Comparing personal chrono with site chrono.

[Stevo4345]

After seeing a massive difference last week between what my Acetech 6000 chrono was telling me (340 on .2’s) and what the site chrono said (270 on .2’s) I decided to take mine down to chrono testing for a side by side comparison. 

Today the site chrono’d at 343, mine at 340. The only thing that I can think is that last week it was still set on a different weight or they misread a previous rifles result.

Anyway, good to know I’m not too far off the ‘official’ chrono as the tinkering continues.

 

[Druid799]

To be honest bud I’d trust my own chrono over most site chrono’s any day !

You turn up at the chrono station on a gameday they test your gun and once everyone’s been through what happens too it then ? More than likely the spotty gimboyd running the station slings it in a cupboard or junk box till the next gameday !?‍

Where as your own personal one lives in its box safe and sound until you need it .

Unfortunately that’s of no fecking use to you as on gameday they use there abused to shit chrono and rely on that one and there’s rock all you can do about it ! ?

 

[DopeYourScope]

I see it all the time, went to a site the other week and apparently my MWS was shooting way hot on 0.28s (340fps/1.5J) which was very very surprising and then I tried 0.2s as I wondered if my ammo was off and it was shooting at 360fps/1.2J, now that's some mega joule creep. I was told to be mindful that it's a bit lively and use only 0.2s, at a woodland site ?  I then used my MWS at another game last week and it was shooting perfectly at 290fps/1.1J on 0.28s like it should... Couple of my friends had the same issue but it nearly lead to me being unable to use that rifle, all because their chrono is way out of calibration.

It should be mandatory as part of their insurance that their chrono's are calibrated correctly however as far as I'm aware there aren't companies which provide such a service (dragons den for someone reading this).

 

[Rogerborg]

How would you calibrate a chronograph?

 

[DopeYourScope]

How would you calibrate a chronograph?

That was my point, you would need to design and manufacture an item which could fire a projectile consistently to within a 1% variance, which is why I offered the business idea for someone to run with.

 

[E21A]

I see it all the time, went to a site the other week and apparently my MWS was shooting way hot on 0.28s (340fps/1.5J) which was very very surprising and then I tried 0.2s as I wondered if my ammo was off and it was shooting at 360fps/1.2J, now that's some mega joule creep. I was told to be mindful that it's a bit lively and use only 0.2s, at a woodland site ?  I then used my MWS at another game last week and it was shooting perfectly at 290fps/1.1J on 0.28s like it should... Couple of my friends had the same issue but it nearly lead to me being unable to use that rifle, all because their chrono is way out of calibration.

It should be mandatory as part of their insurance that their chrono's are calibrated correctly however as far as I'm aware there aren't companies which provide such a service (dragons den for someone reading this).

What was the temperature difference between the 2 days? 

 

[DopeYourScope]

What was the temperature difference between the 2 days? 

It was maybe 16/17 degrees at the woodland site and I was indoors last week so around 22 degrees, and the other week has been the only time when it's been anywhere near being 'a hot gun'. I know why you've asked but it was nowhere near hot enough to make me even factor in temperature for my chrono results.

 

[Adolf Hamster]

Setting to a different weight shouldnt affect the output number, just the calculated joule figure. Although if i had a penny for every "thats a bit low" comment when i'm running the heavies even when the joule reading is spot on.

I'd agree with druid on this one most sites chrono's are kinda spotty, plenty of battle scars from getting nuprol bb's blasted into the side of the tube.

As for calibration i'd rather we figure out something else, i do wonder if there might be use for the old school chrono'ing they used to use for real steel that used a pendulum that you'd shoot and use the momentum as a method of calculating impact energy (and in their case velocity based on a known bullet mass) would save a lot of headaches if you could just shoot it and get a joule figure spat out. Of course that's one for dragons den.

 

[Rogerborg]

That was my point, you would need to design and manufacture an item which could fire a projectile consistently to within a 1% variance, which is why I offered the business idea for someone to run with.

How would you calibrate the projectile?

 

[DopeYourScope]

How would you calibrate the projectile?

This is where the issue lies ?

 

[ImTriggerHappy]

Simple answer is all sites should be using decent chronos not hobbyist ones like acetech and xcortech.

The skan chronos that I like can be sent back for testing and re-certification and the new models have a self check.

The cheap ones are ok for getting a rough estimate at home but not reliable enough for checking paying customers.

 

[jcheeseright]

I've had this a couple of times with shitty chronos being operated by idiots who have no idea how they work.  Went to a site near bristol a couple of years back with a stock TM that was somehow doing 550fps with .25g BBs.... or was it?  Of course it wasn't, the marshal had the chrono set up with the sun shining down the 'tube' which confused the shit out of the sensors and made it do all sorts of crazy shit.  Turned the chrono 90 degrees so the tube was in the shade and we were back to a normal 250fps. 

 

[Druid799]

Dragon valley had a similar sort of thing happen a good few yrs ago , a honking big storm was brewing there’d been a couple of big thunder claps and as some chap was chrono’ing there was a big ass flash of lightning just as he fired and that FPS reading was apparently an impressive number !??

 

[Tackle]

Simple answer is all sites should be using decent chronos not hobbyist ones like acetech and xcortech.

The skan chronos that I like can be sent back for testing and re-certification and the new models have a self check.

The cheap ones are ok for getting a rough estimate at home but not reliable enough for checking paying customers.

My chrono's an old one, made by coke cola, but I'm saving up for a new one, prob Red Bull ?

View attachment 48312

 

[Rogerborg]

My chrono's an old one, made by coke cola, but I'm saving up for a new one, prob Red Bull ?

View attachment 48312

You are this article's author, and I claim my 5 (foot) Pounds: https://www.instructables.com/id/Poor-mans-airsoft-chrono/

 

[Stevo4345]

Ha, I have seen that method, too scared to try it for the short range ricochets scarring my handsome mush!

 

[CrackCommandoUnit1972]

I bought a cheapo E9800-X from the darkest regions of the internet and surprisingly it was pretty much recording the same as the chrono at the last site I played at.

Which was a relief as I have an M4 shooting at 340-345fps on my chrono and I was worried that the site chrono would record it as being too hot, but no, it passed and I had a great day pew pewing with it.

 

[Rogerborg]

I bought a cheapo E9800-X from the darkest regions of the internet and surprisingly it was pretty much recording the same as the chrono at the last site I played at.

Which was a relief as I have an M4 shooting at 340-345fps on my chrono and I was worried that the site chrono would record it as being too hot, but no, it passed and I had a great day pew pewing with it.

I don't actually care what my AEGs are really shooting at with 0.2g BBs, just so long as they don't go over 350fps on the site chrono.

I did care a little bit that my boltie chronoed at 600fps / 3.33J with a "500fps" spring in it, because that made it an unlicensed (for Scotlandshire purposes) air rifle.

Now that it's clipped to under 2.5J, I only care about the site chrono again.

If buying a £30 E9800-X gets me there, then...

 

[Druid799]

Which was a relief as I have an M4 shooting at 340-345fps on my chrono and I was worried that the site chrono would record it as being too hot, but no, it passed and I had a great day pew pewing with it.

And this children is the exact reason I DON’T try to get my guns firing at 349.5555555FPS like so many do . You have to leave your self a very good margin of error for chrono’ing Or your gun ‘firing at a  consistent 349fps’ is going to turn around one day bite you on the ass because of some crappy site chrono and you won’t be able to use it ! ?‍

 

[clumpyedge]

And this children is the exact reason I DON’T try to get my guns firing at 349.5555555FPS like so many do . You have to leave your self a very good margin of error for chrono’ing Or your gun ‘firing at a  consistent 349fps’ is going to turn around one day bite you on the ass because of some crappy site chrono and you won’t be able to use it ! ?‍

Grinds my gears when people come to the chrono and start harping on about their gun being 349.9 and how amazing it is because its right on the limit. BULLSHIT the site limits are NOT a target they are just a limit, plenty of guns that are way under that can shoot a hell of a lot better which is proven the higher powered gun cant hit the side of a barn door later with their close to the limit RIFS. Power is only one of many factors that make a gun shoot well, try telling matey who brings his 5 different guns to the chrono that he's worked on himself... one doesn't even feed, one doesn't get more than 3ft and two shoot every which way but straight.