Putting a little more power in a $15.00 Daisy
Cvans
Member
- Joined
- Feb 21, 2019
- Messages
- 463
Had a better day today. The big brown Daisy truck showed up with box of parts so everything else was put on hold. Came up with a simple way to plug the hole in the 105's piston. Used a #10 x 32 nylon screw. Drilled the hole out to 11/64" down to where the retainer pin goes in. Then cut the screw to the proper length and using a band saw made a slot in the end of the screw for a screw driver. Seems to work well and the screw also holds the pin in place so there is no chance of it touching the cylinder wall.
Made a shorter preload space as I wanted to add a washer between the spring and spacer. It's my understanding that coil springs like to twist during compression and the smoother they can do this the less they get distorted. Then the abutment was modified by moving the magnet to the side and the air port opened up. As I understand it hinz used a stronger magnet to let compression build before the BB starts down the shot tube. I tried the opposite as an experiment. Using the stock magnet the abutment was machined so that the BB doesn't quite touch the magnet. The idea being the BB can start picking up speed as soon as possible and the BB is held tight against the air passage to seal it. I don't know if it is better but the velocity is now running in the 450's and you can still hear it click when it gets to the abutment. Enlarge the photo and you can see what this is about.
Made a shorter preload space as I wanted to add a washer between the spring and spacer. It's my understanding that coil springs like to twist during compression and the smoother they can do this the less they get distorted. Then the abutment was modified by moving the magnet to the side and the air port opened up. As I understand it hinz used a stronger magnet to let compression build before the BB starts down the shot tube. I tried the opposite as an experiment. Using the stock magnet the abutment was machined so that the BB doesn't quite touch the magnet. The idea being the BB can start picking up speed as soon as possible and the BB is held tight against the air passage to seal it. I don't know if it is better but the velocity is now running in the 450's and you can still hear it click when it gets to the abutment. Enlarge the photo and you can see what this is about.
Last edited:
Wow- I'd say that's better, like by about 100 fps! Is this the double 499 shot tube set up? What spring and how much preload you using? It makes me wonder if there might have been something wrong with the original piston. I'm guessing you cleaned the grease off the spring?
I'm glad you were able to test the weaker magnet, too. And a very good way to plug the air tube hole. Interesting stuff for sure and good job on the machining/fabrication end of things- you guys really got it going on!
I'm glad you were able to test the weaker magnet, too. And a very good way to plug the air tube hole. Interesting stuff for sure and good job on the machining/fabrication end of things- you guys really got it going on!
Cvans
Member
- Joined
- Feb 21, 2019
- Messages
- 463
Yes it's the double barrel. Using the single barrel the velocities were in the 415 fps range.
I used the other spring you sent with the gun. The new preload spacer and the metal washer = the length of your spacer. It was installed with just a thin layer of turbine oil wiped on it. Also the felt spring twang seems a lot less after placing a metal washer between the spacer and the end of the spring.
Some interesting things turned up after reassembling this gun. First it was at maximum velocity right out of the gate. Didn't have to shoot any warm up shots for the gun to come up to speed. I give the the black 1938 seal credit for that. Secondly the gun shot 10 fps faster with the butt stock installed. Guessing it's because the stock dampened the recoil and vibrations in the shot tube.
Next in the plans are some nylon supports for the shot tube to help dampen vibrations and an extended barrel. If the accuracy is good after all that then the stock will need some attention.
Have a good day and thanks for the your support.
I used the other spring you sent with the gun. The new preload spacer and the metal washer = the length of your spacer. It was installed with just a thin layer of turbine oil wiped on it. Also the felt spring twang seems a lot less after placing a metal washer between the spacer and the end of the spring.
Some interesting things turned up after reassembling this gun. First it was at maximum velocity right out of the gate. Didn't have to shoot any warm up shots for the gun to come up to speed. I give the the black 1938 seal credit for that. Secondly the gun shot 10 fps faster with the butt stock installed. Guessing it's because the stock dampened the recoil and vibrations in the shot tube.
Next in the plans are some nylon supports for the shot tube to help dampen vibrations and an extended barrel. If the accuracy is good after all that then the stock will need some attention.
Have a good day and thanks for the your support.
Cvans
Member
- Joined
- Feb 21, 2019
- Messages
- 463
Spent this afternoon working on the 499 again. Made a rubber snubber to fit half way down the barrel and the air tube. But didn't see any improvement in the velocity.
Then decided to go ahead and extend the barrel to support the extra air tube. Took an old abutment and made it into the cap for the barrel. Threaded the end of the air tube for it to screw onto. Turned down the end of the plastic funnel for the other end of the barrel extension to slide onto.
Assembled it and ran into a problem. Now the abutment is turning in the gun and I can't get the original barrel out. But the gun was assembled so I ran it over the chrony. What happened was beyond anything I was expecting. Below was the first shot.
The next photo was the third shot and the rest were in between these two. So Vibration in the extension does have a bearing on velocity.
Was hoping to post some photos of nice groupings but ran into another issue. The plastic funnel is only held centered in the barrel by four little (very little) plastic ribs.
Once these get abused a little bit they flatten out and the barrel start floating around. My first groups were pretty good but then started spreading out. I thought maybe the extension was coming loose but it wasn't. Did notice a lot of play and it was coming from between the barrel and the funnel. So that is going to have to be dealt with before and more groups are shot. That's where things stand as of today.
Then decided to go ahead and extend the barrel to support the extra air tube. Took an old abutment and made it into the cap for the barrel. Threaded the end of the air tube for it to screw onto. Turned down the end of the plastic funnel for the other end of the barrel extension to slide onto.
Assembled it and ran into a problem. Now the abutment is turning in the gun and I can't get the original barrel out. But the gun was assembled so I ran it over the chrony. What happened was beyond anything I was expecting. Below was the first shot.
The next photo was the third shot and the rest were in between these two. So Vibration in the extension does have a bearing on velocity.
Was hoping to post some photos of nice groupings but ran into another issue. The plastic funnel is only held centered in the barrel by four little (very little) plastic ribs.
Once these get abused a little bit they flatten out and the barrel start floating around. My first groups were pretty good but then started spreading out. I thought maybe the extension was coming loose but it wasn't. Did notice a lot of play and it was coming from between the barrel and the funnel. So that is going to have to be dealt with before and more groups are shot. That's where things stand as of today.
Very cool!! That could pass for factory, and the MV looks very good too. Interesting how the harmonics plays a part. I don't pretend to understand the ins and out's of it all, but it does seem to be "a thing".
I know what you mean with the 4 little ribs that serve to center the funnel- not going to last very long. Besides the funnel allowing the shot tube to wander, one other thing I wanted to mention about the loss of accuracy is the shot tube may be getting oil fouled from oil coming from the compression chamber. Any oil is too much oil in the shot tube. On guns I just resealed it can foul in 5 shots and need cleaned. Eventually it'll only need cleaned every once in a while. But the first thing I always do is clean the shot tube when I start seeing any loss of accuracy.
I keep going back and looking at your extended 499 and it really looks good like that.
I know what you mean with the 4 little ribs that serve to center the funnel- not going to last very long. Besides the funnel allowing the shot tube to wander, one other thing I wanted to mention about the loss of accuracy is the shot tube may be getting oil fouled from oil coming from the compression chamber. Any oil is too much oil in the shot tube. On guns I just resealed it can foul in 5 shots and need cleaned. Eventually it'll only need cleaned every once in a while. But the first thing I always do is clean the shot tube when I start seeing any loss of accuracy.
I keep going back and looking at your extended 499 and it really looks good like that.
Cvans
Member
- Joined
- Feb 21, 2019
- Messages
- 463
Thank you.
I've got to get rid of that ugly sight. The extended stock would look nice under that barrel. I'm toying with the idea of making an aluminum part to replace that plastic funnel. Just thinking the whole thing would become a lot more solid if it wasn't plastic.
I still get a kick out of listening to that BB go down the air tube. Kind of like dropping a rock into a well.
I've got to get rid of that ugly sight. The extended stock would look nice under that barrel. I'm toying with the idea of making an aluminum part to replace that plastic funnel. Just thinking the whole thing would become a lot more solid if it wasn't plastic.
I still get a kick out of listening to that BB go down the air tube. Kind of like dropping a rock into a well.
Very good idea on plugging the rubber plunger! I’ll be giving that a try. On the magnet placement, you are very similar to one of the tries I did. I’ve used the stock magnet in 2 locations. First was as close to the shot tube seat as possible. The second was centered on the lag diameter that you drill through, so it was further away from the bb. The one with the magnet closer to the seat had a bit higher mv. Then I got the 3/16” dia x 3/16” long magnets and drilled through just centered on the flat area. I pushed one in flush to the bore of the abutment. Better mv. Then put another on top so a combined 3/16”x 3/8” n52. About 4# pull. That was the best result for me. The hole is reamed at 0.1685”. Pushed in a countersink yo make a bit more funnel shape to “minimize” turbulence as the air is displaced. Soooo, don’t know how to know if this all allows some small amount of compression to build up before the bb breaks the magnetic field, but I think it does. Glad you are pursuing this project!
Looks good! For me, this all takes multiple tries! What material did you make your extension from?
Thanks to a heads up from Cobalt, I have a very abused 499b coming soon. I think in some ways, that it will make a better platform for our high mv testing. Maybe a better home for the LW tube. I’m feeling better and hope to do some more work on this project.
Kudos to all participating! All ideas are welcome and carefully considered.
Kudos to all participating! All ideas are welcome and carefully considered.
Cvans
Member
- Joined
- Feb 21, 2019
- Messages
- 463
Now your going to make me admit I messed up. I had intended to use a piece from another barrel. Cut the piece in the chop saw and all was good. Placed it in the lathe to square things up and the tube having a split seam didn't agree to this. Planned on making a very light cut but it still caught on the seam and ruined the barrel.
Having flown and worked on Ultralight aircraft I had some aluminum tube that was the same OD. It's 6061 and is nice to work with so that's what the extension is made of. If you need some let me know.
Glad your feeling better. Have missed your posting here.
Cvans
Member
- Joined
- Feb 21, 2019
- Messages
- 463
When the gun is apart again I'm going to try another magnet 180 degs from the first one just to see what two magnets will do. Trying to keep the BB centered in the abutment port.
Just a heads up. My abutment has started turning in the cylinder so the barrel can't be unscrewed. Going to have to stake it somehow so that it can still be easily removed. Maybe a set screw.
Just a heads up. My abutment has started turning in the cylinder so the barrel can't be unscrewed. Going to have to stake it somehow so that it can still be easily removed. Maybe a set screw.
Thanks. I’m guessing you had the tube in a 3 jaw? I will be trying the same process using collets. I’ve thought about making a split block with 2 holes that would clamp a barrel shroud with the small tube underneath to be able to mill the ends square. Or to hold it square to a disk sander. It should also work with the barrel tube only. I’ve considered several ideas for barrel shroud extension but haven’t settled on anything yet.
I’ve also considered the 2 magnet option but haven’t tried it. I have some thought that perhaps having the magnet oriented to the bottom is part of daisy engineering to put a bit of spin on the bb “hopup”, or “hopdown”. I will at some point do an abutment with the magnet at the top, which is how, if I understand correctly, that hopup is normally done. This is all conjecture on my part.
When my 499b and parts arrive, I hope to do another build. If I can get back to a reliable 500+ mv, then will try to figure out how to actually shoot a target. Or just sent it to Cobalt for proving!
Not surprised that you are having issues with the abutment rotating. I had planned on the single shot 105/1938 style to drill holes through the shroud 180 deg apart @ 90/270 deg and tap for a small screw on each side. Fighting the staked bumps is annoying....
Just a though to hold the abutment enough to unscrew the tube. Maybe make a long tool to drive in the abutment from the air chamber side to hold it from turning. Perhaps a torx bit or a screwdriver. Would leave a bit of a mark, but that could be dealt with after a successful abutmentectomy!
I've been fortunate that the abutments in my guns have stayed put. I don't tighten the shot tube very tight so it's relatively easy to remove and the threads are lubed to help with that.
Guys, what is the blind hole in the abutment for, anyway? (Photo shows the seal on backwards- I had 2 come from Daisy like that. Almost installed it that way, too.)
Guys, what is the blind hole in the abutment for, anyway? (Photo shows the seal on backwards- I had 2 come from Daisy like that. Almost installed it that way, too.)
Well, mine, in the pix is backward also. I have to pay more attention to that! Thx!
I have speculated that daisy may have an assembly tool to insert into the air hole and that hole to rotate the abutment for alignment. Kind of a pin spanner tool. Let me know if I win a prize!
That makes sense, thanks for the insight- never occurred to me, and I'm a tool junkie! The seal might not make all that much difference but it would be better to have the open side facing the piston so it would expand against the shroud and not let any air get by.
Cvans
Member
- Joined
- Feb 21, 2019
- Messages
- 463
These last entries are priceless.
I'll figure something out. Might take some careful measurement and drill through from the outside and install a set screw. Gotta be careful as I don't want to put any scratches in Mark's gun. I've wonder about that little hole in the abutment also.
A parachute type seal definitely works better with the lip facing the pressure.
That's impressive considering the subject matter.
Maybe, before you drill a hole, make sure of abutment magnet orientation. I have some gut level feeling that it makes a difference. Maybe drill the staking locations. It would be hidden and the is a ready made center punch hole. Then the set screw could seat in the abutment staking slot(recess).These last entries are priceless.
I've wonder about that little hole in the abutment also.
A parachute type seal definitely works better with the lip facing the pressure.
That's impressive considering the subject matter.
I’ve been wanting to get one of the cheap endoscopes to look at the inside of these projects. Not needing to perform an abutmentectomy, but need to do a surgical removal of the abutment sleeve on the older style shrouds. 94,99, 1938.
Anyone have endoscope advise?
You all are certainly correct about seal orientation. I am embarrassed!
I got a 'scope from a Chinese importer named "Banggood". Not kidding. Their grasp of English is priceless. Anyway, it's 5.5 mm at the lens/led end, 1 m long, illuminated with 6 LEDs and pretty much self contained. Cost me all of $11.00 delivered. Likely there are other importers offering much the same thing.
I'd be happy to send it to you but by the time we mailed it to and from, we'd have spent enough to buy one!
https://www.banggood.com/search/endoscope.html
I'd be happy to send it to you but by the time we mailed it to and from, we'd have spent enough to buy one!
https://www.banggood.com/search/endoscope.html
I had only looked at amazon. Are you satisfied with image quality? Do you use it with a phone? iPhone or android? Thx!
It will work on a phone but I've only used it plugged to my laptop. Resolution is what I would call adequate (described as Resolution: 640 x 480 or 1280 x 720 only on Computer) but far from what my ancient Pentax 5 mp digital camera can do. I got mine to see inside assembled engines at the track to check for damage so uber fine detail wasn't a priority. I don't have any captured images from it, they are all on a different laptop that the hard drive gave up the ghost.
I'll get it hooked up and do a couple screen captures of the inside of a BB gun. I need to get it up and running on this laptop, anyway.
I'll get it hooked up and do a couple screen captures of the inside of a BB gun. I need to get it up and running on this laptop, anyway.
Last edited:
