Mop Handle Slingshot Rifle with Quick Change Barrel

Discussion in 'Show off your homemades!' started by Darcy, May 5, 2020.

  1. Yes, I like it.

    4 vote(s)
    100.0%
  2. Indifferent.

    0 vote(s)
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  3. No, doesn't appeal to me.

    0 vote(s)
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  1. Darcy

    Darcy New Member

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    Hi all,

    This is my first attempt to post to the Slingshot Channel Forum (or any forum). I am 70-year old technologically challenged male who was not forced to use a computer until late in life, so I’m hoping I don’t screw this up.

    In the spring of 2019. I happened upon one of Joerg Sprave’s slingshot videos and ended up watching a bunch of them. That brought back memories of making my own slingshots way back when I was kid growing up in a small town in southeast Kansas, USA.

    Joerg’s creative genius inspired me to make a contraption I call the Vermin Popper, a cheap slingshot rifle made mostly from scrap metal from my good friend and landlord’s basement, some cheap wood and an old mop handle she gave to me after another friend accidentally stepped on the mop head and broke it. I will attempt to post some photos of the rifle and its fold-up stand to illustrate what I am writing here. Please “let me show you its features.”

    1. The mop handle “barrel” features easily adjustable length. You can push the small silver spring buttons to easily add or subtract 1-foot sections of the barrel in 10 seconds or less. This also makes it possible to easily shorten the overall length to haul it in the car, or, to easily attach a different fork with a different band set in seconds. I plan to use this rifle as my “research and development” model, so making it easy and fast to switch barrels, forks and band sets works for me.

    2. It has a simple trigger/release mechanism similar to one I saw in one of Joerg’s videos and like some others I saw on Chinese slingshot rifles on the Internet. I made mine with a thumb trigger that I like because it is simple and reliable (and I currently have a problem with swollen joints in four of my fingers).

    3. The Vermin Popper can be loaded by placing a ball (I shoot 10 mm steel and 36 cal. lead musket balls) in the pouch and then placing the pouch between the two tongs of the trigger/release; the pouch and shot will stay in place (without holding it) under very little band tension until I am ready to cock the rifle.

    4. When using the full-length barrel, I cock the Vermin Popper by first setting the pouch (holding the ball) in the trigger/release mechanism, setting the stock on my left boot while kneeling on my right knee (or while sitting), grasping the small thin plywood grip attached to the end of the draw cords (Paracord), pulling the grip down toward the midsection of the rifle, and hooking the grip to one of the two chrome bolt extensions protruding from the underside of the rifle (I threaded the inside of the chrome extensions to go over ¼-20 threads). There is a hole in the plywood grip handle that allows hooking it to the chrome bolt extensions. I can cock the rifle while riding in a small row boat without standing up (hope to try duck hunting).

    5. You can draw the bands to a partially cocked length by hooking the grip to the first chrome bolt extension (to increase band life during indoor target shooting in the basement) or draw the bands to full stretch (ratio is about 5.3 to 1 with the 69-inch barrel) for hunting or longer shots. You can also make smaller incremental adjustments in band stretch by simply changing the length of the draw cords (I untie and retie the knot at the end of the cords).

    6. The mop handle barrel is relatively light as it needs to be because of the leverage factor with the longest barrel length. My current forks are made of cheap PVC joints that I bolted together (to ensure no sudden turns or pop-outs), a couple of cheap 1/4-inch diameter bolts with small (44-pound limit) pivoting pulleys at the fork tips, and a triangular fork support made of thin plywood.

    Please note: I use small rubber bands to keep the pivoting pulleys from swinging inward (and out the line between the tongs and forks). The rifle is designed to keep the stress under full band tension as close to parallel to the barrel as possible. I’ve tested it up to a 45-lb. pull of band tension but my best bands pull about 27 to 31 pounds. I’m sure the very light barrel will not stand much force perpendicular to its length. I’ve shot it about 600 times without any sign of bending or cracking – so far, it’s been promising.

    7. The rifle has a relatively inexpensive adjustable red-dot sight (made for Daisy air rifles) attached with my homemade aluminum mount.

    8. The wood frame and stock are made from Poplar, I haven’t bothered to stain or paint the wood because I may be making more changes to it.

    9. Total weight with the longest barrel (with all extensions) is exactly 6.0 pounds and the rifle's overall length is 69 inches You can easily break it down into two sections by detaching the barrel in about two seconds. The longest section measures 37 ½ inches.

    10. Performance testing. The following test results were obtained with a Chrony using the two fastest shooting band sets I have made and tested thus far. Both of these tapered band sets were made from new Thera Band Gold. I shot steel on eight consecutive shots on one day and lead on eight consecutive shots a couple of days later with the second band set. These test shots were all indoors (still air) with 68 - 70 degree Fahrenheit room temperatures. There was an interval of five to nine seconds from beginning to cock, taking aim and firing, across all test shots.

    a. 10.30 mm diameter steel balls – fastest shot with a full draw was 309.6 feet/second, average was 306.13 feet/second across eight consecutive shots

    b. 36 cal. Hornady lead musket balls – fastest shot was 300.1 feet/second; average was 296.65 feet/second across eight shots; these were all shot with the bands about one inch short of a full draw. A single lead shot fired about one week (and 80+ shots) later with a full draw had the lead ball registering 302.2 feet/second (my fastest for lead).

    c. Accuracy – better than I expected for shaky me; with the air rifle sight dialed in I have hit the soup can on 20/20 consecutive shots from 30 feet (that’s as far as I can get from the target in the basement).

    So far, I haven’t killed anything but soup cans but it’s great fun to shoot at them hanging from a string until the bottom half of the can falls off. If we end up having a food shortage with the COVID-19 pandemic I may try using the rifle to put some meat on the table this fall. If anyone new to slingshots tries making one of these from a mop handle (or anything else) please be safe (e.g., wear googles, start with light bands and plastic practice ammo, check to see if anything is coming apart before each shot, etc.). I would like to say THANKS to Joerg for the inspiration, all of the great video’s and for giving me a new hobby that I can have some fun with in the basement while I’m finishing college.

    Darcy

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    Last edited: May 20, 2020 at 6:49 PM
    Cremantus and Bugar like this.
  2. wellslung

    wellslung New Member

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    Thats cool, looks very intricate but a lot of fun.
     

  3. P.Konrad

    P.Konrad New Member

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    Those Chronograph results are very nice indeed. You saved yourself alot of coin doing it yourself. Check this guys home made out. Super Slingshot Rifle ( homemade ) , testing . Stay safe, regards PK
    p.s Excellent first post.
     
    Last edited: May 7, 2020
    Darcy likes this.
  4. Bundaboy

    Bundaboy New Member

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    Great post, well built, solid looking unit.
     
  5. Darcy

    Darcy New Member

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    Thanks for the comment and the video; wish I spoke the builder’s language. He made a very nice foot-cock shooter. The only tube bands I’ve tried are for the orange Barnett Cobra and Black Widow; I used those for baseline. I ended up overstretching them and then tried the flat bands and had better luck; more projectile speed and lighter draw. I want to test a couple more Thera Band sets and then I would like to try using two to four per side small diameter tubular bands like those I see on the Internet. I have some ideas for making a more powerful inexpensive slingshot rifle but that may have to wait until I finish school, hopefully by fall.
     
  6. Darcy

    Darcy New Member

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    Thanks for the comment.
     
  7. P.Konrad

    P.Konrad New Member

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    Not a problem mate. A picture says a thousand words aye. Your Chronograph results are vey good, My draw length is shorter and might only get 280fps with 12mm lead (0.472441 inch).700mm (27.5591 inch draw) factory says 6mm steel 350 fps. There is a band calculator to help (google) slingshotchannel.com/band_calc.
    I am searching for the perfect bands for my ammo also. I am waiting for a Chronograph to arrive. Pics of my rig.

    [​IMG]
    [​IMG]


    Kindest regards PK.
     
    Last edited: May 8, 2020
  8. Darcy

    Darcy New Member

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    Hey PK, I watched several videos on marketed slingshot rifles last summer. I liked the Flymar best all-around and I’m still thinking about buying one of those. I used Joerg’s band calculator and some info from other videos (including Pocket Predator’s) to come up with some band set dimensions I wanted to test. I’ve tested some that I don’t think are ideal, but testing (with a chronometer) is knowing and makes comparisons much more objective. I made myself a data form to keep track of what I have tested and I’m making plastic templates (that I cut out with scissors) so I can accurately replicate band sets. I’ve been trying to decide on best ammo for ducks. I hope to take one in flight so I’m thinking I should go for smaller diameter and heavier (i.e., lead) ammo with a lot of penetration, but there are a lot of places around here where you can’t use lead. I found one video (Catty Shack Hunter, Catapult/Slingshot Ammo of Choice) by a guy in the UK who has apparently tried a variety lead and steel ammo sizes for ducks, pheasants and other small game. He draws his slingshot back to his cheek and his favorites were 10 mm lead and 11 mm steel which he thought were comparable. If your Flymar will shoot 12 mm lead at 280 fps I think that would be pretty good impact. I found some helpful answers to questions about what works for hunting on the Pocket Preditor forum in the Q & A; I haven't yet explored the hunter's section here. What game would you hunt in your area?
     
  9. P.Konrad

    P.Konrad New Member

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    To take a duck on the wing is a cracking shot, most do it with a shotgun. Lead is banned in many places now.

    There are no lead restrictions in Australia and I live in a target rich environment
    (4 acres with my parents) I am 44 (divorced no kids), I can walk out my back door and within ten yards,

    There are rabbit's and the occassional duck, Indian mynar and starlings (vermin bird here) (Foxes and Feral cats with the Bow). I have watched that Catty Shack vid many times,

    Joerg Sprave has a video of the correct mixture and process for the gel.

    I have molds for 8,10,12mm. 8mm, bird round, 10mm, all rounder and 12mm for the thud. I think I have a sinker mold that is 16mm too. A video of a Home made ammo tumbler

    slingshotforum.com is a bigger forum with alot of info there too. Gamekeeper John and joefe slingshot hunting are some others also. Yeah mate I am a Utube subscriber to nearly all of them. I think I will try 3/side Therband black/blue 50mm to 10mm tapper for the 12mm.

    Another band calculator:
    Rubber Band Calculator - for Slingshots

    This one says I will get (262fps, 8mm lead + 0.2 (52.4fps) for the type of anchor = 314fps) Theraband gold

    Here is Torstens vid (430fps) bands


    Here is my thread and question with pictures of my complete rig on the other forum.
    https://slingshotforum.com/topic/12...ars-a-hunting-slingshot-rifle-with-12mm-lead/

    Very nice to talk catapaults to someone. PK.
     
    Last edited: May 13, 2020
  10. Darcy

    Darcy New Member

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  11. Darcy

    Darcy New Member

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    THANKS PK, for all of the info and videos; very useful information. I'll see if I can find my way into the other forum you mentioned. Guess I need to make a tumbler; glad I saved my nicked and damaged lead musket balls. I haven't been able to get the downloaded Thorsten band calculator to work as yet and I think that may have to do with my computer; I plan to come back to it. I watched the "430 fps" video and am going to see if I can use some of those numbers (for the 10 mm steel) when I cut some new bands for my HTS frame. I did not see in that video what the draw length or stretch ratio was. I am guessing the draw to be between 52 and 56 inches. I also noticed that those blue rubber sheets appeared to have a very uniform thickness. My TheraBand Gold 5-inch wide rolls are thinner on one edge than the other. I was wondering if you or others have found that to be true with the Gold. Getting a duck in flight might be a bit ambitious but, when I was a lot younger, I took a couple of pigeons in flight with a bow so I think I might be able to do it if I practice enough on thrown targets. I would be very interested to see what numbers you get with the Flymar when your chronometer arrives. Have a good one.
     
  12. P.Konrad

    P.Konrad New Member

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    G'day Darcy,
    Champion, sorry for throwing you in the deep end on that one. That band calulator is a xcel spreadsheet. You need to download and install open office https://www.openoffice.org/download/. If it is too much to work out stick to Jörg's http://www.slingshotchannel.com/band_calc.html
    as a reference, Chrony and tinker as I need too also.

    I can only speak for my rifle about band length, I measure from the forks to the release where the pouch goes, this is 700mm (27.5591/ inches) and add 30-40mm for pouch tying and connecting to the forks.

    I have read and watched on Youtube that I will divide 700mm by 5.5 or 6 (max) add the extra (30 or 40mm) for the pouch and fork tying in. 700 / 5.5 = 127.27mm. Therefor I will cut my bands at 127 + 30 = 157mm 15.7 cm or 6.1811 inches. I only use mine as and example (please use this example with caution) as your unorthodox system is unfarmiliar to me. Try to stick to 5.5. Don't stretch more than 5.5 - 6 times of the unstretched length.

    I am not sure about an uneven thickness. You will have to use your better judment. He is using Theraband Blue/ Black. Thinner, retracts faster but shorter band life, you use more multiple bands with heavier shot, single bands don't throw a heavy shot efficiently (I have not seen many people use it for 12mm lead). Speed freaks on slingshot forum has a Hall of fame for a 300 fps club. You will find greater details there.
    https://slingshotforum.com/topic/19722-speed-freaks-ssf-300-club/

    Most of the community uses a rotary cutter and a self healing mat to cut flatbands (nicks in the cut cause band failure) (careful). I have pouch material, pouch cutting dies and a band making jig coming from GZK (China). Alot of people say that Kangaroo leather is the best.

    As for tappering, this is determined by the type of shot and band length which is shown by the calculator.

    Shooting birds on the wing, I congratulate and applaude this achievment. I believe you, I have seen it done by Tim Wells and co
    https://www.youtube.com/user/worldhuntinggroup/videos
    Amazing Marksmanship.

    Goodstuff mate, I love talking sling shots and sharing the little that I know. I have only been shooting for a couple of months and I am waiting for stuff to arrive (scope rings etc) COV-19 shut everything down in China for a couple of months.

    If you have any questions or wish to enlighten me about any sling shot stuff send me a personal message or write it here and I will do my best to point you in the write direction. The advice I give I use myself. Please join the other forum, nice people there too. Jörg use to post there also. They know there stuff there too. https://slingshotforum.com/

    They are not big fans of hunting on this forum, If you shoot anything post it here https://slingshotforum.com/forum/23-slingshot-hunting/ on this forum. I guess they let us have our conversation because our dicussion was more about perfomance than hunting (we didn't post any graphic pics).

    Kindest regards PK.
     
    Last edited: May 12, 2020
  13. Cremantus

    Cremantus New Member

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    Thumbs up, man! That is a nice piece of work.
     
  14. pasquale

    pasquale Member

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    Wow your contraption looks like it was very much work. Good Job
     
    Darcy likes this.
  15. Darcy

    Darcy New Member

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    It was a bit of work but I've had a lot of fun shooting it and trying different homemade band sets and ammo. I think I'm learning a lot from this project. Thanks for the interest.