Daisy 880 Better Piston Idea:

[DavidS]

My Daisy 880 has become my primary gun.   I shoot it every day, at least 30 shots.  And at this time I have only one Daisy 880 .

I have gotten to like this gun so much that I am considering getting more Daisy guns as time permits.

The trouble is that I have not had the chance to tear it all the way back down to get all the photos to write up the modifications that I have done to it.

So I have an idea for another very simple modification (and this will also give me an excuse to tear it back down all of the way and finish the photos).

First the reasoning:
The piston head on the Daisy 880 has the O-Ring placed rather far back, and it has a notch cut into the end of the piston to add head space, thus limiting the max pressure, and reducing pumping efficiency.

I have already filled the notch in the piston head on mine.   This leaves the extra head space between the O-Ring and the piston head.

So my plan is:
Take the stock piston head out and measure it.   Then use these measurements to make a new piston head that has the O-Ring slot nearer to the front of the face of the piston.   This will give a perfectly flat face, with less head space ahead of the O-Ring.

I will also cut the O-Ring grove so as to ease adding a Nitrile shim in front of the O-Ring that extends to the face of the piston thus effectively eliminating that head space all together.    I intend to cut the piston tomorrow morning as soon as I finish the Crosman Piston that is in the lathe right now.

[DavidS]

Let us hope that the Daisy 880 can become as much a modders gun as the Crosman 13xx/2289 are now .

Also the Daisy 880 is way easier to modify than the Crosman guns.  There is no need to even have a punch .   All the tools that you need for 95% of all modifications are a set of screw drivers.   To make parts  you need some form of lathe (A good drill with some kind of guide bushing can be used, and some do use it [often referred to as a poor mans lathe], though I have a metal working lathe so that is mute for me), a drill (preferably a Drill Press), some drimel tools, and that is about it.

I enjoy modifying my AirGuns, as it teaches me about each gun in full.  I think it is a good idea to be able to repair anything that may go wrong with any AirGun that a you own.  And it is fun to modify them, so learn to work on the gun while having a little fun, what could be better?

The Daisy 880 is already one of the most accurate, and most powerful MSP AirGuns around.  And it is also marketed as the Daisy 901, and as the Winchester 77x.

I will be doing all future power testing using the telephone book.  I will be counting ripped pages for each shot and taking the average of 5 shots, and posting the number of pages torn.   I will also stick to the Crosman Field Hunting Pointed pellets for power testing from now on, so as to give a good consistent comparison of improvement.

[stonykill]

 interesting. I'll b following

[longhunter]

same here. i've got one sitting in the closet, collecting dust. it was my grandson's. it shoots way to the left. he lost interest. now, it's mine to tinker with.

[DavidS]

Well here I am a day late.   I broke an end mill bit in the lathe ruining two Crosman pumper pistons.  That wasted most of the day.  Not sure why I bother with any of the Crosman guns other than my 2289's, any more.

So we should see a new Daisy 880 piston tomorrow (I hope).

[Big Bore Bart]

  Using end mills in the lathe, it's better and easier on the tool, to plunge cut with center-cutting tools, than try to side load them.     Nibble out the slot a half tool width at a cut to full depth, then take a finish/clean-up pass in each direction.

[DavidS]

I will be delayed further.  I just measured the Daisy 880 Piston, and I do not have any round stock that is bigger than 0.721 inches (the OD of the Piston).   So I will have to grab some next time I am shopping (need to stop by the yard store).