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Gun Geek

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  1. Overall it was a pretty good episode. I have no doubt that the 23 degree entry angle into the pool was most of the reason the rifle bullets broke up. It would have been much more interesting to see what the results would be with the bullets all hitting the surface of the water at a 90 degree angle.

    It was beautiful to see the carefully built vertical tank go to pieces when they shot the 12 gauge. Firing a 3" magnum slug into a 8 foot column of water about 2x2 feet square, the plexiglass didn't have a chance.  :lol:

    I think the bullets broke up because they were going fast. I don't thenk the angle had anything to do with it. The would probably break up at 90 too. Guess that's another think they should test.

  2. Virtually all the new shows on cable seem to be produced by the same people, or at least people that run in the same social circles.  It doesn't matter what the subject is, it's going to be "X-Treme Crotcheting!,"  or some similar BS.  All TV has been bastardized into juvenile, "Extreme", melodramas to pique the interest of the median, urban 12 year old male.  No other form of packaging is permitted.  Gen-X rules the roost and all things media are going to suck until they get fired or run over by a bus.  If you're looking for more, you're going to be waiting a very long time. 

    I'll just bet that if you spoke to the show hosts (off the record) about how their material was presented that:

    (1) They have absolutely NO voice in the matter

    and

    (2) They aren't any happier about it than you are.

    I kinda came to the same conclusion, and I'm pretty disappointed by it all.

  3. Since all discussion, I say you have a ground loop problem because of the soil and limestone. So no matter what you do the grounded dock has got some potential. Why not try taking a piece of bare copper ground wire attach to dock and toss in the water. Since copper corrision is conductive it shouldn't lose it usefullness over time.

    Out in country where we don't have three phase. Just the hot line and the ground line. Every pole is tied to ground line and every step down transformer is tied to the ground line, and my house neutral is tied to the ground line.

    Not enough surface area on the wire (unless it was 100' long, in which case it would foul on the bottom and rip off as the dock went up and down).

    This is why EricW and I discussed metal plates suspended under the dock. It may be in the plan as well.

  4. So tell us the results!  How deep do bullets go into the water and still remain dangerous?  :huh:

    Well, they fired a 9mm into a tank of water and it was lethal to about 8' I think. Then they fired a slug into the tank. It was lethal to the same 8', but the blast broke their tank. The tank was an angle iron frame with plexiglas screwed and glued so you could see through the sides. The shotgun blast cracked the Plexiglas and the most of the water ran out (onto their shop floor).

    They moved to s swimming pool and were firing at an angle (25 degrees, I think). The muzzle loader went wildy off course when it hit the water. The other rifle bullets (223, 30-6, 50BMG) all broke up with in 18" of the surface. Some fragments continued on and might have been dangerous, so the conclusion was that at 3' you'd be OK as long as they were shooting high powered rifles at an angle.

    The angle thing is a reasonable constraint. If you're going to get shot at, The shooters will probably be at a distance on the shore - producing an angle. I wish they had re-tested the handgun at the angle, to see if it would go deeper.

    Here's the logic I didn't like:

    50 BMG is "fearsome" or "unbelievable" and banned in Kalifornia - they discussed it on the show. The 30-06 and the 223 are "fearsome" and unbelievable" as well - so shouldn't they also be banned?

  5. Caught a TiVo'd episode of Mythbusters last night.

    One of the myths was that you'd be safe if you dove underwater when being shot at (i.e. water stopped the bullets). Result was that a slower handgun bullet would penetrate deeper (like 8') but high speed rifle bullets broke up a foot or so into the water and wouldn't get you.

    They even shot a 50BMG into the water.

    Cool show!

    Problem was with the voice-over guy. He consistiently used terms like "fearsome" and "dangerous" and "unbelievable" to describe the speed of the bullets from a rifle (they used a muzzle loader, AR, a Garand and the 50). Maybe I'm over sensitive, but that seems like a very good way to fuel the debates over gun control in general - it conditions non shooters to think that rifles are some amazingly awful force that has to be controlled.

    I guess I'm disappointed. One of the guys (Jamie) is obviously an enthusiast (he handloads, many of the guns used in the show are his, and they mentioned when they shot the ML that Jamie made the bullets).

    Sorry if this is too close to politics, for this board, but I had to speak up!

  6. CZs make me nervous.

    I've seen 3 of them as a USPA RO and an IDPA SO. 2 of the 3 have been ND'd and the guys DQ'd. Actually had one guy argue that since you have to manually drop the hammer, an AD (he insisted it was an AD, not ND) was going to happen and that he should not be DQ'd. :lol:

    I understand why the CZs are built the way they are and I have shot one (and liked it), but to date the failure rate is too high and I will remain very vigilant when I see one.

    "do you trust yourself & your skill, or do you place your trust 100% in a mechanical device that you did not build?"

    Obviously I put 100% trust in something I did not build. Everytime the gun goes off, the only think keeping it from blowing my hand and face off is the gun. Sorry, but this is a non-starter argument. When a de-cocker is used the gun is pointed at the berm -I'm not putting 100% trust in it. If it fails, the AD (this time it is an AD if the gun fails) goes in a safe direction. That's not trust.

    Problems with CZ will be user related, so I'm not advocating a ban. But as an RO/SO I will be damn sure they are pointed in a safe direction when de-cocking. If I see a CZ at LMAR, I make them slow down the process and be very deliberate about where it is pointed with they decock.

  7. Talked to an engineer at a local commercial contractor and got an earful about how much of a bitch ground loops are. He confirmed that it has been more of a problem in the dry weather (we did get some rain from the hurricane). Told me the story of this being a big problem on horse farms - horse standing on ground that is higher potential than the water - gets shocked and won't drink. We have big $$ horse farms around here.

    Here's the interesting part. He said if it truly is a ground loop, then there is likely nothing to be done that isn't major $$$ (10's of thousands). AND he said that it is common around swimming pools that there is some potential between the ladders and the water, and that code allows 4 - 6 v! I'm seeing 1.5v. He rattled off the measured voltages at the public pools around town. He knows it because he checks it. His point was, if it was shock from a ground loop, don't worry about it! He said to make sure the dock was properly grounded so that a stray hot would not light up the dock, and move on. EEEEK!

    OK, here's the plan as of now (I tell you this because it will take some time and I don't want you to think I let this go to sleep):

    1) Disconnect the service N from the ground rod (If I can do it safely) and see if the shock is still there. If it is, then I am satisfied that this is truly a ground loop problem and not a leakage (N to G) problem.

    2) Finish cleaning up some details disconnecting the N to the frame of the dock.

    3) I don't like the Triplex going to the dock with a live exposed N, so I'm going to look for a different kind of wire (got some in mind that is 4 insutlated conductors + bare ground in insulation rated for wet locations. It feels like a giant extension cord and I think it is big $$$).

    OR

    4) I may use 2 runs (gives me 4 insulated conductors) of Triplex and just have the metal wire for mechanical connection. Probably will ground it to make sure there's no stray voltages.

    5) Drive a couple of ground rods up the hill to improve grounding. It is code here (as of just a little while ago) that you have 2 ground rods (or 1 big honker).

    This will take a little time, so I'll repost when I get my list done.

    Keep the ideas coming if you have more!

  8. GG I understand your problem, I don't have a solution for sure. You can try unbonding the nuetral and ground (WIth power disconnected) and check for potential between the water and Dock that would tell you if George's idea is part or all of the issue. (If there is still a potential there I would definitely find a way to ground the Dock to the water or shore.)  :ph34r:

    I have disconnected the H (via breakers) and the N (took it apart) and left the ground connected. Shock is still there. I have not disconnected the U Co N from the ground rod to see if the shock still exists.

    If it does not (ie. the dock ground wire does not touch the U Co N anywhere, but is still connected to the ground rod), the U Co might have ground loop problems of their own. This would dump a bunch of current into my ground point which would cause a voltage to develop.

    I'll investigate this (though I'm not sure how to disconnect stuff - it will take the power down in the house when I do).

  9. I love it!

    Keep it coming guys...

    This is the problem that I see that GG has:

    1. triplex is run to the dock (2 hots, 1 neutral) run from panel at the house.

    2. the neutral was tied to the frame (correct GG???) which esentially made the neutral  the ground.

    1) Yes - triplex terminates in a load center on the dock. The neutral goes to an unbonded (insulated) bus bar in the load center and all white wires gonnect to this bus. A ground was subsequently run down the hill and connected to a bonded (connected to the box which is connected to the frame) bar in the box - see below.

    2) Yes

    My solution:

    1. run a quadraplex wire ( 2 hots, 1 insulated neutral, 1 bare ground "static line")

    and bond the metal dock to the ground wire.

    2. you need to put a ground rod by the bank.  if you can't get a rod to go straight down then bend the rod at the end and dig a shallow trench about 8 inches deap and lay it in the ground, if you ask a inspector nicely, he'll tell you this is perfecty ok, all 8 feet are in the ground.

    1) Sorta did this - in hope of a fix I ran an insulated ground wire from the ground rod up the hill. Disconnected the N from the frame, connected the G - still get the shock

    2) Cain't do it. The bank is rock (limestone). Any soil there (and there is very little) will be only few inches thick and likely to wash away the next time the water comes up. The only soil that might be more than 3" deep is at the bottom the lake, 40' to 50' below the dock.

  10. My carry gun is on its second rebuild, over 90k rounds thru it now...shot IDPA with it for 4 yrs and carried it since 95...beautiful again, 100% everytime....

    Limited is an STI Edge worked over by the master in Houston, Jimenea....and it too is beautiful....both are works of art which shoot beyond my abilities as are all Eddie's guns...cannot say enough about his work...great stuff..

    As I said in another thread...there is NO reason that it cannot be beautiful and run 100 percent, and when you pay as much as we all do for a uber tricked out blaster there is no reason it shouldn't be beautiful...if you settle for ugly, someone bent you over..

    I find that the "ugly" comes from the use in action pistol sports. I don't think I know of any that see lots use (and dryfire, holstering, reloading) that don't quickly get a bad case of the uglies.

    Beautiful can certainly run 100%, but if it used for training and matches, it won't stay beautiful very long.

    Well, the wear of use is a beautiful thing - that's what I tell myself as I get older :(

  11. GG,

    You might try contacting your electrical utility under a pseudonym to see if they have any solutions/ideas for achieving a solid ground into limestone.  This can't be the first time this has happened.  We have lots of basalt where I live, so I'm sure that this issue has been dealt with before. 

    FWIW,  I do understand what your problem is.  ;)

    It is good to be understood.

    I talked to the U Co this morning. Their answer was call an electrician. I think this is a standard to keep themselves from getting sued.

    I'm working to find an electrician who will help with out turning me over to the fuzz. Actually I don't think you can get "turned in". What happens is that if you need help from the U Co they won't give it to you unless there is an electrican involved and things are already up to snuff. Which, I guess makes sense...

  12. So on your dock, don't strap the neutral and ground together. Put a ground stake in and tie all the green third prongs to that and your shock problem will go away without a lot of digging and work. I would still put a Gfi on that circuit so some fool who uses a power and falls in water with it won't die. Nice 10 foot ground rod on edge of lack will make a wonderful ground, however if you strap neutral and grounds together you may have best ground in neighborhood and have lots of juice flowing towards it.

    It just like water all seeking the lowest potential.

    Ahhhhh, nobody's listening, I'll go over this again...

    The N & G are NOT tied together - they never have been.

    At one time there was no G - The N was tied to the frame of the dock (this is really bad). Now the N is isolated and the G is tied to the dock. The G comes directly off of the ground rod up the hill.

    You still get shocked, even if the power is shut off and the N is disconnected (leaving only the G connected). Disconnect the G and the shock goes away.

    Putting in a ground stake on the shore is not an option (unless I rent one of those self propelled drills they use to make blast holes for clearing road right of way). The shore of the lake is solid limestone.

    I don't have 10' of topsoil at the top of the hill for a ground rod only 3 or 4' then you hit limestone.

    All plugs are GFCI, and I have tested them by dropping a hot wire into the water.

    Not picking on you cking - this thread has gotten a little hard to follow, but it is very interesting, so keep it all coming!

  13. What I am about to say may be unpopular here and if it is so be it. Your girlfriend should not ask for anything more than to have her costs covered and a letter of apology. That's it.

    Don't get me wrong, what happened to her sucks big time but at the end of the day she still has her health.

    Some of you have made snide comments about Doctors and Hospital and those comments are 100% out of line. I come from a large family with 6 of them being doctor's with one more on the way. They wake up every morning hoping to make the lives of their patients better. They don't wake up and check their stock portfolio's. They work long hours and put up with tons of $hit that John Q public never sees, and yes they do make mistakes from time to time. As we all do no matter how hard we try and so do the people that work for them and the hospitals. I doubt very much that any of them go to work every day wondering how they can ruin someones life. Bad things happen to very good people every day. It's just a fact of life.

    My father's GP misdiagnosed his prostate cancer. What should have been easy treat ended up as type 3 cancer and the advice to go home and get your affiars in order. He opted to undergo a radical treatment that took care of the cancer (10 years later he is still going strong) but left him chemically castrated. He decided not to sue his GP for two reasons. The first being that it would never undo what he has gone through. You can't put a price on that. And secondly and more importantly health care isn't a zero sum game. Every dollar that your doctor has to spend on malpractice insurance has to come from somewhere. There people out there that can't afford insurance and can't even afford to pay the $75 for an office visit. Their quality of life stinks becuase lawsuits and and settlements make health care entirely unaffordable to them.

    I leave you with this. Recently a cousin of mine closed her OB/GYN practice here in NJ. Every year she would sit down and figure out what it cost her to open her doors every year. When you added up the costs she would have to make $600,000 a year just to break even. $250,000 right off the bat went towards malpractice insurance and the rest towards office space, salary, equipment, etc.... Her last full year with the practice she made roughly $78,000 when it was all said and done. Sounds like a lot of money, and it is, but when you calaculate how much time she spent in the office and at the hospital nights and weekends it worked out to something stupid like $27 dollars an hour and no personal life.

    Any way I am glad to here you girlfriend is doing fine. I hope that out of this whole fiasco she can appreciate who fragile life is. Having survived a couple close calls myself I know I do.

    X2 X2 X2

    neck this is not unpopular with me!

    Cover your out-of-pocket, your lost wages (even $$ spent by family members), etc. and forget the rest.

    You're in danger of falling into the "lawsuit lottery" trap (mentioned b4) and helping to drive up the cost of med care all around. Hospitals & Drs should pay reasonably for the consequences of true negligent mistakes - not be punished because of some short term stress and a mistake they caught.

    Unless I missed something in the post, where does the desire to get medical expenses covered for the other guy come form? If the other person was in that bad of shape, there were likely symptoms and when the x-rays came back neg (while probably lots of other tests were positive), I'll bet the hospital re-ran things and figured it out.

    Sorry - I know, sounds a little "Libertarian". I don't mean to be, but as I get older...

    2 more cents :rolleyes:

  14. You talking about the Stoney Point OAL gauge?

    $30 +/- $2 is about right for this product. I don't think you'll find it significantly cheaper anywhere.

    Tell us a little more about what you're trying to do and someone might have a slick work around...

  15. Here is a much more correct diagram showing how power really is distributed and wired for both industry and household usage. Note the N-G bond occurs at the XFMR, I shudder when I see this bonded in service boxes, or right to the cold water/earth ground point the service box connects to. Nooooooooo! Always do it at the pole!

    George:

    I think grounding at the service is common practice - maybe even recommended practice. Check the graphic below, the source is: http://www.enm.com/training/siemenscourses/load_2.pdf. This is exactly how my dock is now wired. Where they have a "Downstream Loadcenter" is the loadcenter on the dock. They show it bonded to the enclosure and to an enclosure around a load - the frame of the dock.

    post-3004-1121151865_thumb.jpg

    post-3004-1121152184_thumb.jpg

  16. Just to be sure I've conveyed this right:

    When the N was connected to the dock frame, shock occured, power on or power off.

    A ground wire was added - it connects directly to the ground rod. The N is NOT now connected to the frame. The G is connected to the frame.

    Shock occurs with the G connected to the frame power on or power off.

    The G & N are connected (bonded in the vernacular) - in this case at the meter where the service enters the house. After that they do not touch. In the main breaker box of the house, they are at the same potential (0v on a meter) and 0 ohms resistance when measured with a meter. Check out these diagrams - they are not my work (this upload stuff is cool).

    post-3004-1121148546_thumb.jpg

    post-3004-1121148563_thumb.jpg

  17. Chuck the reason you get shocked in this situation, is that with the neutral tied to the frame, the only path to ground was tru the water, and when a body touched the dock, you became a better conductor than the water, hence the current/shock going tru youl, back to the water on to ground.  That's why you don't tie the neutral to anything.  one other bad thing about sharing 1 neutral between 2 hots on different phases (this is a common thing in house wiring, it save money and time to run 12-3 piece of romex wire around a living room)  if you lift the neutral or lose the neutral some how, you will put 240 volts on your tv set, stereo, etc, and they don't like that.

    I guess this is a EE gathering discussion, sort off.  I left NMSU in 95 with 18 hours left to get my EE in digital microelectonics.  got burned out so I figured i'd go work construction again for a couple of year, somehow ended up as a mine electrician and haven't been able to get away form the sunshine and clean air (after they shut down our smelter) and pay.  Now i'm to onery to put up with a professor, especially some of the jerks I had 10 years ago.  On the plus not I attended a class a couple of years ago for power generation and distriution for our power house (gas boilers and gas turbine units)  the instuctor was from Cadick corporation and the instructor explained in two days what I was supposed to have learn in EE214 and 314 (power systems)  This guy was a power grid operator in NY for 35 years and now he certifies all the system operator in the nation, something to be said for on the job learning

    GG you might try a sheet of SS plate about a 10 guage, our SX/EX (giant 4160 battery) uses them and they seem to work pretty good.  The limestone might be acidic enough to keep alge from growing.

    Just to be clear: the neutral is NOT tied to the frame, the ground wire is tied to the frame (which is exactly what most electricians will tell you to do). You still get shocked if the power is turned off. The shock is not associated with the AC power. It is associated with 2 points on the earth ground being at a different potential.

    That's why this is an interesting problem - you do stuff like you are supposed to do and it produces a shock.

    Set it up against code (electrically float the dock by isolating it from from the neutral and the phase) and there is no shock - though it will likely be be unsafe if there is a problem.

  18. The subject of grounding for your dock can found in the NEC 2005, article 553 "floating buildings".

    The whole point of grounding is to get/make everything at a single potential.  You need to change your cable out to a 4 wire setup (2 hots, 1 neutral, 1 ground)  set up a j-box on the edge of the lake/pond and run the power cable into it, bond the ground to it and drive a ground rod on the edge of the lake/pond, then complete the run to the dock.  bond all the metal parts on the dock to ground conductor. Eric's comment about not bonding the dock to ground is 100% wrong (sorry about that, but its true) 

    You probably have voltage on you neutral, and without a ground to check it to you will never know.  Which could be a problem upstream of the power source.  The other source could be induction on the neutral, which would be the same case above, especially on a long power run.

    out here where i work (copper smelter, power house, I'm a industrial electrican)  we have a set of 120/240 signal cable that are about 8 feet below a 13,800 volt run of triplex power cables.  they induce about 90-100 volts dc onto the signal cables, enought to get you attention if your not careful, so your 1.5 Vdc should be about right.

    John:

    Got a link to this NEC article?

  19. Have the utility co check for an open neutral on the system--Have seen a similar problem with a swimming pool. the feed to the house was bad. also a check would be to amp clamp the grounding electrode conductor going to the rod- any current could indicate a open neutral as well

    Something like this will be my next step. I'm going ot go back to basics and make sure the connections are good.

    After that, I'm going to explore better grounding at the top of the hill - maybe several ground rods.

    I've been considering talking to the utility co, but that may open a kettle of fish that I don't want to open.

  20. Let me ask a question or two : Why do you thing the shock is due to your dock? Is there some other possible source in the lake for the current? You stated

    "You do not get a shock if you disconnect both the neutral and the ground wire (did this only with the phases off) Re-connect the either the neutral or ground and the shock comes back."

    This tells me that the lake is charged somehow and "discharges" into your ground line through the dock (and the swimmer). If the dock is floating electrically, it will eventually reach equalibrium with the charge of the lake so when the swimmer in the lake touches the dock, they feel no difference in charge or shock.  If the dock is grounded, there is some current flowing through the lake/dock interface which probably has quite a bit of impedance.  The shock comes from the swimmer shorting out the impedance between the dock and the lake with their body.

    Just some late night thoughts...

    You're exactly right - there is a discharge from the lake into the dock (or the other way around). That discharge is because the wire connected to the ground rod up the hill and the lake are at different potentials. If you disconnect the wire from the ground rod ("ground" wire and neutral) then the doc can reach steady state and, since the dock is floating electrically, it will reach the same charge as the lake, and there will be no shock.

    The problem with having the dock float (not grounded) is that it will be dangerous if a hot wire touches it. The frame of the dock will be at 110v wrt the lake. A swimmer touching the ladder/dock will be the primary discharge path, and ZAP.

    This is a well known and well documented problem around marinas (and one of the reasons you're not supposed to swim around them). Big aluminium hulled boat has some snafu with wiring - hot lead touches the aluminium, and doesn't trip a breaker cause the hull isn't grounded. Hull sits at 110. Swimmer gets close to that and goes into cardiac arrest. Death is ruled a drowning!

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