about accuracy

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mrfoo
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Fri Jan 01, 2021 4:59 am

PracticallySane wrote:
Thu Dec 31, 2020 12:51 pm
Doesn't it? 🙂
No, it doesn't. It indicates an inability to correctly express oneself. Text is perfectly capable of conveying emotion and intent; there's a whole section of the arts dedicated to it. It's been around for a while, you might have heard of it. It's called "literature". You'll perhaps also notice that there are non-native english speakers on this very forum who are quite capable of expressing themselves without causing offence or having to resort to smilies.

Saying something flat out rude, and then saying "no disrespect intended", with a fucking yellow atrocity tacked on the end screams out, to me at least (although I am a cantankerous old cunt), that every disrespect implied in the original post was, actually, intended.

If there was, actually, no offence intended, the correct approach would have been:
  • Read your post before posting, think "hrm, that's a bit rude, I wouldn't like it if someone said that to me" and edit post as appropriate.
  • OK, you've missed that, it's hit the interwebs. Bugger, that's rude, I didn't mean it to come across like that! There's an "edit post" button with which you can change what you've just posted (I'm not overly keen on rewriting posts, I'll usually only use that to add text, fix grammar, or remove stuff using the strikeout tag). Or copy everything and delete the post entirely, redo it from scratch. Both of these only really work if done quickly.
  • Hrm, the reasonable edit window has expired, and the person has probably taken offence. The solution to this is simple - you apologise (and either take down the offending post or edit it). No smilies, no weasel words.
As for the rest, it's how many angels can dance on the head of a pin. Ask yourself if the magnus effect works in a vacuum, though.
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Fri Jan 01, 2021 9:32 am

The magnus effect, joins in airsoft to oppose the normal parabola made by the plastic ball. We are using a "defect" to compensate for another "defect" to the contrary.
If the effecyo magnus cannot be used in contrast, the ball will definitely go off target.
I shoot 1/4 "steel bb's with a smooth bore barrel. If the barrel has any imperfections, and the ball acquires rotation it is a damn disaster. The accuracy is good, when the ball is adjusted as much as possible and it has almost no rotation.
In other words, a person with perfect eyesight does not need glasses. If you have a vision problem, (the defect you want to correct),, oppose the opposite defect, (the characteristics of the lens), and solve the problem. Otherwise, if you put on glasses without calculating what the eye needs, you will see less than a blind mole.
It appears that the lead balls that fit tightly into the grooves deform when pressed by the propellant gases, and when deformed, the magnus effect has little value, because it only applies to fairly perfect spheres. I think this is the reason why the "non-deformable" bb's, such as those made of steel or plastic, which the airsoft gun cannot deform, are more influenced by the magnus effect, than the lead that comes out of the hemispherical barrel.
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bravootome
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Fri Jan 01, 2021 10:28 am

PracticallySane wrote:
Thu Dec 31, 2020 7:30 am
To amend my previous statement.

I looked into airsoft and how the magnus effect pertains to accuracy.

Airsoft guns use a "hop-up" to impart back spin to the projectile. This gives it a desirable lift increasing range and accuracy.

However if you try to impart rotational energy the way rifling does to a bullet you will never hit the same space twice.

My apologies.
its a airsoft that shoots over 1000 fps( if i want it to ), so a hopup will just not work , but why same gun had worked perfectly ? i replaced that barrel, after i put a metal bolt into it and broke it, with another one same brand , than another one and one ....so thats the only thing i changed + other beneficial mod like zero hammer bounce, stainless airtank, better scope ....etc
but what i notice is that the bb had no drop before from 10 m to 60 m, now i see it dropping .....
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Fri Jan 01, 2021 12:14 pm

I am hesitant to chime in, seems i have a dissenting opinion.

Thank you hectmarr, language is not something I study, and your post even in translation is clear and concise. I guess I could not explain properly.

As hectmarr stated any imperfection in the barrel will affect performance.

Personally I thing you would have a huge benefit from heavier ammo.

I found this article maybe it will help.
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Last edited by PracticallySane on Fri Jan 01, 2021 12:35 pm, edited 1 time in total.
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Fri Jan 01, 2021 12:27 pm

It is logical what it says. A 1/4 "steel pellet weighs almost exactly 1 gram. The mass of the ammunition should influence its rotational speed as it exits the barrel intentionally or unintentionally. The heavier, the more resistance to rotating at high speed. Unfortunately, I only have steel bb's that I can buy, and I use them because they are reusable, you can collect them in a box that stops this ammunition and reuse it many times. I can't with lead because they deform just by shooting them I have tested this by impacting them on soft mub surfaces and pulling them from a distance. At the first shot with a smooth-bore barrel they deform, and if it is a rifled barrel, worse, the grooves remain and tend to oval ...
For the rest, feel free to comment. I don't see anyone's lack of respect for anyone here. I'm not going to say anything else about this "pull" because surely the "game" will be between three, instead of two. I apologize in advance if my comment offends or makes someone uncomfortable, sorry, sorry, sorry ... :D :) :D :) :D :) :) :) :) :) :) :) :) :) :)
This afternoon I will read the article that I need to understand about this, even if I do not have a doctorate in atomic physics! :twisted:
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Sat Jan 02, 2021 10:26 am

i' ve kind off got sick about this, only a lothar walther barrel will make me do some work on air rifles form now on, and how its no way to buy one ill just pause this . ive allready spent 200 euro with this idea , a proper pcp costs about 300 e...so.....if it is any one here who knows an airsoft can shoot like a pelletgun, let me know
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bravootome
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Sat Jan 02, 2021 10:28 am

PracticallySane wrote:
Fri Jan 01, 2021 12:14 pm
I am hesitant to chime in, seems i have a dissenting opinion.

Thank you hectmarr, language is not something I study, and your post even in translation is clear and concise. I guess I could not explain properly.

As hectmarr stated any imperfection in the barrel will affect performance.

Personally I thing you would have a huge benefit from heavier ammo.

I found this article maybe it will help.
there is no heavier 6 mm ammo than 0.50 g except steel bbs that will destroy the barrel, so......
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Sat Jan 02, 2021 10:37 am

hectmarr wrote:
Fri Jan 01, 2021 12:27 pm
It is logical what it says. A 1/4 "steel pellet weighs almost exactly 1 gram. The mass of the ammunition should influence its rotational speed as it exits the barrel intentionally or unintentionally. The heavier, the more resistance to rotating at high speed. Unfortunately, I only have steel bb's that I can buy, and I use them because they are reusable, you can collect them in a box that stops this ammunition and reuse it many times. I can't with lead because they deform just by shooting them I have tested this by impacting them on soft mub surfaces and pulling them from a distance. At the first shot with a smooth-bore barrel they deform, and if it is a rifled barrel, worse, the grooves remain and tend to oval ...
For the rest, feel free to comment. I don't see anyone's lack of respect for anyone here. I'm not going to say anything else about this "pull" because surely the "game" will be between three, instead of two. I apologize in advance if my comment offends or makes someone uncomfortable, sorry, sorry, sorry ... :D :) :D :) :D :) :) :) :) :) :) :) :) :) :)
This afternoon I will read the article that I need to understand about this, even if I do not have a doctorate in atomic physics! :twisted:
even steel bbs deform at impact with a piece of paper ( but only on high fps ) , tested the long time ago.....if you look closely you will see a flat part on the bb... so plastic is better ... ive just put 30.000 bbs trough the gun ...past yer ..
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Sat Jan 02, 2021 11:32 am

YES, it is exactly like that, unless you shoot on a soup can, or something not very hard. The bb's that I use weigh 1 gram. The light weight of the 6 mm plastic bb's is the light weight, very light for my taste, although I also use those.
When I go to shoot in the backyard of my house, I do it about 80 or 100 times ... :) I only use 20 bb's of steel and from time to time, I lose 1 or 2.
The other problem is that in some of the bb's charging systems that I have tried, the plastic ones crumble and split ... For example, in the system activated by the combustion chamber gases themselves. The needle mistreats them, and they become imperfect and everything gets stuck ... with steel it doesn't happen.
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Sat Jan 02, 2021 12:24 pm

hectmarr wrote:
Sat Jan 02, 2021 11:32 am
YES, it is exactly like that, unless you shoot on a soup can, or something not very hard. The bb's that I use weigh 1 gram. The light weight of the 6 mm plastic bb's is the light weight, very light for my taste, although I also use those.
When I go to shoot in the backyard of my house, I do it about 80 or 100 times ... :) I only use 20 bb's of steel and from time to time, I lose 1 or 2.
The other problem is that in some of the bb's charging systems that I have tried, the plastic ones crumble and split ... For example, in the system activated by the combustion chamber gases themselves. The needle mistreats them, and they become imperfect and everything gets stuck ... with steel it doesn't happen.
it is a big problem if a bb is even scratched while loading, but cracked even bigger , i dont use steel bbs anymore as they will mark the barrel , but when i used the i got to hit a mach box ( @ 5x 3 cm) by 40 m every time... so why do they not make lead 6 mm bbs ? maybe this is a bussines ideea !
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Sat Jan 02, 2021 12:33 pm

bravootome wrote:
Sat Jan 02, 2021 12:24 pm
hectmarr wrote:
Sat Jan 02, 2021 11:32 am
YES, it is exactly like that, unless you shoot on a soup can, or something not very hard. The bb's that I use weigh 1 gram. The light weight of the 6 mm plastic bb's is the light weight, very light for my taste, although I also use those.
When I go to shoot in the backyard of my house, I do it about 80 or 100 times ... :) I only use 20 bb's of steel and from time to time, I lose 1 or 2.
The other problem is that in some of the bb's charging systems that I have tried, the plastic ones crumble and split ... For example, in the system activated by the combustion chamber gases themselves. The needle mistreats them, and they become imperfect and everything gets stuck ... with steel it doesn't happen.
it is a big problem if a bb is even scratched while loading, but cracked even bigger , i dont use steel bbs anymore as they will mark the barrel , but when i used the i got to hit a mach box ( @ 5x 3 cm) by 40 m every time... so why do they not make lead 6 mm bbs ? maybe this is a bussines ideea ! about the weight of 0.5 grams plastic bbs, i use those as there are lead pellets of same weight for pelletguns so they should do the job, and they does it as they destroy anything i use as target, as for example a beer glass bottle is pulverised( ??) by it from 30 m or so
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Sat Jan 02, 2021 3:57 pm

bravootome wrote:
Sat Jan 02, 2021 12:33 pm
bravootome wrote:
Sat Jan 02, 2021 12:24 pm
hectmarr wrote:
Sat Jan 02, 2021 11:32 am
YES, it is exactly like that, unless you shoot on a soup can, or something not very hard. The bb's that I use weigh 1 gram. The light weight of the 6 mm plastic bb's is the light weight, very light for my taste, although I also use those.
When I go to shoot in the backyard of my house, I do it about 80 or 100 times ... :) I only use 20 bb's of steel and from time to time, I lose 1 or 2.
The other problem is that in some of the bb's charging systems that I have tried, the plastic ones crumble and split ... For example, in the system activated by the combustion chamber gases themselves. The needle mistreats them, and they become imperfect and everything gets stuck ... with steel it doesn't happen.
it is a big problem if a bb is even scratched while loading, but cracked even bigger , i dont use steel bbs anymore as they will mark the barrel , but when i used the i got to hit a mach box ( @ 5x 3 cm) by 40 m every time... so why do they not make lead 6 mm bbs ? maybe this is a bussines ideea ! about the weight of 0.5 grams plastic bbs, i use those as there are lead pellets of same weight for pelletguns so they should do the job, and they does it as they destroy anything i use as target, as for example a beer glass bottle is pulverised( ??) by it from 30 m or so
The heaviest 6 mm that I get in my city are 0.25 grams.
Lead, to that extent, does not exist here, not less than 6.35 mm spherical lead ...
The 6.35 carbon steel ones, I use to pierce a 0.6mm steel plate with my autonomous hybrid at about 12 meters. They have tremendous piercing power, and also a lot of durability, whether you shoot to mark the target, over many layers of cardboard, or a phone book. After you finish shooting, you pick them up, clean them, and lubricate them before storing them in an airtight box.
I imagine they are not manufactured for commercial reasons, as you say.
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Sun Jan 03, 2021 7:35 am

well it looks like when i clean the barrel after every shoot, it shoot hole to hole by 22 m ( where my target is set ) . So i can see small black particles inside the barrel when accuracy goes crazy. i am in process of cleaning again the airtank , it looks like the particles are from the welding....
is there any way i can weld a new tank without the welding "lava" finds its way inside ? ( i do not own a tig welding machine, only stick , and no way to cut screw (?) into the pipe)- just welding
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Sun Jan 03, 2021 8:01 am

Purge weld (Tig) is the only way I know of, can you purge with stick ? probably too much heat, that's why you get the burn through.
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Sun Jan 03, 2021 10:48 am

Tig welding uses inert gasses instead of slag "lava" to shield the weld from atmosphere.

Your cheapest option would be a braze, they are easy to preform and can hold alot of pressure when properly executed. All you need is a propane torch in most cases.

Look into the brazing process on youtube, there is alot of content on the matter.
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