888 gas leak?

dhurt · Post by **dhurt** » Wed Jun 23, 2010 6:01 pm

Our 4-H club has 4 of these rifles and we can keep 50% of them running. Daisy has fixed two of them already. With three recent returns, the next rifle is now malfunctioning, after loading, pressure drops off dramatically. The longer you wait the less it has, though it does'nt lose it completely. Does this seem to be something that is easy to fix, or should I send the rifle to Daisy? They have been easy to deal with, though I would like to be able to keep these things running myself. Thanks for the input, Dwaine Hurt.

silentfury214 · Post by **silentfury214** » Thu Jun 24, 2010 9:16 am

I don't know how relevant this is, but is the o-ring on the gas cylinder intact?

SRichieR · Post by **SRichieR** » Thu Jun 24, 2010 10:35 am

I suggest the following:

1. Is gas coming past the valve and out the barrel? If so, that is generally a Daisy problem. I have had limited success cleaning the valve. Worth a try. The valve in the receiver can not easily be replaced.

2. Is the co2 cylinder filled properly. The ONLY way to know is to weigh it. If not filled properly, the pressure will fall rapidly and with every shot.

3. Are the cylinders leaking. Fill it, submerge in water and look for bubbles. Sometimes the brass fittings leak. I've also had the rupture disk on the end develop a slow leak.

4. As mentioned in previous post, is the cylinder oring intact? If there is a noticeable leak when assembled it pretty much must be the oring or the valve mentioned in item 1 above.

jhmartin · Post by **jhmartin** » Thu Jun 24, 2010 2:23 pm

SRichieR wrote:I suggest the following:

2. Is the co2 cylinder filled properly. The ONLY way to know is to weigh it. If not filled properly, the pressure will fall rapidly and with every shot.

Sam is spot on here .... you must weigh the cylinder.
I place them in a freezer for a few hours and then fill. My goal is to get them between (total weight) 460 & 475 grams ... you should be able to easily fire 2 3x20 matches with a fill like that. An empty cylinder is about 400-405 grams

It does seem like you've underfilled these

dhurt · Post by **dhurt** » Fri Jun 25, 2010 2:17 pm

Howdy, I will clarify. The co2 cylinder is full. If i open/close the bolt and dry fire, I get a nice puff of co2. If I wait 30 seconds, I get a small puff of co2. Shots drop from 1 to 2 bulls low on the multi targets. Thanks, Dwaine

jhmartin · Post by **jhmartin** » Fri Jun 25, 2010 2:40 pm

Well ... again what is the weight of the cylinder? .... an overfilled cylinder can cause this is there is too much "liquid" that goes thru the valve and "freezes" it....
If you let the rifle sit for say ... 10 minutes and fire again do you get a good shot? If so, then again my guess is an overfill

Also what it the temp you are firing in .... indoor/outdoor?

dhurt · Post by **dhurt** » Tue Jun 29, 2010 5:26 pm

Howdy, I have been running 70 grams, 72 degrees, indoor, 65% humidity. Thanks, Dwaine

jhmartin · Post by **jhmartin** » Tue Jun 29, 2010 7:31 pm

Hmmmm.... 470-475 total weight right?

Well it sounds like this needs to go back to Daisy to me.

One more thing you can try ... take the rifle trigger assy apart and stretch the hammer spring about 1/8 to 1/4 of an inch more in length. No more as then it is diminishing returns and it's tough to get that thing back in. Measure it before you stretch it.

Sometimes if I have a rifle shooting slow, this will get it acting nice again.

dhurt · Post by **dhurt** » Wed Jun 30, 2010 8:01 am

Thanks for your help! I will try the spring stretch. Thanks again, Dwaine.

Bntarrw · Post by **Bntarrw** » Tue Nov 09, 2010 4:01 pm

Sound like to me the plunger spring in valve assy. under the co2 clyinder.