Testing Chinese Tubes

147963 Views 346 Replies 72 Participants Last post by 202, 7 mo ago

Henry the Hermit

Discussion Starter · Dec 24, 2011

I've owned a Dankung Jungle Hunter II for more than a year. Right up front, I'll say I don't like the Dankung, but I do like the thin Chinese tubes. I plan to test a variety of configurations, and will use the Dankung because of the ease of changing tubes. To kick things off, here are the results I got from the original OEM bandset, which I assume were 1745.

Pull weight at 30 inches - 19 pounds
Velocity -
.375 lead ball (75 grains) - 192 fps avg 5 shots
.429 lead ball (115) grains - 182 fps avg 5 shots
.495 lead ball (175 grains) - 161 fps avg 5 shots
Note: all measurements were made with my computer and Audacity. Later I will compare the computer measurements against my Chrony.
* Velocity measured at my normal 34 inches draw.

Further testing will be with 1842 because that is what I have.

Now I'm going outside to make some Chrony measurements.

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241 - 260 of 347 Posts

Henry the Hermit

Discussion Starter · #241 · Mar 17, 2013

I'm not sure what you consider useful speed, but I shot 280 fps with pseudo taper 1842 and 3/8 steel. What speed are you getting with the triple tubes?

jokso

· #242 · Mar 17, 2013 (Edited by Moderator)

Somewhere around 200 fps, measured in audacity, didn't measure pseudo but it was waay slower....I know I'm doing something wrong but what?I also got fingers slapped each time with pseudo

Knotty said:
Of course pulling harder doesn't always guarantee the speed increase expected because of the way elastics operate.

I learned that hard way, when I got therabend silver tubes...it must meant to be welded by a terminator, it was heavy like a scuba spear gun bands. And when I shot it speed was slower than normal tubes

Reactions: 1

Henry the Hermit

Discussion Starter · #243 · Mar 17, 2013

jokso said:
Somewhere around 200 fps, measured in audacity, didn't measure pseudo but it was waay slower....I know I'm doing something wrong but what? I also got fingers slapped each time with pseudo

Audacity can be tricky to interpret, but if you are getting consistent readings, you are probably doing it right. You should be getting over 200 fps with the 3-tube slingshot and .50 cal lead. That setup screams for heavy ammo.

Just looking at your rigs, I believe a big part of your problem is the thick, heavy pouch. The handslap with pseudo comes mostly from the heavy pouch. There are several Vendors here who can fix you up with strong, lightweight pouches.

Just don't quit. I'd like to see your name in the SSF 300 Club.

jokso

· #244 · Mar 17, 2013 (Edited by Moderator)

Thats the pouch i salvaged from marksman tubes

If any vendor has reasonable shipping costs to Europe I'll try light pouches.

Dont have access to heavy ammo, 3/8 steel and 8.5mm(00 buckshot) lead is my choice so I have to build on that. And 250-280 fps with it is very useful.

What about this pouch -
Non magnetic- Performance size; 68mm long (2 11/16 in.)
5/8 with 5.0 mm (3/16) center hole?

Henry the Hermit

Discussion Starter · #245 · Mar 19, 2013

jokso said:
Thats the pouch i salvaged from marksman tubes If any vendor has reasonable shipping costs to Europe I'll try light pouches. Dont have access to heavy ammo, 3/8 steel and 8.5mm(00 buckshot) lead is my choice so I have to build on that. And 250-280 fps with it is very useful. What about this pouch - Non magnetic- Performance size; 68mm long (2 11/16 in.) 5/8 with 5.0 mm (3/16) center hole?

That pouch should work fine if it's not too thick. Most of the pouches I use weigh 1.5 grams or less. For speed shooting, I use home-made pouches that weigh about .5 gram. For power shooting, I use my home-made pouches made from fairly thick leather. They measure 3x1 inches and weigh about 3.0 grams.

Look through our Vendors and send them PMs telling them what you want. Most of them will ship to Europe.

jokso

· #246 · Mar 19, 2013 (Edited by Moderator)

Ok thanks

jokso

· #247 · Mar 25, 2013

1842 is here!
First tried single pseudo, visually was slow so I didn't bother to measure speed. Then, double looped, visually very very fast but too hard too pull, aiming is very hard so again didn't measure it.
Finally double pseudo, pull was just right, not to hard not too low....readings were consistent 228-230fps, with 8.5mm lead

Gas Wire Gadget Bicycle handlebar Audio equipment

You can see the piece of tube used for tying, on the fork side 2 x triple folded, pouch side 1 x triple folded

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pgandy

· #248 · Mar 25, 2013

What overall length is your band, what ratio did you use, and finally what is your draw length? If you don't mind me asking.

Northerner

· #249 · Mar 25, 2013

I have single 1842s on my little Bat frame. The tubes measure 5.5" from fork to pouch. Pouch is 2 3/4" long. Draw length 32". Velocity is 203 fps with 3/8" steel (9.5mm).

Cheers,

Northerner

jokso

· #250 · Mar 26, 2013 (Edited by Moderator)

[ quote name="pgandy" post="270213" timestamp="1364226098"]
What overall length is your band, what ratio did you use, and finally what is your draw length? If you don't mind me asking.[/quote]
Around 14.17 inches overall, ratio you can see on the pic, don't know my draw lenght, once I set the tubes, i just adjusted ratio to match my draw

stej

· #251 · Mar 26, 2013

I see Dankung added more tubes. One of them is 3050 which should be weaker than 1745. Anybody who has Chrony and would like to compare 3050 to others?

Cross section area

1745: 13.6mm^2

3050: 12.6mm^2

halbart

· #252 · Mar 30, 2013

Henry in Panama said:
'pop shot' said:

It will be nice to see some actual tested theories for a change. We've just been wandering through this hobby with no guidance or theories to what to shoot. I use old condoms for bands because I have no idea what I'm doing.

Click to expand...

Don't use the ones you find on the beach. The sand is bad for them.

I think they're pretty good. they've got some grit.

pgandy

· #253 · May 26, 2013

My newest configuration is 1745 tubing cut to 17¼". It pitches a .38 cal. lead ball w/34" draw 182 fps, but the clincher is the life. I retired the first set after 1467 shots. It was still working but power was down about 1 fpe. I am on the second set with over 1500 shots and see no real noticeable power lose. I still use double bands pseudo tapered and a cocktail, but for general shooting that single loop of 1745 working great for me and my pocket book is thanking me.

Stonepark

· #254 · May 27, 2013 (Edited by Moderator)

I think you will find 3050 has a cross section of 16mm2.I use 3050 on my sniper (3 bands per side, 17 cm length for 30 inch draw) and it is definitely stronger.

hoggif

· #255 · May 27, 2013

My spreadsheet as well gives 12.6mm² for 3050.

Dr J

· #256 · May 31, 2013

Thanks for sharing all this useful information. Very much appreciated.

boby

· #257 · Jun 2, 2013

pgandy said:
My newest configuration is 1745 tubing cut to 17¼". It pitches a .38 cal. lead ball w/34" draw 182 fps, but the clincher is the life. I retired the first set after 1467 shots. It was still working but power was down about 1 fpe. I am on the second set with over 1500 shots and see no real noticeable power lose. I still use double bands pseudo tapered and a cocktail, but for general shooting that single loop of 1745 working great for me and my pocket book is thanking me.

Those are great lifetimes. Can you describe your pseudo-taper tie and, if relevant, your fork tie that lets you get so many shots? (What is a "cocktail"?). Also, can you tell me the lengths of the single and doubled sections of your pseudo-taper that had 182 fps. Also, when you say "single loop" of 1745, do you mean a single strand (e.g., tied at fork and pouch), or a single strand folded back and tied only at the pouch, which really acts like two strands? Thanks.

pgandy

· #258 · Jun 2, 2013 (Edited by Moderator)

I think you misread that post and I'll try to address each of your questions with all references using 34" draw and in the first two cases 1745 rubber only.

First the single loop (aka factory style) that is giving me such good life, 1540 shots as of this morning, is one length of rubber cut to 17¼" with both ends tied to the pouch. I just measured the set in use and it is 8" from pouch to fork. There is no fork tie as I use Dankung type catty, I just snap in place making changing a band set a snap, literally. It is that set that I clocked 182 fps w/.38 lead.

Second, the pseudo taper. I pretty much followed Henry's lead using his initial ratio 4:3. That is the loop was 4" long with the pouch an additional 3" away. When he changed to a 1:1 ratio I followed suit. However for me I found the 4:3 gave more power and have gone back to that. And now make them slightly longer although in theory the shorter length would be faster. I now mark the tube at 8.375" and fold the end back to that mark and tie. I increased the single section form first tie to pouch to 3.125". I now use the pseudo tapered bands only in doubles, that is two bands per side. I get an average of averages of 207 fps w/.38 lead. I prefer .50 lead at 181 fps. But by far shoot more 6.8 g hex nuts at 205 fps.

Third, a cocktail is a band set using two different size tubes, one end nested inside the other's end. I use 2050/1745. This gives more power than a single loop but not as long life. And more power and life than a single pseudo band but not as much power as a double set. Perhaps this link will help. http://slingshotforu...e-2#entry253433 Scroll about halfway down to Zwillie. I've been using one loop of 2050 with 1745 inserted in both ends and tied to pouch like in the second method. I am not saying my 2050/1745 is the best. It was all I had to work with and I like it. No doubt there are a better combinations.

http://v.youku.com/v_show/id_XMzY0OTE4MTk2.html

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pgandy

· #259 · Jun 3, 2013

Sorry, for the cocktail I use 2050/1842 AND NOT 2050/1745. The reason being I had a hard time inserting the larger 1745 into the 2050. I think the 2050/1745 would give better performance and better life. Maybe one day I'll be able to make the 1745 work, I hope.

drnoob

· #260 · Jul 23, 2013

Can you guys help me out? I have a flippinout scout and I want to try loops. I have a 32 inch draw and I only shoot 3/8 steel. I want to be around 230 fps to 250 fps (around). Can you experienced guys tell me something I could buy that could achieve this? Longer lasting would be great also

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