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Is there a good chronograph available for around $100.00?

James

I use a Chrony and have made a metal shield that I use when testing
shotshells to prevent a wad from messing up the front of the Chrony

http://www.midwayusa.com/product/531741/shooting-chrony-f1-chronograph

Joined: 03 Feb 2014 Posts: 325 Location: West Texas

I have the ProChrono. It's a nice easy to understand unit, priced right, and it appears to work well. I have measured rubber bands (42 fps), .177 pellets (950 fps) and a few variations of my 16 gauge low velocity load. (1050 fps). You will need a camera tripod or equivalent to hold it. I sat in a chair and shot thru the screens from a distance of 3 feet. No damage done. But I do need to replace those metal sky screen rods with wooden dowels.
I haven't used it much but I am impressed. It worked great on a sunny day with the sky screens. Just make sure you turn it in a position where the screen shades the lens in bright light.

https://www.amazon.com/Competition-Electronics-Prochrono-Chronograph-Purchasecorner/dp/B00HYQ39G0/ref=sr_1_4?s=sports-and-fitness&ie=UTF8&qid=1468110968&sr=1-4&keywords=chronograph

Joined: 26 Apr 2010 Posts: 3177 Location: NCWa

I have used a Chrony for about 20 years and it works well. The three limitations are: 1. Exposure to the shot/wad because the unit is just a few inches below the path of bullet/shot; 2. Limited accuracy since the distance between start and stop is only about a foot (compared to several feet in bigger units, and 3. the unit needs to be close enough to be able to read it, so you're pretty much limited to about 15' from muzzle.

While the accuracy may not match the higher priced bigger units, it does seem to be accurate within it's measurements, so while the actual velocity of a load may be off a little, the comparison of loads seems to be accurate. that is to say, one load may register 1300 fps and another may register 1350. the actual velocities might be off by 20 fps, so instead of 1300 and 1350 I'm actually getting 1280 and 1330; but the difference is that the one load is still 50 fps faster than the other.

So if you can keep from blowing the unit to smithereens and you can read the numbers from a short distance- then the Chrony is a very useable unit. Actually, I think there are newer units that have sender/receiver units so that there is a screen right on the bench- but what I have has worked. as said for several years.

I have had the same Pro-chrony for 15 years. It is still accurate and works well for BBguns, rifled bullets, and shotguns. I attached two clear hard plastic plates in the front to deter shotgun pellets from damaging the unit; and the plates have saved it numerous times.

Joined: 15 Jun 2010 Posts: 1358 Location: Twin Cities, MN

I have had an F-1 Shooting Chrony for several years and it has served me well. Just gives velocity of each shot, so have to record it and do stats later if you wish. I would recommend the Alpha Master Chrony as it has a corded display and does all of the basic statistics for you.

http://www.shootingchrony.com/products_SCMMCM.htm

When I chronograph loads I always shoot a factory load that I have used in the past as a reference. I use the shades and place my muzzle 5 feet from the first screen. Consistency in your setup is key to being able to compare findings from different sessions. Mine's been rock solid and very useful.
Jeff

Guest

Dave and Jeff -- Why 5 feet? Pray tell . . .

Thanks.

Guest

Joined: 15 Jun 2010 Posts: 1358 Location: Twin Cities, MN

What Dave said. I get readings very consistent with Win AA factory ammo claims. Some folks recommend 3 feet, but I can see the muzzle blast really hit the machine at that distance. Again, I think consistency is key.
Tony, what distance do you use and why?
Jeff

Joined: 03 Feb 2014 Posts: 325 Location: West Texas

The 5' distance is to reduce interference from muzzle blast.( i.e. 5' from the center point between the two screens, at least that was the point of measurement on a recent thread at SGW.)
If you are testing subsonic loads you should be able to get closer and I have.

Consistency is achieved by taking extreme care in making every shell exactly the same. There are so many variables in shotshell reloading it makes consistency a time consuming project and not worth the effort for most of us.

I use mine mostly just to test my extrapolated loads. Since 16 gauge is not well documented for different combinations of loads I take two or three published loads and extrapolate a lower velocity for clays and recoil reduction. The chrony confirmed the extrapolated velocity if not the pressure.

Jeff, et al,

I actually used 3 yards with my PACT chronograph. At the time, I thought it was the standard used by US shotshell manufacturers, but of course I was wrong, as it was pointed out on another thread here -- it's 3 feet, not 3 yards. I think I got my notions from something in Ed Lowry's "Shotshell Ballistics for Windows" program for external ballistic's, and I got it wrong. http://randywakeman.com/EdLowryOnShotshellBallistics.htm I have not chronographed anything for a while, so haven't tried 3 feet since someone "wised me up". Neither have I used Lowry's ballistic S/W lately because I have changed computers and haven't re-installed it! I'll have to dig out the PACT manual and see what they recommend.

Sometime soon I will compare results with similar set-ups with my friend's ProChrono. I wonder how that will all work out, as the ProChrono has about 1 foot spacing between the screens, and the PACT has at least 2 foot spacing. I think any spacing of screen-to-screen, and screens-to-gun works for comparative testing of loads, but I wanted to compare with what I thought were industry standards -- and I guess I got those wrong. I also heard the velocities posted by most European shotshell manufacturers were somehow extrapolated back to the muzzle, leaving them a little short on velocity compared to the US method (I don't know if this is fact, fiction, or insignificant), and I wanted to compare those shells against US shells with similar posted "muzzle velocities".

I definitely understand the selection of a spacing that avoids detection of the shock wave/muzzle blast. I have had very consistent and sensible readings using 3 yard spacing to the first screen. They seem to agree with US shotshell manufacturers' published velocities fairly closely.

OK -- I dug out my manual. I have a CED Millenium chronograph, not a PACT -- more brain fade?? Anyway, my CED manual says allow 7 to 10 feet spacing from muzzle to the tripod on which the bar that holds the screens is mounted -- which means to the center of the two screens, as I take it. The screens are 2 feet apart. Then it refers me to a section on shotguns and bows I obviously never read before that says for shotguns, the first screen should be 3 to not greater than 4 feet from the muzzle of the gun, which means the center of the screens is 4 to 5 feet from the muzzle. I guess this agrees with what Dave and Jeff and others are using, more or less. Good to know. Sensing technology seems to be about the same on all these units (shadow passing), so it shouldn't be a surprise, I guess. Incidentally, the on-line info from PACT for their systems says "screens set 5 to 10 feet downrange", by the way, and cautions about muzzle blast, same as the others of course.

Went through my loading logs and it looks like the last time I used my chronograph was October 2009, testing some Sherman Bell 10 gauge loads and my own 7/8 ounce 24 gauge loads. Been a while -- need to blow the dust off this thing and use it some more!

Cheers!

Well the metal one must have run away,

But when I looked in the box the plastic shield was there Embarassed

You will notice the hole drilled into the shield for the on/off switch in the on
position

Yellow tape holds two sheet of plastic together

The plastic strays replace the metal shade uprights, and do not hurt the Chrony, if the are impacted by ejecta Smile

Or for a metal one use a hinge Smile