HPA and the future

Feedback and debriefings from Berget 16
L4gi
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Re: HPA and the future

Post by L4gi » 05 Jul 2018, 16:26

Majk wrote:
05 Jul 2018, 13:24
L4gi wrote:
05 Jul 2018, 12:23
Simplest and easiest way to chrono would be using ingame BB and measuring joules from the end of the barrel. We've been doing that in Finland for a really long time already, and it seems to be quite a well working solution.
Yes, this has many benefits and I can easily see that metod optimal for smaller events and theres adjustments possible for larger too. The only downside... this would make it easier to cheat, im not sure if i wanna do that, or work around that. The other simple option would be to chrono with a heavy bullet for example 0.3, but then again we have many inaccurate readings (like the current system, but in a better way). The third option would be a more complicated and slower system like VSAF for an example. Its a hard choice when you have to sacrifice something. I want to explore IF we can come up with a system with lesser downsides before we choose among the ones we know.
I'd be glad to consult on this matter. ;)
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05 Jul 2018, 15:28
I must admit, I was surprised how few people I saw wearing enclosed eye protection (i.e. goggles not shooting glasses), or mouth protection.
99% of shooting glasses provide enough cover to block the BB from entering near the eye. For everything else theres personal insurance. :D
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Re: HPA and the future

Post by BF-28 » 06 Jul 2018, 22:47

Joule creep is the biggest problem. My P* M27 is 301fps @0.20 and 348 fps(equvalent) with 0.30's.

This year my m249 chronoed at 120ms with 0.20 and 138(equvalent) with 0.30 longbows. With a decent 22rps.

None of my regs were ziptied (i ziptied them myself..) or Notting. Chronoing with joules with 0.20 is useless. I understand that hpa joule chronoing is a problem, but chroning with 0.30s for full auto and 0.36 for semi should solve the problem.


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Re: HPA and the future

Post by Majk » 07 Jul 2018, 03:42

BF-28 wrote:
06 Jul 2018, 22:47
Joule creep is the biggest problem. My P* M27 is 301fps @0.20 and 348 fps(equvalent) with 0.30's.

This year my m249 chronoed at 120ms with 0.20 and 138(equvalent) with 0.30 longbows. With a decent 22rps.

None of my regs were ziptied (i ziptied them myself..) or Notting. Chronoing with joules with 0.20 is useless. I understand that hpa joule chronoing is a problem, but chroning with 0.30s for full auto and 0.36 for semi should solve the problem.


My drunk 0.02$
Yes, Joule creep is a problem.
Your readings seems very high though, from 0,84J to 1,69J... (100% more energy!) this looks way off.
Ive done simular tests with several HPAs and I rarely get more then 30% Joulecreep when i go from 0.2 to 0.3
Last edited by Majk on 07 Jul 2018, 14:54, edited 1 time in total.
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Re: HPA and the future

Post by MiqaFox » 07 Jul 2018, 11:07

Majk, his readings are probably not off. I've seen similar ones before. It depends on a lot of factors, like barrel length, air pressure, hop-up setting, bore diameter.

The serious thing here is that if you tweak these parameters, you can have an even larger difference in the readings and it would still be classified as field legal at Berget with the current rules.
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Re: HPA and the future

Post by L4gi » 07 Jul 2018, 11:33

We've been using 1.2 joules for CQB, 1.7 joules for full auto rifles, 2 or 2.25 joules for machineguns and semisnipers and 3-3.5 joules for bolt action rifles at big games in Finland.

Every gun gets chroned by the players ingame bb and is measured from the end of the barrel. Quite an easy system, and its very easy to do in the field chronos.
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Re: HPA and the future

Post by Majk » 07 Jul 2018, 13:28

Joule creep is the biggest problem. My P* M27 is 301fps @0.20 and 348 fps(equvalent) with 0.30's.
MiqaFox wrote:
07 Jul 2018, 11:07
Majk, his readings are probably not off. I've seen similar ones before. It depends on a lot of factors, like barrel length, air pressure, hop-up setting, bore diameter.

The serious thing here is that if you tweak these parameters, you can have an even larger difference in the readings and it would still be classified as field legal at Berget with the current rules.
Well, if he measures at end of barrel the fps should go down and the Joule should go up with heavier BBs, it's the same size and geometric form, the only variable is weight. I seriously doubt he can break the laws of Physics...

I assume he has the same configuration of the gun otherwise its not a valid test at all.

A qualified guess, if he has done his test right and only changed the weight of the BBs, he might have mixed up the fps readings... If thats the case I get 13% Joulecreep which sounds quite reasonable.
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Re: HPA and the future

Post by Snygg » 08 Jul 2018, 13:22

[/quote]

When I chrono my HPA i asked about the tournament lock. the answer i got back was that they wrote down my pressure & M/S and my booking no.
thats all. got a bit confused also.

when it comes to the choro there was a A-HA experience before I left home I had adjust the gun to ~137 m/s (112m/s with 0.30) and at BE i got ~126m/s with their BBs.... I decided to use 15m because I didn't trust their chrono.

So BE really need to change their chrono rules.

/N
[/quote]

Nobody even bothered to check if my HPA 249 had a tournament lock, nor noted the pressure or my ticket id. Then again, it chronoed at 89 m/s with .2's, but still.

I hope the merc player responsible for shooting up the tan Pajeros windows confesses and offers to pay for the damage caused. Or that the other merc players who played with that guy gives his name up.

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Re: HPA and the future

Post by TerrenceAnth » 08 Jul 2018, 16:01

I am a hpa user as are most of my team. I think the main issue is not the hpa system but the people using it. Here in Ireland we are limited across the country to 328 fps nothing over. So when we come to Sweden the ease of just turning it up to 400 fps is a real thrill for us to be firing harder and future.
I think they key difference between my team is because we know our HPA's are turned up and we know our limit at home hurts like hell when hit up close and personal. We are constantly paranoid we are too close to people or firing 2-3 shots just to be sure we dont over kill anybody.

Common sense is all it takes to have a safe and fun game... Unfortunately its not too common :P
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Re: HPA and the future

Post by Panzergraf » 08 Jul 2018, 22:06

Majk wrote:
07 Jul 2018, 03:42
BF-28 wrote:
06 Jul 2018, 22:47
Joule creep is the biggest problem. My P* M27 is 301fps @0.20 and 348 fps(equvalent) with 0.30's.

This year my m249 chronoed at 120ms with 0.20 and 138(equvalent) with 0.30 longbows. With a decent 22rps.

None of my regs were ziptied (i ziptied them myself..) or Notting. Chronoing with joules with 0.20 is useless. I understand that hpa joule chronoing is a problem, but chroning with 0.30s for full auto and 0.36 for semi should solve the problem.


My drunk 0.02$
Yes, Joule creep is a problem.
Your readings seems very high though, from 0,84J to 1,69J... (100% more energy!) this looks way off.
Ive done simular tests with several HPAs and I rarely get more then 30% Joulecreep when i go from 0.2 to 0.3
If you want to see extreme joule creep, check out GBBR's (gas-in-mag, not HPA) and gas powered bolt actions. Even GBB pistols have a lot of joule creep because of how the liquid propellant expands when it enters a gas state.
More than most HPA rifles, as the HPA is a gas to begin with, even under pressure.
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Re: HPA and the future

Post by Dutchman » 17 Jul 2018, 10:26

Personally I switched from an AR to an M700 during the game and went to the Berget crew to have my M700 chronoed. Since the gun has a 640mm barrel and is HPA-tapped, the joule creep is quite high... So what to do? I sent the regulator so it produced 149 m/s and treated it as a 180-200 m/s gun.

We all have a personal responisibility. We are not at Berget to hurt other people!

I would propose to put in a 'latrine duty' system: if some1 endangers another have him/her clean 1 row of toilets as a first punishment.

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Re: HPA and the future

Post by Verage » 17 Jul 2018, 15:15

We did some testing with our team this year on joule creep.
We tested 60 rifles with 40 different kind of BBs. This on the same day.
all the data is online for people to use.

If you have any questions, just contact me.

Livestream about the data:
https://www.youtube.com/watch?v=jaSmVI-GB1U

The excel file with the data:
https://drive.google.com/open?id=14FS9G ... eUSqp5cOrw

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Re: HPA and the future

Post by Iprenen » 27 Aug 2018, 06:23

[quote=Majk post_id=77393 time=1530962920 user_id=851]
Joule creep is the biggest problem. My P* M27 is 301fps @0.20 and 348 fps(equvalent) with 0.30's.


Majk, his readings are probably not off. I've seen similar ones before. It depends on a lot of factors, like barrel length, air pressure, hop-up setting, bore diameter.

The serious thing here is that if you tweak these parameters, you can have an even larger difference in the readings and it would still be classified as field legal at Berget with the current rules.


Well, if he measures at end of barrel the fps should go down and the Joule should go up with heavier BBs, it's the same size and geometric form, the only variable is weight. I seriously doubt he can break the laws of Physics...

I assume he has the same configuration of the gun otherwise its not a valid test at all.

A qualified guess, if he has done his test right and only changed the weight of the BBs, he might have mixed up the fps readings... If thats the case I get 13% Joulecreep which sounds quite reasonable.
[/quote]

Not at all: Joule creep is about the efficency of a gun. With HPA, GBBR, bolt snipers and Semi snipers, you often have a bigger air volume being released than the air volume in the inner barrel.

This means that when you chrono a gun with extensive air volume with 0.20g bbs, the bb will have left the barrel before maximum pressure has been obtained, meaning that alot of energi goes to waste. If you then utilize .3 or 0.43, the bb stays longer in the barrel (mostly) and absorb more of the energy before leaving the barrel and as a consequence, have been joule creeped.

I agree that he can't break the laws of physics but the law of energy of a moving object does not take the acceleration of the object. Newtons first law (M*v^2) is only a point in time measurement.
Newtons second law (m/s/s) is the one introducing joule creep.

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