DIY shooting rest and a Blue Wonder followup report – Part 3

by B.B. Pelletier

Today we have a short guest blog and a followup report on the Blue Wonder cold blue project I’ve been working on. First the guest blog.

Guest blogger
This is Mike’s first guest blog. He needed a rifle rest, so he decided to make one instead of buy something ready-made. His uses simple, everyday items that are inexpensive and readily available. Even if you have to buy some of these things, it’s an economical project.

If you’d like to write a guest post for this blog, please email me.

Bloggers must be proficient in the simple html that Blogger software uses, know how to take clear photos and size them for the internet (if their post requires them) and they must use proper English. We will edit each submission, but we won’t work on any submission that contains gross misspellings and/or grammatical errors.

by Mike S.


My Gamo CFX resting on my homemade shooting rest.

Some history
Every year I go on a trip where a group of us target shoot for the weekend. I use my .22 Gamo CFX, and the rest of the crew shoots .22 rimfires. The range is about 75-90 yards, and we all shoot from a benchrest position. For years, I couldn’t come close to matching the accuracy of the rimfires. In fact, I couldn’t consistently hit a 5-gallon bucket at 75 yards.

I knew my gun was capable of better accuracy. After doing hours of online research, I learned that firing a springer from any hard surface will completely ruin accuracy. The vibrations caused by the mainspring will shift your aim before the pellet leaves the barrel.

So, I made cushions on which I could rest my rifle. They’re designed to absorb the vibrations. My accuracy improved to where I was up to par, and–in some cases–out-shooting the rimfires. The cushions are very cheap and easy to make from stuff around the house. They’re weatherproof and can be built in less than 20 minutes.


It’s not a showcase item, but it’s functional and does the job!

Materials Needed

  • Plastic bag (a grocery sack or Ziplock bag will do)
  • 5″ strip of fiberglass insulation
  • 1″x6″ board cut 6.5″ in length
  • Almighty duct tape

  • Just assemble a few inexpensive, ordinary items from around the house to make your rifle rest.

    Procedure
    Climb into your attic or crawlspace and cut a 5″ strip of fiberglass insulation. Most insulation is about 16″ wide. I used R13, but whatever you have should be fine. Cut the insulation in half so you have two 8″x5″ pieces. Place one half on top of the other half.


    A chunk of fiberglass insulation…yours may be pink or some other color.

    Slide the inslation into the bag. Take the slack out of the bag and tape it on the bottom. Don’t pull the bag too tight. You want the fiberglass to be uncompressed.


    Assembly is a cinch!

    Tape the bag to the piece of wood, taking up any additional slack in the bag. I cut a few additional pieces of wood so I could change the height of my rest. Now, lay your rifle on the bag and fire away!

    [Editor's note: When handling fiberglass insulation, be sure to breathe through a half-face respirator with replaceable HEPA filters. A paper dust filter is not considered adequate filtration for fiberglass particles. Brief exposure is not likely to cause any damage, but handling and cutting the fiberglass batts may expose you to particles that have been shed into the air you breathe. If any part of the fiberglass in your shooting bag becomes exposed, re-cover it right away. Prolonged exposure to fiberglass insulation can cause nosebleeds and other respiratory problems.]

    Blue Wonder update report – Part 3

    Part 1
    Part 2

    Well, I thought I was going to have to eat some crow on this one. In Part 2, I blued a new barrel for a .17 HM2 rifle a friend put together for me, and the job turned out so beautiful that I raved about it. Then the comments came in. Some shooters were concerned about the job rusting fast and one person asked about matching the old blue. I answered the matching question to the best of my ability, but today I will shed some new light on both topics (rusting and matching).

    About four days after I did the barrel, I happened to pick up the gun in my closet and was astounded to see that it had rusted almost 100 percent! The rust was extremely fine and even over the surface. When I picked up the gun and held the barrel my hands turned dark brown.

    I was very disheartened by this. I knew I had to tell all of you, especially after recommending the product so highly in Part 2, but I wanted to think about it for a few days. I had also bragged on the job to my friend who rebarrelled the rifle for me. And now he wanted to see it shoot, so I had to show the rusty blue job to him also.

    Then it hit me. Blue Wonder couldn’t possibly have remained in business for all these years if their product always rusted. Surely, by now, there would be a great hue and cry about it and the internet would be full of warnings not to use it. I did find some warnings, but you can find warnings about almost anything if you look. There weren’t the number of warnings I would expect if this product were pure snake oil (no slight meant to the oil by that name), so I reckoned I must have done something wrong.

    Let’s see. I cleaned the surface with acetone that several of you said wasn’t good. That might be it. So, I read the Blue Wonder instructions online once more and found that they made no mention whatsoever of de-greasing the metal after cleaning it with Blue Wonder gun cleaner. Okay, so that step was unnecessary and wrong.

    They also cautioned you about which oil to use after the job is finished. They said to use Break Free. I used Ballistol. So, that was point of departure number two. On the next go-round, I would not use acetone and I would finish with Break Free.

    I removed the action from the stock and went to work removing the rust with 0000 steel wool. It came off immediately (1-2 minutes) and left the gun looking almost as it did after the initial bluing job. I toyed with the idea of stopping right there, but decided to go on and redo the whole barrel because I wanted to report on the entire application, not just a patch job.

    After the steel wool treatment, the metal surface was free from all rust. I then cleaned the entire surface with Blue Wonder gun cleaner, just like the directions said. Then, I heated the barrel with a propane torch, again following the directions. Like before, it was hard to get the entire barrel up to the same temperature, but I got it all very warm to the touch. Speaking of touch, you are cautioned in the directions not to touch the metal with your hands at this point, so I had plenty of paper towels to use when I held things.

    Next, the Blue Wonder bluing solution was applied. I remembered to shake the bottle before every application. Although the barrel did not seem to get any darker this time, some of the imperfections close to the muzzle around the front sight went away as I applied the solution. The last step was to apply the developer. Then, the metal parts were set aside for a couple hours to fully develop. Remember–this is a chemical process related to photography.

    When it had developed, I wiped down the whole surface with Break Free and set the still-wet barreled action aside for the rest of the evening. The next morning, I dried the barrel and installed the action in the stock. I took the rifle out to the range, where I shot a 3/4″ five-shot group at 50 yards using peep sights. Yeah–this rifle can shoot!

    The guy who installed the barrel got to see the job and was very impressed. So was I. This was the first time I’d seen the job in bright daylight, and it was even better than I had reported before–though some of that was undoubtedly because of the second application.

    I noticed in the sunlight that Blue Wonder has a bronze undertone to it. That must be due to the gold in the solution. The color doesn’t match any blue job I’ve ever seen. But back under incandescent or fluorescent lighting (normal house lights) it does match. So you have to make a choice. If you plan to re-blue the entire gun, it will stand up even outdoors; but if you’re doing a spot job, there will surely be a color difference in the sun. With indoor lighting, I cannot see any difference, but I’m colorblind, so proceed at your own risk.


    This photo shows the bronze or gold undertone of the Blue Wonder blue. Compare the color of the barrel to that of the front sight that was blued by a hot salt bath black oxide process. Any uneveness that you see in this picture is the result of fingerprints–not the blue job, which is remarkably even.

    As I write this, it’s been four full days since I did the second job, and the gun still shows no signs of rusting. The blue is still dark, even and very shiny. I’m still very thrilled with the results. However, the one thing we still don’t know is how well the blue will hold up to handling. The best test for this might be a revolver carried in a leather holster. Nothing wears blue faster than a leather holster. But since I don’t carry holstered guns, this isn’t going to work for me. Besides, I don’t have anything to compare it to, so any report would simply be conjecture. I guess I need a cowboy action shooter to test this for me.

    Speaking of cowboy action shooters, a friend from 40 years ago when I was a gunfighter at Frontier Village in San Jose recently contacted me with a request. Seems I sold him a Colt single-action for $150 and it recently lettered at Colt! That means Colt has a record of the gun in their files and can tell when it was sold, who it was sold to, the barrel length, caliber and original finish of the gun. It might be worth $3,000-3,500 today. He sent me a copy of the letter of authenticity, asking me for the details of how and where I came by the gun.

    Here is a lesson in gun etiquette. When you find that a gun you acquired is better than you thought, do not have the insensitivity to ask the person you bought it from any questions about it, and for gosh sakes don’t tell him what it may be worth. That’s like taking a trophy wife to your high school reunion and introducing her to the girl who turned down your proposal 40 years ago.

    Unless, of course, that is your intention. I wonder?

    67 thoughts on “DIY shooting rest and a Blue Wonder followup report – Part 3

    1. Hi BB…

      Very nice article on blueing, i hope the second try would last good for the barrel job…

      BTW, would you please post some picture while you're a boy or young man, i wonder how you look like when you were a boy, teenagaer, or middle age… (you're in GOLDEN AGE now for sure)… also, please post some picture whith Mrs.BB together… i really wonder what you both looks like back then… i honestly want to see the young airgun lover if you dont mind =)

      hope you could figure out an article which can include those oldies fotos… thanks for considering…

      Keep up the GREAT WORK BB…

      Your BIG fan

      Iyonk…


    2. Mike,
      Very creative. I'm going to try this myself. You made it look so easy. Made me think of how I bench rest shoot. Again, the obvious eludes me, I always rest my hand on the bag with the gun on top of my hand, even with my pneumatics. I'm thinking, now, with the pneumatics I shouldn't do that and just rest the gun on the bag. I know for the artillery hold for springers I have to have my hand involved but maybe I need to get it out of the way for my pneumatics. I'll give it a try with you clever idea and see what happens. Maybe it'll eliminate some of that heart beat effect.

      BB,
      Please let us know how your bluing job looks in a couple weeks. I want to do this to an old shotgun I have but you be the Guinea pig.

      -Chuck


    3. Mike,

      What a neat idea and way to make a bench rest "bag" for a springer. Thanks for taking your time to share it with us. Yes I'll be giving it a try.

      Mr B.


    4. CJr,

      Try shooting Ms M and Mr T in "normal" bench rest style, ie, front of stock on Mike's bag, tripod, etc.(see Cheaper than Dirt). Right hand working the trigger with its attached elbow resting on the bench.

      Place your left elbow on the bench and use your left hand to help support and control the elevation of your gun. That hand should be positioned near the toe of the stock or end of the CO2 tank.

      To find out if you're doing this correctly, close your eyes for a second instead of pressing the trigger all the way to take the shot. When you open them the cross hairs should still be on the target.

      A picture of two would sure have been worth at least 80% of these words. I hope you can understand this, because it works well for me. Give it a try and let me know what you think.

      Mr B.


    5. Mr. B,
      No picture needed. I understood your instructions. They were very clear to me. I will use them. I'm left handed so I'll have to hang from the rafters, upside down to do it but it sounds like it'll be worth the effort (<:j
      -Chuck



    6. Mr.B,
      Also, I'll tell you what doesn't help matters, and that is switching from a rifle stock to a round CO2 cylinder and back. Talk about a different cheek weld!!!

      -Chuck


    7. CJr,

      Yes I can really related to what you said. I've been trying to shoot some my guns one after another offhand at 4 metal spinners: Talon SS on CO2, RWS 350 Magnum, Discovery, and the Diana 35. I have yet to go through the line up and clean the course, but it will happen!

      Mr B.


    8. Volvo -let us know how the 44/40 turns out…I know oxpho-blue is pretty popular…..both seem easy to use…which is always a plus.

      My van is black….if it ever rusts….I'm going to cold blue it…lol!!!!


    9. BB,
      Another Topic…

      Would you happen to know the reason why then delivery of the AirForce "Edge" keeps on slipping? I have been anxiously waiting for it since April of 2008.

      Did the release of the new Crosman Challenger cause AirForce to have second thoughts about the "Edge"?

      My order for the AirForce Diopter (front)sight has also been in back order for months. It seems that AirForce is not actively working on these products.

      Should I wait or just get the Crosman Challenger? I called PA but the sales rep could not give me any definitive answer.

      Thanks for any info.

      Stingray


    10. B.B.

      Good questions from Stingray.

      Mike, very ingenious. I seem to remember PA selling a gel pad for a similar purpose. There's also resting the rifle on your hand although I've never been comfortable with that. I hardly benchrest my springers anyway.

      BG_Farmer, you don't need a .22LR to do weird science. As a matter of fact, the question about the effect of wind on a bullet at different distances is so rational that I did the math. It's not difficult with some simplifying assumptions. Imagine two cases. In the first, wind is blowing at a constant rate at right angles to the line of fire across a 10 yard stretch in front of the muzzle. In the second case, everything is the same except that the 10 yard stretch is in front of the target at 1000 yards. I'll use Nancy Tompkins's numbers of a 155 grain bullet at a muzzle velocity of 3000 fps and velocity at the target of 1300 fps. There must be some way to calculate the effect of the wind and compare.

      I was thinking in advance that the only way that Tompkins and Tubb could both be right is if the various countervailing factors canceled each other out so that there was no difference.

      The time to cross the 10 yard stretch of wind is

      x = vt

      where x is 10 yards, v is the bullet velocity and t is the time. The deflection from point of aim is

      y = .5at^2

      where y is the deflection, a is the acceleration caused by the wind force and t is time. Combining these by eliminating t gives you an expression for y in terms of things you know.

      y can be used to find the deflection on the target. For the muzzle velocity case it is

      target deflection = (1000/x)y

      the usual minute of angle calculation. Then you compare the deflections caused by wind at the muzzle and wind at the target by taking a ratio and presto. My answer is that the muzzle wind causes greater deviation by a factor of 20! The verdict is decisively in favor of Tubb.

      The difference seems high, but I don't see that I made a mistake. Of course this is a simplified situation, but you would think any complications like Jane's Magnus Force and so on, applying equally to two cases would cancel each other out.

      This raises the more bizarre question of how Nancy Tompkins being a specialist in 1000 yard shooting unlike Tubb who is more of a highpower specialist shooting from 300-600 yards can be so far off. How do I break the news to her? :-) My only other thought is that perhaps complications about angle and variability of wind reduce the differences in my example which, admittedly is an extreme case. When you throw in the fact that different winds are usually closer together than the ends of a 1000 yard course, differences get erased further until maybe you come back to my starting point that with so many things going on, the distance the wind is operating at does not matter much. However, when in doubt, go for the wind that is closest. Wayne, maybe this will give you a leg up.

      Purchawk, I don't see how your friends with the Anschutz rifles could be shooting that much less than MOA at 100 yards. There isn't much room left to go. David Tubb says that some friend of his at the elite level can shoot the $5000 state of the art Tubb rifle .3 and .4 MOA at 100 yards on a regular basis. For anyone less than a professional shooter using a smallbore rifle costing half that much to go under .5 MOA seems very unlikely. That would be just as good as the TUBB rifle. I think going sub MOA with any rimfire on a regular basis would be very good.

      Matt61


    11. Lukus posted this to an older topic, but I am re-posting it here, so everybody will see it.

      B.B.

      Well this question is going off topic, but… A month or two ago I was going back through a bunch of these articles, and someone mentioned a source for .20 cal lead balls. Try as I might, I can't find it again. I believe the source sold the lead balls by the pound.

      I have a Sheridan that I'd really like to try lead ball in. Partly because I'll be teaching my son to use a "grown up" air rifle and the ball would be easier.

      Lukus


    12. Stingray ,

      I am currently testing a production Edge. The gun is due to be shipped in a couple weeks. There have been a thousand little details, but now they are just awaiting the arrival of the foam for the boxes and the first batch of guns will be out the door. I was told by AirForce today that they expect to ship some guns the week after next.

      B.B.


    13. Mike,
      I like the rest and its the first attempt I remember seeing to tailor a rest to the peculiarities of a springer. I'm building a 10m setup in my barn, so maybe if I add a bench I'll use your idea. I have everything (my wife regularly picks up duct tape at the store, just because she knows I'll be needing it).

      BB,
      I don't think the acetone would have been the problem, but the Ballistol might not have provided a tight barrier. Try some 30W oil — it works great for keeping rust off exterior metal. Failure can be more educational than success.

      Matt,
      Your calculations are exactly what I was alluding to when I sided with Tubb. On the other hand, Tompkins isn't a fly-by-night shooter, so she can't be ignored. Even here, a 1000 yard range is not available:). Perhaps the velocity at very long ranges is significantly slower and effects the BC more?





    14. Matt61,

      Impressive!

      Most FT shooters have feather light "flags" hanging from the ends of their rifle.. surveyors tape is a cheap way.

      The thing to consider in field target shooting is the course is 55 yards and less. Every match I've been to so far in my short time at it, has had winds that change in the short 55 yards!!!

      With canyons, tree rows next to open fields, and match directors that take joy in finding such situations!!! They love to place long targets at the end of a tunnel of trees, so your pellet hits a hidden cross, up or down wind just before the target! The cool part is most of the locals your shooting with will tell you about it.. but that only helps a little… if it happens!

      20fpe is not effected very much compared to 12fpe.

      Your right that steadiness, pellet choice, holdover or click settings, are large factors too….

      ..but with 12fpe, wind is probably the largest factor for most seasoned shooters… that's why the MDs love to set up tough courses… that's usually what separates the top shooters, and produces the winner..

      Paul Cray's performance (109/120) at the nationals in that circle of winds and up and down shots across mini canyons, to me when I had shot my best so far 92/120, seems unmatchable!.. somehow he really understands the wind! .. or he has all the other stuff totally down pat, and only missed the really hard wind shots..

      The winner of the 20fpe harness class Harold Rushton shot 117/120 with USFT #19..

      Paul has won many top events and is a more seasoned shooter that Harold, so the difference between 20fpe with a harness and 12fpe no harness, really makes a big difference…. he might well have "cleaned the course" if he had been shooting 20fpe open class!

      So now compare 1,900fpe and see how tough field target can be!

      Wacky Wayne, MD. Ashland Air Rifle Range


    15. okay, I've gone against my mantra…'don't buy chinese, don't buy chinese'.
      I know it's been irrational, but I've bought too much dollar store junk that has broken before I got it home that I've never been comfortable buying a chinese air rifle.
      But my recent issues with the Nightstalker (having it vent 3 .88gm CO2 cylinders a couple of days ago at cost of $22, plus the fact that it really doesn't do well at near freezing temps, which is about 4 months out of the year where I live), plus my desire to own one 'military style' rifle has led me to order the XS-BP today. Looks a bit like a Steyr 77 AUG bullpup assault rifle. Sidelever, 10 shot repeater and bullpup loading (the loading port is on the stock about where your cheek would go.
      Hope I haven't made a boo-boo.
      Anyone have any experiece with this gun?
      CowBoyStar Dad


    16. Wayne,

      Those wind flags on the muzzle seem to be vindicated. Get yours mounted, and it should allow you to largely discount the bushes, trees, and what not. Otherwise, I seem to recall a discussion many moons ago that 55 yards in airgunning is comparable to long range shooting with centerfire rifles, so maybe the highpower wind reading methods apply.

      BG_Farmer, Nancy Tompkins is a super authority from everything I've read and is obviously able to get her shots on target which is why I'm so puzzled. She herself gave the velocity at 1000 yards as 1300 fps. And I thought that BC applied only to cutting the wind in the forward direction, not on the effect of a right angle wind. Still highly puzzling. But at least at 25 yards offhand, it shouldn't matter. >:-)

      Matt61


    17. B.B.

      Ouch!

      You would have totally forgotten about selling the colt to your friend all those years ago..

      ..but now that he's reminded you..

      I'd write him back and thank him for his offer to split the difference between $150 and $3,000… (oh you didn't offer.. I must have misheard you)

      …or if he prefers he could send you $1,500 for using it all these years:) ..

      ..that's what friend are for!

      Wacky Wayne, MD, Ashland Air Rifle Range


    18. Wayne,

      Yeah, that was a finger in the eye. It got me thinking about the other 8 original single actions (not all Colts, of course. One was an 1975 Remington) that I went through in my imprudent youth.

      And people think that a college education is expensive! When I think about what life has taught me and what it cost…

      I have to laugh to keep from crying.

      B.B.


    19. Matt,
      I think the BC applies to wind from any direction, at least to some degree, but I don't know if the BC's contribution to wind effects changes with velocity in the same way. 1300 fps is getting close to the deadly transonic region, where wind effects are magnified also, if my understanding is correct.


    20. Matt,
      I forgot: I think for 25 yards offhand we are pretty equally matched if you are using the B30. If its the .223, you might have a slight advantage bucking the wind over my patched lead balls:). By the way, use whichever you want. I also wonder what the BC of the lubed patch is — some of them go 10 yards:).


    21. The projectile's flight time *and* BC play a role in the movement of the projectile off course.

      In practice wind isn't linear across the flight and it isn't constant. It also blows from different angles. The most significant is the wind earlier in the flight because a small shift is magnified down range.

      Grab a ballistics calculator like this free one to assess wind, elevation of shot, and more.

      http://sourceforge.net/projects/balcomp/

      Its interesting to see what your pellet gun or firearm will do from a tree blind (or second floor) compared to a level shot at the range sighting in.

      You can reverse engineer a manufacture's firearm projectile BC by plugging in their zero range, muzzle velocity, and adjusting the BC until it matches.

      G.


    22. Blue it

      I have the Blue Wonder in my hands ready to leave the sporting goods store when I notice the 44/40. I remember that via mail order an extra $17.00 hazardous material fee is required and the product is only $11.99. For a moment I consider buying both, but the Blue Wonder seems available almost everywhere therefore I go with the rarer 44/40. (I have no idea what the numbers stand for)

      The directions seem straight forward: degrease, wipe on and then wipe off, top with oil. I got this. I put the Walther 55 in a gun holder and use Beeman cleaner degreaser on the barrel. I take a Q-tip dip it in the 44/40 and when I touch it to the bare metal, complements of an angle grinder, the magic happens. Instant black. Wow. I was planning on just touching up the bare spots, nicks and grinder damage but it gets good to me. I take the Q-tips and go crazy on the whole barrel. It sits for a minute while I hunt down a rag to wipe it with. I picture myself as a guest on American Airgunner, the masses line up with worn rifles and like a faith healer I cure each case of bad metal. I have that feeling you get when a trophy size fish reaches the side of the boat and all the worry fades away. But its short lived, as the Walther dries the streaking is terrible. I quickly grab some Rem-oil hoping it will rub out. No chance. It looks worse than when I started. Strike one.

      I re-read the directions. Wipe on and wipe off instantly. It would appear instantly is the key. Whoops. I have no choice but to grab some oil and steel wool and rub the barrel down. I take it to almost bare metal all over and then degrease again. On this second attempt I also heat the barrel first with a Wagner paint stripping gun as I recall B.B. heated his first. I forgo the Q-tips in favor of a larger rag to hit the barrel all at once. Wax on wax off. That quickly I put two coats on wiping any excess as hard and quick as possible. I use Break Free for the oil rub instantly afterwards, once again recalling today’s article. The result is nice and even but thin. Picture a Winchester 94 that is about 75 years old. Fine if I wanted to restore an older worn piece, but it is not what I want. Still, I would say I hit a double.

      Same procedure as above is repeated except no sanding and this time I finish the barrel with a blast of WD-40. Nice. I will have to see how it lasts, and I may try a third coat in a few days, but it looks good. I peek out the windows to see if the line has started… I scored a run.

      Volvo


    23. RE: Colt Revolver

      Ever watch "Antique Roadshow" on PBS? The "provenance" of a item is everything. the other collector is just seeing how far back he can trace the gun's history, he isn't trying to stick a finger in anyone's eye. A grand slam home run would be if he could trace the gun back to the original purchaser's family. He'd have to be very lucky to so so, but how else will he find out if he doesn't ask how you got the gun?

      Herb


    24. Herb,

      The way you do that is by saying, "I'm trying to trace the provenance. Do you remember who sold it to you?"

      I'm sure Tom's friend was delighted to have gotten such a good deal. Tom almost always gets good deals, so maybe now it's his turn to find out what it's like for the other half.

      Edith


    25. Volvo,
      You're getting started the way I did — "oops, I can fix that, then as long as I'm at it…". Most of the time it works out OK, although I still have one riding lawnmower in the queue (since 2007?):).

      I think you would have been OK the first time if you had just done a couple more coats, but once you oil (and/or rub too much) most cold blues are done:).


    26. Matt 61:

      Good point on the difficulty of shooting under MOA. I have been sort of intimidated by all the serious shooting gear: $300 shooting coats, expensive cuffed slings, shooting gloves, and–most intimidating of all–the really expensive guns with the really expensive diopter sights.


    27. Matt61,I'm good with concepts but not equasions…that being said,I'm curious if you took into account the amount of time the projectile would endure two gusts [of equal force and dimension]one at muzzle and the other at 1000 yards.all other things equal,theres three times the duration at the downrange FPS…right? FrankB


    28. FrankB,
      That's a good point, but it would account for only a little difference by itself. I remember nearly every hunting article and book I read as a kid having some similar blurb about bullets hitting blades of grass — either near the muzzle or near the target. Usually that was an attempt to sell whatever "brushbusting" cartridge they were peddling at the time, but the principle was the same — anglular deflection near the muzzle results in a larger movement of POI than near the target. I'm sure Tompkins is going by real experience (unlike most hunting magazine writers:)), so there may be more subtle factors at work. Perhaps the longer exposure downrange (due to lowered velocity) combined with the bullet's entering the rough transonic zone accounts for it? I'm pretty sure that "supersonic" bullet designs are really bad at low speeds. I would also be curious as to what the spin rate looks like at 1000 yards — it is likely to be higly inappropriate for the velocity and weight at that range, but I don't know whether it would be too high or too low:).


    29. If I may, I'll support the assesment of fellow female shooter Nancy Tompkins….

      The effect of a crosswind is more important downrange than at the muzzle.

      Let's put away the BC and trajectory calculators for a moment, (you need to select the correct equations before you start plugging numbers into them).

      Thought Experiment:

      Let's shoot a "perfect pistol" at a 1000 yard target. Our pistol shoots round balls, not bullets, and hits its mark every time. Our range is indoors, but we have two "superfans" creating a crosswind, one is 10 yards out, one is 990 yards out. The ball is not spinning as it exits the muzzle, (no Magnus effect)

      Everyone agree that the amount of deflection is proportionate to:
      1 Wind speed.
      2 Cross-sectional area of the ball.
      3 Time in the breeze.

      Here's the rub:
      Wind imparts lateral deflection, not angular deflection. Unlike movements of the barrel while the projectile is being launched, the lateral deflection will not be magnified down range. The "invisible wind hand" merely reaches out, and pushes the projectile off its path. It is still travelling perfectly parallel to the original flight path.

      If Fan 1 pushed the ball off its path by 1 inch, it will miss its mark by exactly one inch, (If Fan 2 is off).

      As the ball passes Fan 2, only one of the 3 variables has changed – time in the breeze. The ball is travelling significantly slower, and Fan 2 will have more time to push the ball farther off its course than Fan 1. Fan 2 will push the ball farther off course in direct proportion to the velocity it has lost downrange.

      This would be true for pellets because they slow down so fast.

      Anyway, replacing a round ball with a spinning bullet really changes nothing. Yes, there are differentials in the way the wind hits the bullet, and it will impart a "yaw" vector AND and magnus effect, but there is nothing that is going to change the lateral deflection into angular deflection, (unlike rockets, changing the orientation of a bullet doesn't change its direction), and the defining factor will remain time-in-the-breeze, which is determined by velocity.

      Lots' more to talk about here…

      Best regards,

      Jane


    30. Jane Hanson,

      Nice to hear from you. My mind is having a problem thinking about lateral deflection and angular deflection. Oops, it just made sense to this poor old brain–ok Herb, Matt61, etc. have at it. I'll sit quietly and learn.

      Mr B.



    31. Wow, I was sure Nancy had to be incorrect because I was thinking Angular deflection, then Jane made it rather clear to me what was going on. I have not read Nancy's book so I don't know if she took the time to explain this effect similar to the the way Jane did. Now we have to wonder where David is coming from. Was he thinking
      Angular deflection? I gotta get to the book store before the Christmas hordes.

      Thanks, Jane for that explanation.

      -Chuck


    32. RE: wind at muzzle and wind at target

      I vote that it is an impossible scenario to analyze without a lot of very carefully gathered data. In other words, depending on the controlling factors, and the answer can go either way.

      (1) There is difference about rotational axis perpendicular to wind for a bullet that isn't there for a ball. So a perfect round ball wouldn't change direction, but a bullet could.

      Case 1 – Imagine shooting due north with wind from west.

      (a) A ball might be pushed say 1/4" to east by 10 feet of wind but upon exiting the wind, the ball would starting going due north again.

      (b) However the bullet could "turn" about its axis depending on the aerodynamic characteristics of the bullet. So after going through the 10 feet of wind, then the bullet could (not necessarily would, so it depends on bullet) be going slightly eastward.

      Case 2 – Jane's analysis above

      —-
      Conclusion – Like all such questions "It depends."
      - velocity of wind
      - velocity of projectile
      - moments of inertia of pellet
      - aerodynamic factors of projectile
      - etc, etc, etc …


    33. Time in cross wind exposes the projectile to lateral force.
      F=ma
      v=at=t*F/m
      Lateral velocity is not zero
      Therefore projectile flight after leaving the cross wind can not be parallel to original trajectory.


    34. thanks for the link for the old pic BB… but thats far from clear hehehe… you're surely slim back then huh… thanks again BB..

      Iyonk


    35. An object in motion tends to stay in motion…so you're saying the inertia created by the wind keeps the pellet moving in a lateral direction, which has the same effect as an angular change leaving the barrel, and therefore the pellet doesn't really return to parallel of it original flight but keeps moving farther and farther away from it? Does its gyroscopic property hamper this lateral movement at all?

      -Chuck


    36. Regarding the lateral versus angular displacement, both are simplifications. The bullet will keep moving "sideways" even after it passes through the wind due to inertia, but theres drag in the opposite direction which will eventually stop it from moving laterally. At least I think the bullet will eventually end up being displaced an amount proportionate to the wind force on it and parallel to its original path, not moving out indefinitely. This assumes of course that the wind is only active over a short portion of the trajectory. Even if this is right, it too is an oversimplification:).



    37. Hi Jane. I'm glad to see that Nancy has allies, and thanks for your clear reformulation of the experiment.

      I have to side with anonymous in taking issue with your claim that once the flying ball is released from the influence of the wind that it will resume a forward flight parallel to the original trajectory. This abuts on a discussion from a long time ago where I objected to claims that a rifle can decrease the MOA of its groups as distance increases. As others have done, I'm invoking Newton's first law. The forwards and lateral movement of the projectile work independently just like the forwards motion and the downwards motion induced by gravity. So once a wind sets the ball into sideways motion it will keep moving. It won't return to the flight path direction without a force in the opposite direction.

      BG_Farmer suggested that wind resistance induced by the sideways motion of the ball may be a force to reduce the lateral motion. However, I seem to remember that wind resistance is proportional to the speed of the projectile. The lateral motion caused by the superfan is so slow that I doubt that the induced wind resistance would stop it–certainly not within a thousand yards, probably not before it hits the ground miles away.

      The observation that this is a hugely complicated situation is correct, but I don't know that all complications are created equal and one can find contours among them. Specifically, complications can reduce the difference between the apparently much greater force of muzzle wind compared to target wind according to my simple calculations. Circumstances can be such that the difference is practically zero. But I don't see any physical reason to support the target wind over the muzzle wind. Other things being equal, it looks like of two equal winds at the muzzle and the target, the muzzle wind will have much greater effect.

      The remaining puzzle is Nancy herself. The woman is a fantastic shooter able to hold a call radius of half a minute of angle at 1000 yards. Perhaps this is the answer. She says that the tighter your hold, the less you will be moved by the wind. That's basically common sense. Maybe her half minute hold has compensated for an error in her wind reading.

      And in my experience, experts can make mistakes, not just outside of their field but even in the heart of it. Perhaps the most extreme example I've seen is from a boxing textbook by an author named Haslitt. This was written during the Golden Age of boxing prior to WWII, and is sort of an encyclopedia of boxing combinations and techniques. There's nothing like it, and Bruce Lee devoured and even plagiarized a good share of it in writing his own martial arts textbook. Anyway, the end of the book has a section about preparing for a fight, and here the author blandly says that the best thing to do is not to drink water for 24 hours before the fight. This, he says, will increase the proportion of electrolytes in your system, and allow you to operate like a charged battery! Crazy! If I tried that I would unable to stand up. How could anyone, let alone an expert, say something like this.

      Maybe it all goes back to the movies. Was it Conan? "Trust no one, my friend, trust no one." >:-)

      Matt61



    38. joeengineer,

      The jeans with lead shot will work well for PCP's and powder burners. However, a springer recoils both backwards and forwards and will not give you a good group unless it's shot with the artillery hold or fired off a very soft rest that doesn't give the gun anything to bounce around on while recoiling.

      Use the search engine and look up artillery hold. It's a very informative read. Let us know how it works for you please.

      Mr B.


    39. Matt61:

      Good to see everyone is awake and on caffeine.

      Strictly speaking, whoever suggested "F=ma..lateral velocity is not zero" was correct. We have bumped the projectile and imparted a lateral acceleration, and newtonian physics tells us this will indeed create angular deflection.

      However, we need to recalculate the opposite vector as soon as the projectile clears the fan. Relativistic physics says it doesn't matter if the air is moving laterally against the bullet, or the bullet is moving laterally against the air. We now have a "correcting vector" that does, indeed, tend to push the bullet back on to a paralel course.

      So much for "thought experiments".
      In the real world, there is wind, and not fans. The bullet in the breeze does indeed alter its path as it is subjected to a crosswind, and the correcting effect is always less than the initial force.

      The overwhelming force, however, will remain time-in-the-breeze, and, particularly at very long ranges where velocity fall-off is significant, down-range wind generally has greater impact…..
      Trying to determine how and when this happens is what I call "job security"

      regards,

      Jane


    40. Isn't it amazing that a rifle can take mere seconds to solve accurately without paying attention to US.{I'm just happy my point was similar to Jane's!!} Frank B


    41. "However, we need to recalculate the opposite vector as soon as the projectile clears the fan. Relativistic physics says it doesn't matter if the air is moving laterally against the bullet, or the bullet is moving laterally against the air. We now have a "correcting vector" that does, indeed, tend to push the bullet back on to a paralel course."

      This would be true iff you reversed the fan for the proper amount of time.


    42. the fact is we can easily create a controlled experiment!!!using a fan,an adjustable velocity airgun{properly zeroed,of course}a 10 meter lane indoors,and shoot at two velocities that mimic muzzle and downrange velocities.the first velocity needs to be approx. 3X the second to simulate Matt61's original model. Frank B


    43. Anonymous,
      You don't have to reverse the fan. The pellet is moving laterally through air at the same rate imparted to it by the wind (original fan), thus there is a force, equivalent to a wind in the opposite direction slowing (and possibly stopping) the pellet's lateral movement.


    44. BG_Farmer
      Velocity is a vector. After the air drag has stopped lateral movement to zero, the vector direction has still been changed. It ain't parallel anymore.



    45. Anonymous (got a better handle?),

      The direction component for the projectile's velocity is simply translated, if I can say it that way; the projectile doesn't get pointed (or just as importantly propelled) in a different direction (one of the reasons Jane used balls in her thought experiment, I bet), being always parallel to the original.

      Regarding the ricochet, in that case the direction is obviously changed, since a projectile can't hit a surface parallel with its path, and the projectile moves off with a new speed and direction, i.e. a different vector.

      I could be wrong, but that's what I think–currently:). Jane really nailed it when she characterized the displacement as lateral rather than angular.


    46. Forces act upon the projectile, be they a rock or a fan. When the forces are gone, they're gone, but the influence remains. The vector direction is altered. Basic physics it seems to me. Forces do not act upon the projectile as you envision, which seems to be analogous to sliding a paper underneath the bullet's path.

      Anyhow, I'm off to a week's cruise to the mexican riviera, so I'll leave this discussion to better minds than mine.


    47. Yeah… wind will change the direction of a pellet so that the further it travels the more POI will shift.

      Think of a pool table and a ball that kisses another it does not just move over a bit and keep going. It actually changes direction. Same thing.

      You could set up a fan based experiment to prove wind effect will affect the direction of travel. Set up a hair blow dryer then role a ball past it and observe. If the table is level you should be able to trust the results.

      DB


    48. BG_Farmer and anonymous,

      How about this? BG_Farmer, you're right in that once the ball's lateral motion is stopped by sideways wind resistance, then it will resume a parallel path since the only remaining component of motion is forward. However, until this happens, anonymous is right in that that the motion of the ball is the vector sum of the forward component and the lateral component, and this will apply after the initial force (lateral wind) has been removed.

      Jane, I don't even drink caffeine. :-)

      Those are good experimental ideas. I think the one with the hair dryer is actually doable.

      In other news, I believe I'm evolving towards the "surprise break" trigger release which I had resisted before. From my new experience, I think the surprise break is not exactly a surprise. It's more like disabling the conscious mind and giving the subconscious a chance to work. That would explain how one can know and not know when the trigger releases as B.B. described. It's different levels of awareness operating.

      For instance, the double-action trigger on my Walther Nighthawk is so abominable that controlling it is just about impossible. I've taken to pinning the sights on target then pressing the trigger through, come what may, until the shot. More often than not, the shot is not bad. And when I really follow this procedure, accuracy is surprisingly good.

      I'm down on the Mosin-Nagant after more reading. It appears the original trials for the rifle were won by Nagant, a Belgian inventor, whose design had been passed over in favor of the 98 Mauser. However, the Russians wanted a homegrown rifle, so they picked the inferior design of Mosin and incorporated the Nagant magazine system. So, the U.S. does not have a monopoly on badly run and rigged weapons procurement. This history places the Mosin-Nagant two steps below the 98 Mauser.

      Matt61


    49. Matt,
      I thought that is what I said originally? I think my clarification wasn't:). The net result is (will tend toward) a parallel path, not a change in angle.

      Anonymous, DB,
      Keep in mind that the force of drag opposing the original force of the wind, while smaller, will continue acting until the projectile stops its "lateral" motion and is, I would think, of similar magnitude to the original wind force. That would be wrong in a vacuum, of course, but wind isn't usually a problem there:).

      In the case of the ricochet (and the pool ball), the same thing will happen, but the force of the drag is relatively small relative to the change in direction.

      Is that better?


    50. RE: parallel path or change in angle

      The reason Jane used a round ball was because a ball can't be "turned."

      But a bullet or a pellet can be turned by the wind.

      Think of a weather vane made using a ball and one made using an arrow. So if the projectile turns or not depends on the aerodynamics of the projectile. There are just too many factors for a pat answer.


    51. Herb,
      RE: "There are just too many factors for a pat answer."

      Amen:). I originally though that Tubb was right and that angular deflection (which DB and Anon. are essentially arguing) was the correct analysis, but Jane's thought experiment and insistence on lateral displacement in support of Tompkins made me rethink that, in the course of formulating arguments against her position:).


    52. If anon. was correct, a slight change near the muzzle would put the shot so far off [if the vector DID change] firearms and airguns would be as controllable as roulette wheels,and nobody would use them…think about what you can do at 25 yards,then think where it would go if the muzzle moved 1".that is what your suggesting that wind does! you are ignoring inertia.


    53. If you search"doping for wind"on youtube,a couple very good videos come up…one suggests the first 300 yds are 70% of the total wind effect…some good illustration of reading mirage and foliage as well.Very informative 3 minuite video!!! Frank B




    54. BG_Farmer,

      I was thinking in terms of 3 phases for the sideways motion. Phase 1 under the influence of the wind has the ball accelerating sideways. Phase 2 after the wind has stopped has the ball still moving in a way that approximates a constant velocity (inertia) but is really a slow deceleration because of induced wind resistance. Phase 3 is when wind resistance has stopped the sideways motion of the ball and it is going forward. I understood your model as corresponding to phase 3 and anonymous with phase 2. You're right that the ball tends to return to a parallel path but not right away and certainly not as soon as the wind stops acting.

      I don't see the angular displacement versus the lateral displacement being a real distinction but rather alternative representations of the same thing. The basic trigonometry formula is

      y = rsine(theta)

      where, in our case, y is the lateral displacement, r is the distance from the muzzle to the projectile, and theta is the angle between the flight path and the point of aim. You can describe your quantity as y or theta but it's the same thing.

      Regarding the turning of the bullet/pellet, it is a theoretical possibility, but if the wind was truly sideways, as in our example, there's no reason for the bullet to turn. Even if it did, it wouldn't necessarily change things. Jane showed some time ago that a pellet travels slightly nose up relative to a flight path but this attitude and some degree of precession that might result don't necessarily move the bullet off target (via a corkscrew trajectory).

      Yes, things are complicated but there are still simple problems that demand to be solved. To look down a long range and see two flags at different distances with the same magnitude but opposite directions is not an implausible scenario. So, as quarterback Vince Young said in a memorable Cotton Bowl game of several years ago, "Watcha gonna do?" (I think he was facing 4th and 2 with no time outs late in the game.) Say it's too complicated? Practicing shooters face this problem all the time so surely there's something useful that math and science can contribute here without explaining everything.

      Speaking of practical things, BG_Farmer, it looks like I won't make it to the range this month between traveling obligations and some other things. December 12 is my new target date. Definitely before Christmas!

      Matt61


    55. Matt,

      That's exactly the way I envisioned it. I agree that displacement versus deflection is a "nice" distinction — my only real point was that there is a limit on the deflection of the projectile from the early wind, otherwise Tubb's (conventional) view is the clear winner (and certainly easier to visualize), at the expense of dismissing Tomkins' experience.

      Don't worry about the range time, whenever you get to it will be fine — there's no money at stake (I hope!). I might pull a fast one and update my targets if I get better, though:).


    56. sorry for off-topic but, I just moved to Dallas and would like to know good place for airgunning. I would be thank full if some one can point me to places to buy and a good range.


    57. Herb: Please tell me why a round ball can't be turned by the wind?? Of course it can, the same as any other body in motion.

      To all the parallel path proponents, please understand that yes, indeed!, lateral motion will eventually halt due to air resistance – at __PRECISELY__ the same instant forward motion halts.

      Wind changes the vector direction. There is no other correct answer.


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