) for 30!!! shots. last 10 fall off by about 5 fps per shot. I could not have accomplished that feature without this chrono. I also used it to "tune" my Beeman p17. after trying several pellets I have a great idea of what to use for any application. This sets up in seconds and sips battery life (over 500 shots on one battery). I use an old busted up camera tripod to hold it and have not had any issues even in slight breezes. I honestly have only had a couple of shots not register (usually on a very cloud day or in sun/shade situations). This is a great chrono.