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Discussion Starter · #1 ·
Hey guys. I have a F-1 Chrony and I shot several rounds of 175gn HPBT with my .308. I had the chrony set out about 10 feet from the muzzle. 10 rounds gave me an average of 2664. I went out and shot at some soda bottles at 500 yards, did the math on my ballistic software and shot. Slightly high. My friend used it to work up some loads and put the chrony 2 feet from the muzzle. Loaded up some 150 gn .308 bullets got an average X fps. He went with a different ballistic program and shot in the same place i did and slightly high. My 22-250 was showing only 3100 fps (pretty slow for a 250). IS my chrony showing slower than it should? I dont know anyone else who has a chrony to check against. Anyone ever experience this problem?
 

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Depending on the ammo you used and your barrel length (i.e. Federal 175 gr Match with 26â€
 

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Discussion Starter · #4 ·
It was sunny as it always is here in southeast New Mexico and I didnt have that plastic deal that goes over the top of the eyes installed. I bet that is the reason.
 

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I decided this weekend to test my F1 chrony against the Oehler unit that my range owner uses. Set mine up as close as possible right in front of his, maybe 1ft away. Every single shot I took mine was reading 21-22fps faster than his.

If you go with the saying you pay for what you get, then I assume his to be the correct one.
 

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I went through similar questions over the last few months when multiple guns were producing higher than expected MV on my F1 Chrony, and then shooting lower than the predictable drop, Here I thought owning my own chrono would improve the predictablility of my drop data......not so much. It helps eliminate some guess work, but it has it's own variability. F1 chrony has a +/- toleance of 1%, which at 3000 MV could be a 59 ft/sec variance and still be in spec, let alone what the ammo is actually doing.

After contacting "Shooting Chrony" (google them for contact info), I returned mine back to the factory for calibration. Cost me freight both ways and $20. It was returned to me with a note that it had been tested and found to within tolerance. Upon it's return, I noticed that all of my ammo had suddenly slowed down. My 308 168 gr HPBT went from an average of 2713 to 2630. Coincidentally, federal says is should be 2600. I've read internet feedback that the F1 Chrony's make better ashtrays than chronographs, and I would say based on my experieince that the investment is not necessary. Start with box rated speeds on your drop program, then verify everything in the field and adjust the model until it matches what you are experiencing. I have found the outcome of that process to increase your ability to pre-call the drop, over and above using chronographed MV's and relying on a program.
 

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cwright said:
I went through similar questions over the last few months when multiple guns were producing higher than expected MV on my F1 Chrony, and then shooting lower than the predictable drop, Here I thought owning my own chrono would improve the predictablility of my drop data......not so much. It helps eliminate some guess work, but it has it's own variability. F1 chrony has a +/- toleance of 1%, which at 3000 MV could be a 59 ft/sec variance and still be in spec, let alone what the ammo is actually doing.

After contacting "Shooting Chrony" (google them for contact info), I returned mine back to the factory for calibration. Cost me freight both ways and $20. It was returned to me with a note that it had been tested and found to within tolerance. Upon it's return, I noticed that all of my ammo had suddenly slowed down. My 308 168 gr HPBT went from an average of 2713 to 2630. Coincidentally, federal says is should be 2600. I've read internet feedback that the F1 Chrony's make better ashtrays than chronographs, and I would say based on my experieince that the investment is not necessary. Start with box rated speeds on your drop program, then verify everything in the field and adjust the model until it matches what you are experiencing. I have found the outcome of that process to increase your ability to pre-call the drop, over and above using chronographed MV's and relying on a program.
Are you sure its 1%? I thought the paperwork with mine said +-1fps
 

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Chronographs are very helpful when handloading and you don't have factory info or a firearm rig not covered in the manuals.

There is another reason for using one and that is as a pressure warning tool. For example let's say a load should be giving you 2700fps and you find that you're getting 2900fps, then something is wrong somewhere! You may have a tight chamber, bore or something else but you need to find out what it is.

RE: Chrony's I've seen too many used by knowledgeable people to believe they're that bad. I've also found that on the 'Net there is somebody willing to bad-mouth anything. Are there better ones? Probably. More affordable for the average shooter. Well maybe. CED's come to mind. But I've compared mine to the CED at one of my ranges and they were very close.
 

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RE: Chrony's I've seen too many used by knowledgeable people to believe they're that bad. I've also found that on the 'Net there is somebody willing to bad-mouth anything. Are there better ones? Probably. More affordable for the average shooter. Well maybe. CED's come to mind. But I've compared mine to the CED at one of my ranges and they were very close
I've owned Shooting Chronys, Pro Chronys and CEDs. There isn't a lot of difference in accuracy. I like the extras that CED offers, and it's cheaper to replace a sensor on a CED than a whole Chrony - the usual thing that happens when you accidentally shoot one. When you load and ladder test for thousands of rounds, it's gonna happen more than once.

Jeff
 

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And really how do you know whose chrono to trust?

I guess you would hope if youre one of the guys that paid $3-500 for one youd expect it to be accurate, but whos to say it is. Consistency and accuracy are the most important things, either one can be more important depending on what you are using it for.

I found mine to be EXACTLY 21-22fps faster than the Oehler unit I compared it to, although it was also about a foot in front of it so that could add a few fps.
 

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Something funny happend the other day. Thats why i'm coming back to this post.

We build two rifles both on surg. actions in 308 both had 22in barrels from kreiger.

Barrels looked outstanding with bore scope.

We use FGM to break in the throats of the guns witch is really a good way to put we like shooting. And to test for groups.

Well one rifle was running average 33fps over box vel. and the other was running 9fps slower than box vel.

All shot threw the same chrony. All barrels were measured at 9ft 6in

So it goes to show that every barrel even back to back barrels from kreiger shoot different and vel on boxs are a good guide line to go off of.

Now my 300win mag that got 1466 round threw it as of last sat... still shoots great and still does not even come close to FGM box specs.

So with all that said a Chrony is as good as its going to be. Yes there cheap and theres costly. i've never seen two rifles or two chronys shoot the same.

So when working loads and using a chrony take the book specs on vel and the chronys and see there they fall in average. Then if your looking for range data it will get you close, for drops.

Thats only my 1/2 cents worth

Tom
 

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Discussion Starter · #13 ·
After I started shooting to find a load my gun likes, I decided to wave the chrony until I found a sub .5 MOA load. Then I would chrony it. I came up with a FPS to start with. I would then shoot a know distance and adjust my scope based off my ballistic calculator until I was shooting level. (600 yds gave me 15.5 MOA). Then shoot another know distance i.e. 300 yards and adjust my scope until the elevation was perfect. Then I would change my FPS in my ballistic calculator until these two lined up. Turned out my chrony was about 70 FPS faster than actual. This worked pretty good for me.
 
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