Author Topic: Nearly pointless mod on a cheap Dasiy 901 (Read 7140 times))

blind dog · « **on:** December 19, 2011, 10:09:29 PM »

Just to stay out of trouble, I don't recommend anyone getting inside their airguns, because I never know what anyone else can or can't do. But here's a little power mod I did to my Daisy 901. I got about 10% more muzzle energy with it. But probably not a lot can be done with this design. But I like to tinker!

This is where the the hammer opens the valve…and not very much.

The hammer is the more or less flat bar that pries open the valve stem quickly as it swings up and hits it after the trigger is pulled.

As the hammer flies upward (in the picture) it catches the C-clip on the valve stem, knocking it open and holding it open until the gun is cocked again. The little chamber area under the valve stem is where the pressurized air is contained after pumping up the gun. This valve allows the air to blast upwards through a port into the chamber, driving out the pellet.

In order to open the valve sooner and further to help airflow, I cleaned and roughed up the hammer notch that hits the valve and used J-B Weld to fasten a small steel washer over it.

Shaped and filed:

I also stretched the hammer spring just a little to make it stronger. (Safety glasses on whenever working with, removing, or installing springs.)

This is where it fits over the spring boss on the hammer.

This is the trigger safety catch that will not allow the trigger to be pulled until the bolt is closed.

It goes in like this if it falls out. The end has to drop into that little shelf there.

The hammer holds it in.

The trigger has a little nub that has to go up through the rectangular hole in the safety tab.

This was a little tricky. I take the cross pin out of the hammer and slide it to the rear of the action to get some space between the hammer and trigger spring bosses in order to get the spring to fit between them. Then I shove the hammer forward again and try to get the hammer pin hole to line up with the holes in the sides of the housing. The safety tab likes to pop up and out of that little ledge if it isn’t held down. A nail, a little smaller than the hole on one side, and a pin punch on the other helped.

The top view of the safety tab as it sets. If it is sticking all the way up so the nose isn’t caught under the ledge there, the bolt will not close. Note this safety has nothing to do with the trigger block safety that you operate by hand.

aznboi3644 · « **Reply #1 on:** December 20, 2011, 12:56:09 AM »

is this the same trigger assembly as in the Daisy 880?

poomwah · « **Reply #2 on:** December 20, 2011, 08:41:24 AM »

Quote from: aznboi3644 on December 20, 2011, 12:56:09 AM

is this the same trigger assembly as in the Daisy 880?

it sure looks like it

blind dog · « **Reply #3 on:** December 20, 2011, 08:31:56 PM »

Yeah the 880, 901, 22SG are pretty much all the same Powerline guts. The .22 has a bigger boring through the chamber but a .177 can probably be even changed to .22 by drilling it out and putting in the .22 barrel. I'm working on one of those right now, actually.

-Rob

Toolmaker · « **Reply #4 on:** December 20, 2011, 09:15:06 PM »

Thanks for sharing. There just aren't many mods out there for the Daisy guns so it's great to see when someone does tinker with one.

dwood5 · « **Reply #5 on:** December 20, 2011, 09:24:53 PM »

I don't own a Daisy!

But I think congratulations are in order and thanks for the very professional presentation and photography. One of the best I've seen on ANY forum!

DON

blind dog · « **Reply #6 on:** December 21, 2011, 08:59:33 AM »

Wow, thanks, Don and toolmaker.

Yeah not much out there on Daisy Powerlines, I suppose, because no one sells kits for them(?)
But they are cheap enough I figure you can buy 2 Daisy if you have to, and use one for a parts gun.
They are a very straightforward design though, and I have no trouble getting them apart and back together multiple times with a little care and a dab of silicon grease on the seals and o-rings, and they just keep shooting!

hoagy · « **Reply #7 on:** December 21, 2011, 12:58:58 PM »

good info...never seen the inside of one

momosgarage · « **Reply #8 on:** December 21, 2011, 01:23:33 PM »

Wow, there is a lot more metal parts inside a Daisy than I thought. I tried to ask on the general forum, but got shot down pretty quick. Do you think if some of the plastic inards were made of metal, more power could be squeezed out of the Daisy rilfes? I was thinking of getting a 3D scan done on the plastic parts and then having an aluminum copy carved out in a CNC machine. There are a dozen places near my house that have this service for movie props. Here is my other post for reference:

http://www.gatewaytoairguns.org/GTA/index.php/topic,22943.0.html

blind dog · « **Reply #9 on:** December 21, 2011, 01:31:56 PM »

That's a cool service, but all these parts here are already metal. Even the trigger assembly is black painted cast metal...I assume zinc alloy. The only non-metal is the valve plunger so it can seal against the metal valve face--and of course the o-rings. The receiver and bolt are plastic but all the working innards are all metal. Way to go, Daisy.

momosgarage · « **Reply #10 on:** December 21, 2011, 01:44:03 PM »

I actually tried to ask on the GTA forum about Daisy mods a while back and all the discussions were circular:

http://www.gatewaytoairguns.org/GTA/index.php/topic,22554.0.html

http://www.gatewaytoairguns.org/GTA/index.php/topic,20676.0.html

http://www.gatewaytoairguns.org/GTA/index.php/topic,17935.0.html

http://www.gatewaytoairguns.org/GTA/index.php/topic,20538.0.html

Quote

The receiver and bolt are plastic but all the working innards are all metal. Way to go, Daisy.

Do you think it would help if the bolt were metal?

Toolmaker · « **Reply #11 on:** December 21, 2011, 06:03:37 PM »

I tried modding an old Daisy 922 which is basically the forerunner of the SG22. The 922 is all metal including the pump arm. After all new seals, a new adjustable piston and attempted trigger mods it shoots around 550 fps on 10 pumps with 14.3 gr .22 pellets. I might have gained a little over stock but it wasn't much. IMHO the design of the powerplant limits it's upgrade potential. One idea I've been kicking around is reducing the volume of the valve to see if that will either give it a boost in fps or at least get the same power with fewer pumps.

blind dog · « **Reply #12 on:** December 21, 2011, 07:24:48 PM »

momosgarage, I can see why the bolt is plastic, actually, because it has to flex to have the snap action between open and closed. Otherwise it would need a spring loaded detent of some sort.

Toolmaker, I never thought of lowering the volume of the valve. I don't know if that would help or hurt, but it would be easy to do. That valve cover can be removed by pushing in with pliers and giving it a quarter turn either direction. The cover comes out with the stem and valve and there is an o-ring under it that pops right out. The pump cylinder just slides forward and exposes the check valve. The check valve comes out by pushing it in to take tension off its spring and pushing out its cross-pin. Then the valve chamber is all opened up.

Muppit · « **Reply #13 on:** December 21, 2011, 08:23:36 PM »

what would happen if you placed a small flat washer under the c-clip so that the hammer hit it sooner if its possable....dave

northern lights · « **Reply #14 on:** December 21, 2011, 10:38:11 PM »

The 901 880 an 22sg are easy to shoot an preyy accurate out to 25 yd,s. If you could get the 22sg up to 600 fps it would be a great hunter an its very quite conpared to the 392 an easy to scope. To bad daisy gave up on them .

blind dog · « **Reply #15 on:** December 22, 2011, 01:41:39 AM »

Quote from: Muppit on December 21, 2011, 08:23:36 PM

what would happen if you placed a small flat washer under the c-clip so that the hammer hit it sooner if its possable....dave

Probably the same result if you can find one that stays in place.

blind dog · « **Reply #16 on:** December 22, 2011, 01:49:17 AM »

Quote from: northern lights on December 21, 2011, 10:38:11 PM

The 901 880 an 22sg are easy to shoot an preyy accurate out to 25 yd,s. If you could get the 22sg up to 600 fps it would be a great hunter an its very quite conpared to the 392 an easy to scope. To bad daisy gave up on them .

Yeah. They seem to me to have given up too. They could be great, but you have to sell them in stores and not just online...and quality control NEEDS a huge improvement in my opinion. Seems like they are made in a different factory. You either get a good one or not. Daisy has good customer service. But I am tired of about half my guns, scopes, whatever from any maker being defective out of the box. Too much time and money to return things or mail them off for repairs right when you get them. Makes me not want to buy anything anymore.

My 22SG crapped out in a week. Today, I bought a bore sighter and algo a Gamo scope with the light and laser mounted on it. Both defective of course.

DavidS · « **Reply #17 on:** December 28, 2014, 03:43:27 PM »

I know that this thread is a bit old, though the info is invaluable.

When these mods are combined with the other Daisy 880/901/22X power mods it makes a huge difference in performance. Can not speak as to what single mod makes the biggest difference, though together they definitely add up to a lot more power, and yours is one of the ones that really helps.

Pellgunfun · « **Reply #18 on:** December 29, 2014, 02:14:04 PM »

So Blind Dog... where did you end up on this? Unless I missed the post, I couldn't find any before and after numbers.

Looking at what DavidS has done with his Daisy rifles, I'd say there is some real promise of performance increases to be had.

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Nearly pointless mod on a cheap Dasiy 901

Author Topic: Nearly pointless mod on a cheap Dasiy 901 (Read 7140 times))

blind dog

poomwah

blind dog

blind dog

blind dog

blind dog

northern lights

blind dog

blind dog