Crosman 66 Hunting? Daisy 880 Hunting?

[K.O.]

"-Shim to take space between Valve O-Ring and Valve head."

what did you use, lead wire?

there is a bit of head space that can be taken up in the air passage between the valve nose and check poppet you can put a pin in the poppet

 which has the advantage of acting as a guide pin(but if it comes loose ...) or

safer to sleeve that area and reduce its diameter.

http://www.network54.com/Forum/275684/message/1227571316/head-space+visuals+%28pics%29

[DavidS]

"-Shim to take space between Valve O-Ring and Valve head."

what did you use, lead wire?

No.  I very carefully made it out of Delrin.

there is a bit of head space that can be taken up in the air passage between the valve nose and check poppet you can put a pin in the poppet

 which has the advantage of acting as a guide pin(but if it comes loose ...) or

safer to sleeve that area and reduce its diameter.

http://www.network54.com/Forum/275684/message/1227571316/head-space+visuals+%28pics%29

I did the pin in check valve on my 66, though not my 2289.

[K.O.]

Thanks.

[DavidS]

My focus is for the time beings on the Daisy 880, and what can be done to it.   I do think that I can make a good 14FPE hunting riffle out of it.

Also the on the 66 I did O-Ring the bolt to prevent blowby.   This made a huge difference in performance as well.   I have to admit that I do like the 5 shot clip, I have been thinking about what I could do to make it work with the Daisy (convenient loading).   Just out of curiousity I just sent a pellet into a 3 inch thick of High Density Foam at 1 Pump on my Crosman 66 and it blew all of the way through.  I have never checked velocity at one pump.

[K.O.]

My focus is now going to switch to a Daisy also I want to see what I can get reducing valve volume on my 853 a steel pump handle would be

perfect.

Me I have the big things done on my Crosman's, I mainly have been concentrating on getting my 1325 built, I think it may just turn out to be

a 50 yard hunter.

I still need to do the finer headspace mods on all of mine I have just done the pump cup, do you think .035 aluminum sheet would work  to

make the o-ring shim?



About my 853 it has the L.W.  barrel so it will handle all the fps I can throw at it. I think the daisy fast twist 953 barrel 1 in 15 twist would not,

any way with ~7" stroke and ~.9 pump bore it actually could be made pretty strong even with out replacing the thin aluminum pump tube

with steel and figuring out how to seal it better to the valve. I already bought an extra pump tube in case I go to far and it starts bulging.

[DavidS]

You could probably use aluminum sheet to make the shim, though I would be concerned about the edge coming up while inserting the valve and marring the tube.

LEt me know what kind of power you get out of your 853.   I would love to see a good SSP with enough power to hunt, it would make a good gun for the rare need of a follow up shot (instead of having to keep a MSP pistol charged at all times).   As the 853 is a SSP you will likely have to reduce the valve volume a lot to get good gains.  You will also like want to get rid of all possible head space.

I am thinking that for the Daisy 880 head space is probably the first thing I am going to focus on.   I will also attempt a slight valve volume reduction (along the lines of what I did with the Crosman 66 and 2289).  Then look at the valve exhaust, and barrel transfer ports, see what can be done there to improve power a bit.

[K.O.]

I honestly do not plan on going over about 550-580 if I can get it...

The pump tube walls are only .35 or so aluminum so I can not see it holding up and making a steel tube with just a drill press is more than I want to tackle...

It does look like some minor smoothing or air flow is possible also...

It is at about 425 fps now with 7.9g...

[K.O.]

and yep reducing volume is the plan...

[lillysdad621]

as per the 1322 going over 550... not happening on a 10.5 inch barrel, right? I didn't think that more air would get more velocity, because once the pellet reaches the crown, any extra air still coming behind will blow by the sides... right?

[K.O.]

as per the 1322 going over 550... not happening on a 10.5 inch barrel, right? I didn't think that more air would get more velocity, because once the pellet reaches the crown, any extra air still coming behind will blow by the sides... right?

Imo yep.

[DavidS]

as per the 1322 going over 550... not happening on a 10.5 inch barrel, right? I didn't think that more air would get more velocity, because once the pellet reaches the crown, any extra air still coming behind will blow by the sides... right?

You can get a bit more out of the 10.5 inch stock barrel with some work.    The key becomes getting more of the air at higher pressure behind the pellet so it can do more work in a short period of time.   Now to get truly great speeds you will need a longer barrel, though I see no reason that you could not get up to about 580FPS out of it with the short barrel, maybe even more.

Though remember that with the much higher pressures you will also have a much much louder gun.

[Bryan Heimann]

i am really interested in how the daisy 880 mods go...