Having never had a chronograph some 30 years ago when I was first getting into reloading, I started looking at what was available now having gotten back into reloading again. I recently started working up some new 9 mm and .45 ACP loads for my Springfield XD pistols. I also wanted a timer for use at the range as well as dry practice at home.
My buddy had a small range timer that he was quite happy with but I needed my
reading glasses more than I cared to admit when I used it. I decided to
find something with a larger display. The physical size of the timer
wasn't really an issue either. One evening, a Google search turned up the
PACT web site and after reading some forums threads about it, I decided
to give the MKIV-XP Championship Timer and Chronograph a try. I could
satisfy two needs with just one device (or so I hoped). And that is how I
ended up with the MKIV-XP unit.
By consumer electronics standards, the appearance of the MKIV-XP is quite old school. Don't get me wrong, there is nothing wrong with old school when it serves its purpose, which I believe this one does. I fully enjoy it NOT having a keypad that is as tiny as that on my cell phone. I also appreciate being able to read the old fashioned 2 line LCD display without having to put my reading glasses on. While there is a menu or two, I like not having everything buried underneath a couple of menus that require multiple arrow key presses in order to find and change a commonly used parameter.
The MKIV-XP contains non-volatile flash memory and gives you
automatic storage of your timer and chronograph shot strings. You can
turn the unit off, take it home, and turn it back on and review the data
accumulated at the range. The strings and shots going into memory are
automatically numbered so you don't have to fuss with that while at the range. When you fill the memory, it deletes the oldest
string in memory to make room for the one it just created. The user manual
does not specify memory size nor how many shots can be stored in memory.
The back panel provides jacks for the chronograph's sky screens, labeled STOP and START. PLT1 and PLT2 are used when shooting steel plates. They can be used to trigger the timer to show which of two shooters drew and hit their plate in the shortest time. The AUX connector is a 5 volt output jack that can be used to drive a small relay that can be used to sound a horn, control a turning target, or perhaps illuminate a light. Adjacent to the AUX connector is the USB port that provides a connection to your PC or laptop when you wish to download range data.
PACT states that the MKIV-XP will work with all PACT and Oehler skyscreen systems. Since I had neither of these from a previous era, I ordered a pair of the PACT MKVI skyscreens from their web site.
A box with all of the skyscreen pieces and parts arrived the
following week and I removed them from the shipping box to ensure everything was
there for Saturday's range trip. The detectors slip onto the aluminum
mounting rail and are held in position (which results in exactly an 18"
separation) via a spring loaded detent. The side arms can be easily
attached and removed from the detectors and the diffuser screens are held in
place by several tabs on the end of the side arms. The entire assembly can
be assembled or broken down in under a minute.
A recently purchased tripod (for my camcorder) was more than sufficient to hold everything in place while allowing ample positioning of the skyscreens for reliable bullet detection. At a minimum, you'll need to be able to adjust the elevation and the tilt (fore and aft) of the skyscreens.
Each detector has a cable attached to it that is terminated in
the plug that mates with the connector on the rear panel of the MKIV-XP.
The owner's manual does not specify an optimum distance for placement of the
skyscreens from the muzzle of the firearm. I experimented with 8~10 feet
and that seemed to work well. The manual does mention the problems you can
experience from muzzle blast and so obviously you can't have the skyscreens
parked right off the end of the barrel. After a couple of trips to the
range, I've found 10 feet to work well for my handgun shooting.
The manual does caution against shooting the detectors. You are encouraged to "aim in such a way that the bullet passes over the center of each screen at an altitude of between 4 and 8 inches above the sensor and centered". Folks with a high profile scope might want to take that into consideration when setting up the tripod for proper height. I've read on more than one forum the accounts of rifle shoots putting a shot through the hardware as they sighted through their scope.
4x4 Off-Road Homestead Firearms RC Flying