Paintball

[B.R.]

got a sentinel in the mail i bought on ebay today.
it isnt recocking, i tried a couple different o-rings on the hammer
one of wich was the same size as the one i took off of it.
im thinking it may have been a little thin anyone know a number or size for the hammer o-ring?
the main spring in it was blue and reminded me of one out of a spyder kit.
i ordered up a madman spyder kit and some spyder shims.
will that stuff work?

the gun is a am-4 it seams real sturdy and well machined im kind of pumped to have a good recball gun to run on co2
thanks for any help

[flyweightnate]

Will it recock by hand? The sears can wear out.

Also, unlike a Spyder the 'bumper' is merely an oring on the bottom tube plug (which in this case is probably part of the stock). There should not be a donut around the spring. If this oring is missing, it can actually cycle too fast and miss the sear, as well.

Check the valve pin, to ensure it is ground flat on one side like a Spyder valve pin, instead of completely round like an Autococker valve pin.

If none of this helps, your pressure or springs are the problem, or the sear or hammer is worn out.

[B.R.]

thanks for all that nate.
the valve is installed in the right direction correctly for sure and the pin does have a flat spot.
it doesnt have a bumper like a spyder or tippmann around the main spring.
it will cock by hand and hold i dont think it is bouncing back at all.
actually when i first aired it up it recocked fine but the bolt was in upside down
of course the balls only made it a couple feet....
ill have to monkey w/ springs once they come in, and im not that confident that the hammer o-ring is right

[desertT1]

What pressure is the tank that you are using, unless you are using a co2 tank. If it's a lower pressure tank, you might not have enough pressure which is why it worked when the bolt was upside down.

[B.R.]

i was using c02 ill have to try it w/ air or i could throw a stab on it.
i see what you mean though. i wondered if the valve wasnt opening long enough but to low of pressure would make sense i just filled the tank

[flyweightnate]

Higher pressure is better for recocking... almost always. 600psi is the "ideal" for these guns. The ones I'm selling operated great there for years, and never have recock issues. How oiled is it? I like mine to be a bit on the dry side, except the hammer o-ring.

[B.R.]

got it rocking yesterday. heavier main spring and a lighter valve spring
shoots around 290-300 unregged co2
with no tension on the valve spring