Putting a little more power in a $15.00 Daisy

The photo below shows the powerplant of the "the most accurate BB gun in the world"- the single shot Daisy Model 499B Champion. The part on the left is the ‘Abutment Plug Assembly’ (both sides shown), next is the ‘Shot Tube’. Below them is the ‘Plunger Assembly’. And under the plunger assembly is the test target that was included w/the shot tube- just like the “big boys”!

It’s apparent the shot tube assembly consists of a much shorter shot tube than the length of the 499B gun itself would indicate. The black plastic piece on the right end is a funnel to make muzzle-loading the single BB easy to do. Also interesting to note, the 499B does not use an air tube. The combination of no air tube along w/the lower spring rate accounts for the low velocity of the 499B (~240 fps), but at 5 meters high velocity isn’t necessary for great accuracy, apparently. Also noteworthy is the shot tube threads into the abutment assembly using fine threads (5/16-24)- no air loss and makes for a rigid assembly, all in all. As a point of reference, the Model 25 and the removable shot tube lever guns like the early Red Ryder use a coarse 7/16-14 thread. And interesting that the Model 25 shot tube screws right in to the old style Model 104 I have. Leaves the end of the shot tube unsupported because it's longer than the barrel shroud of the M104, but it shoots fine.

The 499B shot tube has a larger OD than the Red Ryder, so adapting the 499B shot tube to the Red Ryder’s shot tube assembly will not be a 'plug-and-play' deal. There’s a slim chance I can use the 499B abutment in place of the Red Ryder abutment- if that’s doable the rest will be easy. I’ll know more once I’m finished w/the accuracy testing and can pull the shot tube from one of my Red Ryders.

After finding the Model 25 shot tube works (quite well, actually) in my old Model 104, I got to thinking about adding 2” of length to the barrel shroud of the 104 to be able to use the Model 25 shot tube w/o it being unsupported- which just killed any hope of accuracy. So I rummaged around in my plumbing junk and came up w/a length of thin walled 3/4” copper tubing that has the same dimensions as the 104 barrel shroud. A trip to Ace got me a coupler to join the copper tubing to the shroud. All that’s left is to sweat the joint between the tubing and coupler then cut it to length. The coupler is a nice tight fit on the barrel shroud and it also butts up against the front sight post, so that- along w/threading the shot tube into the abutment- will ‘sandwich’ everything in position for shooting.

The hope is there will be an improvement in velocity and accuracy over the shot tube from the 104- a shot tube that has had many, many thousands of BBs through it during its 40-plus years of service. Actually the longer barrel length will do nothing for velocity (will hurt if anything), but if the bore is tighter than the old shot tube that may give it an edge. As far as accuracy, any improvement will have to come from the Model 25 shot tube being less worn than the 104 part. Now, if the sight radius was extended the same 2” as the barrel length, that could potentially help but at this point I don’t intend to relocate the front sight- unless I see enough gains overall to warrant it.

I have established a baseline for velocity of the 104 using the original shot tube and broken piston (now pinned on) and worn barrel seal at 238 fps using the standard Daisy Precision Max zinc BB from WM . I will shoot it for accuracy this evening after the wind dies down. The replacement piston, seal and air tube for the 104 (thanks again to Ken @ Daisy Gun Works) should be here any day now, once they’re here I will rebuild the powerplant, break it in, then test it again for velocity and accuracy using the original shot tube. Then I’ll compare those results to what I get using the Model 25 shot tube. I have no idea what to expect but I'm interested to see what I'll find!

The wind died away so went out and got a baseline for accuracy w/the Model 104, before any repairs. Shooting right around 240 fps, using my “standard” BB- the Daisy Precision Max zinc plated from WM- the 10 meter 5 shot group measures 1.82”:

That's a bonus! Must be something PA does- mine came w/just the Owner's Manual.

Got the Model 104 back together using the Model 25 shot tube. First photo is the tubing and coupler sweated together and prepped for cutting and painting:



Next are the unassembled components:



And finally, the reassembled gun:



It’s dark outside so all I was able to do was verify it shoots. Accuracy and velocity will have to wait until tomorrow. Seeing as how the powerplant is injured (piston broke and has been pinned to the shot tube) and muzzle velocity is just ~240 fps, I'm not expecting anything great for velocity, but I might see some improvement in accuracy. Or not- one thing I have found is to expect the unexpected!

I spoke to Ken @ Daisy Gun Works yesterday, my parts went out already so should be here directly. Once the powerplant is rebuilt I can see what it can really do.

It was still outside this morning so I went ahead and shot the Model 104 w/the Model 25 shot tube for accuracy. First I shot it w/the added tube longer than actually needed. I did this to allow the tube to be shortened to allow the shot tube to be 'clocked' to where it shot the best, and to assure the muzzle end of the shot tube would be tight against the tubing before the threaded end of the shot tube bottomed out against the abutment inside the barrel shroud. If it did I was sure accuracy would be hurt by the muzzle end being less supported than if the end of the shot tube was tight against the added tubing. I shot 2 groups of 5 shots each, they are marked in a different color highlighter to tell them apart. The results are below:




I noticed straight away that the gun was shooting harder than it had when using the original Model 104 shot tube. How much harder? I just had to find out so I went ahead and shot it for velocity and got the following (surprising!) results:

DAISY MODEL 104, ca. 1970s w/Model 25 shot tube, 5 shots:
• 281 fps Extreme spread 3 fps

Average was 238 fps using the original shot tube, all else the same. It would seem the Model 25 shot tube assembly is a decent piece. The velocities are the same between the new Model 25 and the Model 104 using the same Model 25 shot tube.

I have to say again- I was surprised. Did not expect to see that much increase (~18%) and in fact wouldn't have been surprised if it did no better at all. But very good for just an updated shot tube assembly when all things are considered, like the gun's age and condition- especially the pinned-on plunger piston! (I'll be sure to get a photo of the pinned-on piston when I pull the gun back apart to rebuild the powerplant.)

For reference, the following are the velocities I got w/the other guns using the same BB:

STOCK DAISY MODEL 105 BUCK
• 260 fps

STOCK DAISY MODEL 25
• 282 fps

STOCK DAISY RED RYDER
• 270 fps

STOCK SHERIDAN COWBOY
• 329 fps

MODIFIED RED RYDER #1
Drilled air tube to 3/32” ID
Preloaded spring 7/8”
• 328 fps

MODIFIED RED RYDER #2
Drilled air tube to 3/32” ID
Preloaded spring 1/2”
• 335 fps

Now back to accuracy. Next I made the tube enough shorter to allow the shot tube to be turned in by about 3/4 of a turn. I found that to be where the barrel shroud/shot tube seemed to shoot the best. The breech end threads still don't bottom out before the muzzle end is tight, so I'm good to go there. I reloaded the shot tube w/the same "standard" Daisy Precision Max BBs and got the following results:



1.23"! Not quite as good as the 1.1" group the little Model 105 Buck shot, but better than all the others. And again, darned surprising, all things considered!

FWIW, I'm not reading anything into the two uber short stocked guns being more accurate than the others- for now I consider it to be just "one of those things". But even if the short stocks are more accurate across the board from a rest, I just cannot shoot the short stock guns worth a hoot offhand: when trying to get a cheek weld the thumb of my strong hand hits my nose, my eye is too close to the rear sight, and it generally forces a very unnatural way of holding the gun on target. I cannot imagine having to shoot that way all the time so accurate or not, it’s a moot point for offhand shooting.

Next will be a retest for accuracy and velocity using the same gun and shot tube, but w/the powerplant freshened up. Any guesses as to what the results will be?

I tend to agree- if I see 300 fps, that would be a success to me. Even 280 fps I can live with. I wish my modified Red Ryders would group like that! Just a puzzler why the short stock guns are doing so well but just not enough testing yet to draw any real conclusions. But if the shorty's continue to outshoot the long guns, maybe I need to try a short stock on the Red Ryders to see if they shoot any better!

The parts for my Model 104 just got here. Looks like what you’d expect except for the barrel seal. This seal fits down inside the muzzle side of the barrel shroud and sits against the abutment. Besides sealing the compression chamber, the barrel seal is what stops the piston at the end of its travel when the gun is fired, so it takes a real beating. It has a hole in the center for the air tube to pass through. The new barrel seal is like this, except there’s what looks like a nylon ‘insert’ that has an ID that perfectly matches the air tube OD. This should mean less friction and a better air seal. I’m also willing to bet this seal will do a better job over the long run because- if my old seal is any indication- the center hole wears larger over time, where the new seal’s insert won’t wear anywhere near as much.




Next up is to break down the 104 and install these parts. Testing to follow…

flightsimmer said:

My newer model 25, bought a couple or three years ago, has a tiny magnet mounted on the rear of the shot tube to hold the BB in place for firing, so I doubt that the copper plated lead BB'S would work right in it.
But, for accuracy testing I could make it due if I can find some.

Click to expand...

No one around here carries them. But you're right! Non magnetic BBs will be a problem for all the new models that use the magnets and I hadn't considered that. I went back over the article I linked to and Tom Gaylord mentions needing to keep the barrel above the horizon to keep the lead BBs from rolling out of the barrel!

I rebuilt the 104, power is decidedly down from what it was. It's still dark so no chrono info but I'd be surprised if it was over 240 fps. Really bad. I've gone back in to double check everything and I did notice the original piston is designed differently than the replacement and it causes a little more drag, but there's no difference between the replacement piston and the pistons used in the Red Ryder and Buck, and the action feels nice and smooth when I cock the gun so that really shouldn't be a problem. The replacement air tube has the air port located a little differently than the original so I tried going back to the original air tube, but no help there. Also, I lubed it as I usually do. So I'm not sure what's going on but I will get to the bottom of it- one way or the other!

Gratuitous photos:
Below are two air tubes, left is drilled to 7/64", on the right is a stock part.


Below is the Model 104's broken piston, pinned to the air tube. The end of the pin is discolored blue from heat, caused when I ground the end to the right size to fit up inside the plunger tube. (If the pin didn't fit inside the plunger tube the whole plunger assembly couldn't be made to work.)

Went out this morning after the sun was up far enough and checked the velocity of the sickly “rebuilt” 104. Not even as good as I thought- of 6 shots, the high was 211 fps, low was 201 fps. Dismal to put it mildly.

So I’m sitting here thinking of what could be the problem. I happened to look over to my side and down on the floor, what do I see? It’s that darned nylon insert from the barrel seal! Laying right there, plain as day!! I was happy to have found it but kicking myself at the same time for missing it when I went back into the gun looking for problems. The insert just was not on my radar- but you can bet it will be going forward!

Going to replace it and retest for velocity. Fingers crossed...

Finally- success. Retested w/the barrel seal and seal insert installed correctly and got the following results:

• Average velocity 286 fps (old pinned on piston was 281 fps)
• Extreme spread 5 (old piston was 3 fps)
• Highest was 289 fps

I would expect the velocity to maybe pick up a bit from this but for the most part, what you see is what you get. However, I do believe the ES will tighten up once it's broken in. I will retest it after a few thousand rounds to see...
Obviously my jury-rigged piston was doing its job, seeing as how the velocities between it and the new piston and seal are virtually identical. But the pinned-on piston was doomed to fail if used frequently- the thin pin would have pulled through the old piston material (or it may have lasted forever- I just wasn't willing to find out!).

It's real windy today so no accuracy testing until it dies down.

A tip for anyone who may find themselves in the position of having to put the insert back into the barrel seal, just remove the seal and reinstall the insert. Forget trying to finesse it back into the seal w/the seal still in the barrel- once the seal is in the barrel the hole for the insert closes up too much and you'll never get it back in. The much better option is don't be careless like I was- remember there is an insert and make sure it's where it's supposed to be!

Above, I mentioned there was a difference between the new and old pistons. The photo illustrates what I was getting at. Like it says- no idea if the old seal was made w/the walls as parallel as they are or if that's just how the seal wore or took a set after having been installed in the chamber for 40-plus years. But I tend to believe it's caused by the piston taking a set.

Shot these at 15 meters. No idea of how many BB hits it takes to cut them in half but I can tell you it’s a LOT!!



(Top pair I posted already.)

Well, they were hanging by their pull tabs from a branch (top pair still has the twine attached), turns out the shots going in cause a horizontal tear in the can, shots going out just make a small hole. No idea of why they behave like that...

Earlier I had said the piston travel of the Daisy guns was 2". I happened to notice the Cowboy was a bit different than I remembered, so I re-measured them all. Results below:

PISTON TRAVEL

• 1-7/8” for 2016 production Red Ryder, Buck
• 1-29/32” for 2016 production Sheridan Cowboy
• 2-1/8” for ca. 1970 Model 104 and 2016 production Model 25

The 2016 Red Ryder, Buck, Sheridan Cowboy and old style Model 104 all use a 7/8" OD piston. The 2016 Model 25 uses a smaller, 13/16" OD piston. The swept volumes are below:

SWEPT VOLUME

• 1.10 CID for 2016 production Model 25
• 1.13 CID for 2016 production Red Ryder, Buck
• 1.15 CID for 2016 production Sheridan Cowboy
• 1.28 CID 2-1/8” for ca. 1970 Model 104

From post #85:

cobalt327 said:

This [barrel] seal fits down inside the muzzle side of the barrel shroud and sits against the abutment.

Click to expand...

The above should read "This seal fits down inside the breech side of the barrel shroud...

Sorry about that.

I decided to remove the anti beartrap 'rack' from the Cowboy trigger assembly (both modified Red Ryders have had this done already). The reason for this is to make cocking the gun smoother and quieter, as well as improving the trigger pull. Turned out to be easy to do: The bushing slides out the left side, I used a drill bit to remove it as well as to be a pilot to keep everything in alignment, as I didn't want to fully disassemble the trigger at this stage. Be aware this voids the warranty and I'd not advise doing this if there was any chance a youngster or an inexperienced shooter was going to handle the gun.

COWBOY REASSEMBLY TIP

The Cowboy uses a different type of hardware than the Daisy. Instead of a normal screw and nut like we’re all familiar with, it uses a type of binding post. Both types of hardware are shown below.


The Cowboy uses three different length ‘nuts’, two are only slightly different. And there are two different style screws. If care is used to keep them in order, there’s no problem. That’s if you know beforehand there’s a difference - which I didn’t. So I mixed them up and it wasn’t until later that I realized my mistake. So in case anyone else gets them mixed up:

• LEVER: 1 short, 6mm OD x10.2mm long barrel nut used for lever pivot. Also uses the traditional M4-0.7 x 5mm long button head screw (called "semicircular allen screw" on parts list).
• STOCK: 2 barrel nuts (24.2mm long x 5mm OD) are for attaching the stock. Uses what the parts list calls “countersunk allen screws”- M4-0.7 x 5mm long button head screws. The underside of these screws are like the underside of a flathead machine screw (example shown below).
• TRIGGER AND SPRING ANCHOR: 2 slightly longer barrel nuts (25.2mm long x 5mm OD) are for the trigger and spring anchor pin. Uses the traditional M4-0.7 x 5mm long button head screws (called "semicircular allen screw" on parts list).

Note- There’s really no advantage in removing the anchor nut/screw, the spring anchor can be removed w/the anchor nut/screw in place- same as how the Daisy is done.



At first I liked this style hardware. Having smooth button heads on both sides looks good, it doesn’t snag on anything, the hardware can't be overtightened to the extent that it warps the sides of the receiver (like can happen on the Daisys, especially the new ones) and for the most part they weren’t any harder to work with than ‘normal’ Daisy hardware. But I ran into a problem, so I’m mentioning it here so others might avoid the hassle.

My troubles began when I went to reattach the cocking lever. Because the sides of the receiver are pulled together by the hardware, there’s some force required to tighten the screw and nut. The amount of thread engagement was insufficient to keep the threads from stripping, and strip they did. The screw is still okay but the ID of the nut is stripped. I had a few options:

1. Order new hardware from Crosman
2. Replace the original screw and nut with traditional style M6 hardware (or equivalent SAE)
3. Come up w/something that would wear better than #2

#1 would take too long and there’s no sport in it.
#2 would work- at least for a while. Problem w/it is the pot metal lever would be bearing directly on the threads of the screw. Given the strong spring, the short lever throw compounds the force applied to the pivot- a recipe for wearing the lever out quickly.

Left w/option #3, I found a small brass bushing that fit the lever and receiver holes. It was secured using a machine screw and nut after liberally lubing it with Super Lube grease. I should mention at this point that the lever uses 2, thin thrust washers that go between each side of the lever and the inside of the receiver. These are a bear to keep in place while putting the hardware back in. Use a daub of grease to hold them in place and a lot of patience!

After repairs the gun is working normally- no difference in the cocking effort and feels the same. I don’t expect the brass bushing to wear out any time soon but I’ll keep an eye on it just the same.

In the upper photo I've stacked the Daisy Buck atop the Cowboy, both of which are atop a Red Ryder w/the factory RR stock.

Earlier I took a photo (bottom) to show the difference between the LOP of the little Model 104 with it's plastic stock, the Red Ryder and the 'adult sized' chief aj stock. (The Model 104 plastic stock is the same length as the new Model 105 Buck.)

As can be seen, the Cowboy's stock is barely longer than the Model 104 and Buck, and is considerably shorter than the Red Ryder w/the factory stock, let alone the adult stock. The Cowboy having such a short stock strikes me as quite odd. I really don't get why this gun would have a buttstock scaled for a child, yet have a longer barrel (and sight radius) and by far the hardest cocking effort, as well as having the highest as-delivered velocity of all the unmodified BB guns I've tested here.

I mentioned earlier how the short stocked guns were harder for me to shoot offhand. I decided to put a concerted effort into trying to overcome this on my Model 104 that I modified to take the Model 25 shot tube (which has continued to work excellently, BTW).

I found that changing the way I held the gun with my right hand has helped quite a bit. Instead of wrapping my thumb over the comb like I do on a normal LOP stock, I'm now tucking it down on the right side of the gun, and I'm putting my non trigger fingers through the lever instead of holding the gun by the bottom of the lever. This allows me to get a semblance of a cheek weld to the stock w/o my nose and thumb to occupying the same space, and has helped offhand accuracy a lot. In fact, I believe that if the sights were the same as the Red Ryder (instead of the crude stamped rear sight that doubles as the spring anchor), it would be just as accurate offhand. Not as comfortable to shoot, though.

LoonWulf said:

Great work again Cobalt, Im learning more about these things than i ever thought i would.

Click to expand...

You and I both! Would never have imagined something so simple would hold my interest like these have. And thanks again for the support.

Next I want to see if I can get an honest 350 fps from a new style Red Ryder. I plan to use an air tube bored out to 7/64", and the spring from the Cowboy (possibly the plunger tube as well, if it'll work in the Red Ryder w/its roller). I'll add some preload to it- I'm pretty sure it'll handle at least 1/2"- but exactly how much will depend on what the "weal link" plunger tube can take w/o deforming too much.

Kinda funny when I read Daisy stating the velocity is "up to 350 fps" for a stock Red Ryder!