Former FLL Now MSP Diver
Contributor
Yeah - the "kinder, gentler" UP isn't as much fun to play with as he used to be.
Marc
Spearfishing, Broken Finger
- Thread starter Sara Smiles
- Start date
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Yeah - the "kinder, gentler" UP isn't as much fun to play with as he used to be.
Marc
Laurence Stein DDS
Medical Moderator
Uncle Pug,
You don't like ALL spearguns or only those of certain nationalities? Informed minds want to know.
The statement kinda reminds me of patients who tell me "they don't believe in root canals". Is it they don't believe that root canals can be done or is it they don't believe that root canals really exist? Perhaps, they don't believe that root canals really work or maybe they don't believe that root canals usually don't hurt. Most probably they don't believe that the tooth I told them is a gonner is going to need a root canal or else they're gonna need an extraction. Then they tell me that "They don't believe in extractions....."
Have you EVER seen a person with a spear through them on your boat or other boat? I'm not counting pictures. I suspect more people are being bitten by sharks than being shot by spearguns.
Obviously, a speargun is a dangerous device. All standard firearms rules apply to it as well. The valve on your tank is also a really dangerous device when you forget the bungee cord and it falls down and go BOOM! Didja every worry that your valve was going to explode behind your head while diving and you'd never have the chance to notice it?
Now, onto WreckWriter. The literature that used to be packaged with pneumatic guns actually listed the shaft speed and it mentioned 250 mph.
The major mechanical difference between band guns and pneumatic guns is how the spear is accelerated. Bands start with tremendous energy--probably greater than a pneumatic. As soon as they start to decrease in length, the force of acceleration decreases--to zero as the bands return to their original shape. As the shaft leaves the gun, there is NO force being applied to the spear. It's all momentum. Band guns are affected by the drag of the water on the bands so they also lose effective acceleration underwater.
Pneumatic guns are pressurized (duh!). Work is applied against a piston trapped in a barrel under pressure to cock the spear. Sort of an air spring. Loading the gun actually increases the internal pressure slightly. When you pull the trigger, the air pressure pushes the spear forward. It continues to accelerate for the entire length of the barrel. Up until the piston reaches the forward stop, the spear accelerates with little loss of force on the shaft.
The ultimate result is that a pneumatic spear is faster than a band spear assuming high pneumatic pressures vs heavy elastic bands. Deep diving affects a pneumatic gun more than an elastic gun. At 100 feet, you have 44.1 lbs/sq in less than at the surface or about 10% less than at the surface if you are pumped to 400 lbs/sq in at the surface. 355.9 lb/sq in is still quite a bit of pressure on a piston which has about 1/2 sq in area. (Yes, I have used relative pressure rather than absolute. They both start at 1 ATA)
My gun is pumped to over 500 lb/sq in.
Personally, I don't want to use radar speed detector aimed at the spear to check speed. So if you don't want to believe 250 mph I won't argue. Would you like to play catcher at, let's see, 150 mph? How about 100 mph. I'll take ANY speed you want--I just don't want to be at the receiving end. We can agree on this? Right?
BTW, one or two nice fish and a few lobster and I'm happy for the day. I can't say as much for the commercial fisherman who manage to clean out vast areas. Even anglers will boast of finding "grouper holes" and getting an unbelievable number of fish. Dolphin (fish, not flipper) fishermen commonly catch large numbers when they find a school. They leave a hooked "schoolie" in the water to attract the rest of the school. Then it's every fish for itself--until they are all caught.
Me and my gun did not wipe out the Spanish Mackerel population. About the only thing I can't do for fish supplies is catch and release--the hole makes them sink.
So Sara, keep on shooting.
Larry Stein
You don't like ALL spearguns or only those of certain nationalities? Informed minds want to know.
The statement kinda reminds me of patients who tell me "they don't believe in root canals". Is it they don't believe that root canals can be done or is it they don't believe that root canals really exist? Perhaps, they don't believe that root canals really work or maybe they don't believe that root canals usually don't hurt. Most probably they don't believe that the tooth I told them is a gonner is going to need a root canal or else they're gonna need an extraction. Then they tell me that "They don't believe in extractions....."
Have you EVER seen a person with a spear through them on your boat or other boat? I'm not counting pictures. I suspect more people are being bitten by sharks than being shot by spearguns.
Obviously, a speargun is a dangerous device. All standard firearms rules apply to it as well. The valve on your tank is also a really dangerous device when you forget the bungee cord and it falls down and go BOOM! Didja every worry that your valve was going to explode behind your head while diving and you'd never have the chance to notice it?
Now, onto WreckWriter. The literature that used to be packaged with pneumatic guns actually listed the shaft speed and it mentioned 250 mph.
The major mechanical difference between band guns and pneumatic guns is how the spear is accelerated. Bands start with tremendous energy--probably greater than a pneumatic. As soon as they start to decrease in length, the force of acceleration decreases--to zero as the bands return to their original shape. As the shaft leaves the gun, there is NO force being applied to the spear. It's all momentum. Band guns are affected by the drag of the water on the bands so they also lose effective acceleration underwater.
Pneumatic guns are pressurized (duh!). Work is applied against a piston trapped in a barrel under pressure to cock the spear. Sort of an air spring. Loading the gun actually increases the internal pressure slightly. When you pull the trigger, the air pressure pushes the spear forward. It continues to accelerate for the entire length of the barrel. Up until the piston reaches the forward stop, the spear accelerates with little loss of force on the shaft.
The ultimate result is that a pneumatic spear is faster than a band spear assuming high pneumatic pressures vs heavy elastic bands. Deep diving affects a pneumatic gun more than an elastic gun. At 100 feet, you have 44.1 lbs/sq in less than at the surface or about 10% less than at the surface if you are pumped to 400 lbs/sq in at the surface. 355.9 lb/sq in is still quite a bit of pressure on a piston which has about 1/2 sq in area. (Yes, I have used relative pressure rather than absolute. They both start at 1 ATA)
My gun is pumped to over 500 lb/sq in.
Personally, I don't want to use radar speed detector aimed at the spear to check speed. So if you don't want to believe 250 mph I won't argue. Would you like to play catcher at, let's see, 150 mph? How about 100 mph. I'll take ANY speed you want--I just don't want to be at the receiving end. We can agree on this? Right?
BTW, one or two nice fish and a few lobster and I'm happy for the day. I can't say as much for the commercial fisherman who manage to clean out vast areas. Even anglers will boast of finding "grouper holes" and getting an unbelievable number of fish. Dolphin (fish, not flipper) fishermen commonly catch large numbers when they find a school. They leave a hooked "schoolie" in the water to attract the rest of the school. Then it's every fish for itself--until they are all caught.
Me and my gun did not wipe out the Spanish Mackerel population. About the only thing I can't do for fish supplies is catch and release--the hole makes them sink.
So Sara, keep on shooting.
Larry Stein
OP
Sara Smiles
Guest
LADY DIVER HAS ERASED ALL REFERENCES INTHIS SITE
TO MY INDIAN NAME AND MY REFERENCES CONCERNING MY
RELATIVES. I WAS FORMALLY NOTED AS RACIALLY BIASED
AND 1 PERSON TOOK OFFENCE TO MY INDIAN NAME.....
WHAT EVER HAPPEDN TO FREE SPEECH???
MUST BE NICE TOHAVE THE POWER TO JUDGE WHAT CAN BE SAID AND WHAT CANT......IM MY OPIONION THERE ARE SEVERAL DIFFERENCES AMONG US,
IF YOU CANT REALIZE THAT YOU ARE WEARING BLINDERS. NOTHING IS WRONG WITH THAT -- VARIETY IS THE SPICE OF LIFE. HOWEVER SOME PEOPLE DO NOT HAVE A SENSE OF HUMOR.....GET OVER IT.... EVERYTHING IS NOT DIRECTED AT you PERSONALLY. SEE A SHRINK FOR YOUR ISSUES, ACCEPT WHO YOU ARE AND GET ALONG IN LIFE.
AS OF FREEDOM OF SPEACH, IT IS ONE OF OUR COUNTRIES GREATEST FREEDOMS. I CALLED NO ONE NAMES and officially RESIGN FROM THIS THREAD. Due to the editing of the content of my writing.
TO MY INDIAN NAME AND MY REFERENCES CONCERNING MY
RELATIVES. I WAS FORMALLY NOTED AS RACIALLY BIASED
AND 1 PERSON TOOK OFFENCE TO MY INDIAN NAME.....
WHAT EVER HAPPEDN TO FREE SPEECH???
MUST BE NICE TOHAVE THE POWER TO JUDGE WHAT CAN BE SAID AND WHAT CANT......IM MY OPIONION THERE ARE SEVERAL DIFFERENCES AMONG US,
IF YOU CANT REALIZE THAT YOU ARE WEARING BLINDERS. NOTHING IS WRONG WITH THAT -- VARIETY IS THE SPICE OF LIFE. HOWEVER SOME PEOPLE DO NOT HAVE A SENSE OF HUMOR.....GET OVER IT.... EVERYTHING IS NOT DIRECTED AT you PERSONALLY. SEE A SHRINK FOR YOUR ISSUES, ACCEPT WHO YOU ARE AND GET ALONG IN LIFE.
AS OF FREEDOM OF SPEACH, IT IS ONE OF OUR COUNTRIES GREATEST FREEDOMS. I CALLED NO ONE NAMES and officially RESIGN FROM THIS THREAD. Due to the editing of the content of my writing.
Spectre
Contributor
Sara,
You were asked by one member to refrain from making such comments, the response to which was for you to continue making racial slurs, rather than a simple apology [which wouldn't have resulted in any editing].
Racial slurs will not be tolorated. It was I who removed the references after complaints from multiple members, however ladydiver beat me to the punch as far as the PM.
If you have issue with our practices, I would ask you try and work it out in private before slinging mud to the members [as they have no reference to read and see what you are talking about], and I also recommend that you re-read the Terms of Service before you continue to complain.
You were asked by one member to refrain from making such comments, the response to which was for you to continue making racial slurs, rather than a simple apology [which wouldn't have resulted in any editing].
Racial slurs will not be tolorated. It was I who removed the references after complaints from multiple members, however ladydiver beat me to the punch as far as the PM.
If you have issue with our practices, I would ask you try and work it out in private before slinging mud to the members [as they have no reference to read and see what you are talking about], and I also recommend that you re-read the Terms of Service before you continue to complain.
I'm not taking sides here either way, but I do want to comment on the "freedom of speech" argument, because you see it raised frequently when someone get's edited or kicked-off the forum.
Freedom of Speech is guarenteed in the Bill of Rights insofar as the government may not infringe our right to freedom of speech. However, private entities, such as the owner of this forum, most certainly can infringe on your speech for almost any reason he sees fit, not matter how trivial. For example, someone posts on here using the Boston Red Sox logo. If the webmaster is a Yankees fan, he could kick the guy out. Wouldn't be smart, but not at all illegal or protected by law.
We are, however, protected from actions of private entities if you fall within a protected class. For example, the forum owners can not discreminate on the basis of race or gender. A forum rule of "no African-Americans" would be illigal and subject this forum to a potential lawsuit.
In short, if you don't like the way your posts are edited, you shouldn't cry "freedom of speech", because it has no application here.
King Kong Matt
Contributor
If I thought for more than 2 seconds that the webmaster was a Yankees fan, he wouldn't have to kick me out...I would voluntarily leave.
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Dr. Larry,
You make a convincing case regarding pneumatic guns. I don't know any specifics regarding velocity, certainly either type will punch a hole through anyone unlucky enough to be on the other end!
My experience as a competition freediver has shown that the weapon of choice is the band gun, specifically long, wooden guns. These guns are preffered because they are quieter, more accurate, and maintain their power regardless of depth. This is only my opinion but I'm sticking to it!
Tom
I don't spearfish. I do shoot defensive pistol competitively. First rule, don't point a weapon at anything you are are not willing to destroy. Sounds like a decent idea to follow with spearguns as well.
If someone pointed a loaded weapon at me, I would follow Tampascott's suggestion of taking the weapon. Then, while the diver was egressing, I'd discharge the weapon, weight it and give it a free ride to the bottom. If the diver objected, I'd suggest that he/she join it.
If someone pointed a loaded weapon at me, I would follow Tampascott's suggestion of taking the weapon. Then, while the diver was egressing, I'd discharge the weapon, weight it and give it a free ride to the bottom. If the diver objected, I'd suggest that he/she join it.
Laurence Stein DDS
Medical Moderator
WreckWriter, I agree, competition guns are long, band guns, usually wood. The reason is simple. They are almost silent and with the long shaft, they have long range. The longer the spear is more accurate and has a lot of mass for penetration. In order to load a pneumatic gun, you have to have sufficient reach and sufficient strength to overcome the considerable preload on the piston. Band guns allow for better reach and longer shafts. There is often an intermediate position the band can be cocked to before placing the elastic at it greatest extention and power.
Pneumatic guns of long length must be loaded with one hand on the spearhead with a loader and the other supporting the barrel. You cannot two hand the spear into the barrel. A power selector switch helps, but it doesn't do a thing when you first start to load the gun if it has been discharged on full power. If you manage to pull the spear back, on the low power setting, you can back off and start again with less force--until you get to the point you left of at during your first attempt to load.
Nemrod used to make a gun which had a power lever that could be used to compress the air AFTER cocking. It was a bear to load.
Pneumatic guns have more moving parts and if a seal breaks, your done for the day. Band guns will usually fail at the elastic and that can be changed on the boat. Band guns on the otherhand are just about guaranteed to have a band failure...pneumatics can go 2-3 years between failures. If you have ever seen anyone who has been unlucky enough to be loading or unloading a band gun when the elastic breaks, you know that it can make for a severe injury. The wire attached to the elastic is going to be pulled through one hand or the other when the elastic breaks--nasty. One manufacturer uses kevlar line instead of steel wire. It's quieter and probably safer--although I bet it's gonna hurt if your handling the elastic when it breaks.
For all its, disadvantages, a pneumatic gun can be loaded more quickly than a band gun. You don't have to position the elastics over the shaft first and then string the line. A pneumatic gun shoots almost like a pistol. It goes exactly where you aim it. Many band guns have a slight over or under shoot depending on how precisely the elastics line up with the centerline of the shaft. If you overpower a band gun it becomes inaccurate. Pneumatic guns can be "hip shot" they are so accurate. You don't have to look over the gun to aim. It's much like point shooting with a pistol--you don't actually aim, you simply know where it will impact.
So, all in all, yes, a long band gun is for competition but a pneumatic is great for small spaces and quick shots. I just happen to like pneumatics for their accuracy but they are noisy if the spear doesn't hit the target within the length of the spear...otherwise, the piston impacts the front of the barrel and makes a "smack" which is quite loud.
Some people swear by pneumatics and some by band guns. It's a personal preference.
Larry Stein
Pneumatic guns of long length must be loaded with one hand on the spearhead with a loader and the other supporting the barrel. You cannot two hand the spear into the barrel. A power selector switch helps, but it doesn't do a thing when you first start to load the gun if it has been discharged on full power. If you manage to pull the spear back, on the low power setting, you can back off and start again with less force--until you get to the point you left of at during your first attempt to load.
Nemrod used to make a gun which had a power lever that could be used to compress the air AFTER cocking. It was a bear to load.
Pneumatic guns have more moving parts and if a seal breaks, your done for the day. Band guns will usually fail at the elastic and that can be changed on the boat. Band guns on the otherhand are just about guaranteed to have a band failure...pneumatics can go 2-3 years between failures. If you have ever seen anyone who has been unlucky enough to be loading or unloading a band gun when the elastic breaks, you know that it can make for a severe injury. The wire attached to the elastic is going to be pulled through one hand or the other when the elastic breaks--nasty. One manufacturer uses kevlar line instead of steel wire. It's quieter and probably safer--although I bet it's gonna hurt if your handling the elastic when it breaks.
For all its, disadvantages, a pneumatic gun can be loaded more quickly than a band gun. You don't have to position the elastics over the shaft first and then string the line. A pneumatic gun shoots almost like a pistol. It goes exactly where you aim it. Many band guns have a slight over or under shoot depending on how precisely the elastics line up with the centerline of the shaft. If you overpower a band gun it becomes inaccurate. Pneumatic guns can be "hip shot" they are so accurate. You don't have to look over the gun to aim. It's much like point shooting with a pistol--you don't actually aim, you simply know where it will impact.
So, all in all, yes, a long band gun is for competition but a pneumatic is great for small spaces and quick shots. I just happen to like pneumatics for their accuracy but they are noisy if the spear doesn't hit the target within the length of the spear...otherwise, the piston impacts the front of the barrel and makes a "smack" which is quite loud.
Some people swear by pneumatics and some by band guns. It's a personal preference.
Larry Stein
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