MY Modified Bulldog is Leaking Air

[Airgunhunter73]

Well fellas went to the range today for a little shooting here's some pics of the Bulldog at 25 and 50 yards, they kept the 100 yard line filled up today so I'll try for next week.

[Kinetic45^]

are you weighing your bullets?
I found that having all the bullets weigh within 1 grain on a 148gr bullet  to helps tighten groups in the big bore airguns.
this is especially true to find and cull light bullets that have void bubbles inside the bullet because not only will they cause a point of aim shift in impact from the different weight being propelled/launched inside the barrel by the air they will not fly true being off center in rotation , like a tire out of balance.  And the longer the distance the more they become fliers

[Airgunhunter73]

I usually weight my boolits but I don't think I had done that with these 148gr HPs and the 130 grainers were given me so I forgot to weigh them also, thanks for the advice I learn something about this sport all the time reading the posts you fellas write about your experiences they are so helpful Thank you .

[Jzizzle]

To add to someone else's issue with burping.
My bulldog with jsar valve is exhibiting this issue with each shot which causes 800-1000psi per shot.  I was sent a new poppet but the same issue persists.

Anybody know how to resolve this issue?  Very frustrating.

[Kinetic45^]

I did change o-ring lube on the poppet to the Ultimox 226 lube and that seemed to help. I really think the poppet stem is binding a bit on some rifles and causing hammer bounce.

But I also changed the spring after talking with Oldpro on the phone about changing the orifice to get a different curve and he mentioned taking the stock spring and cutting TWO COILS OFF and using it.
I had occasionally gotten the burping but since modifying the origional spring it's never happened again.
But I can't say which was the solution since I did both at the same time.

FYI - I get a higher FPE first shot but then a declining string, not as flat a curve as with the SS valve spring.

NOTE - he warned me that using the factory Bulldog spring full length would destroy the poppet fairly soon.  It has to be shortened.

Call JSAR, Travis is a good guy and will help you.  He's helped me on several Marauder issues and with the Bulldog/Pitbull issues as well.

[Jzizzle]

JSAR sent me a replacement poppet but it didn't solve the burping issue and still wastes air.  Still hoping to hear back for a solution.  Any ideas of what the problem could be?

[gendoc]

JSAR sent me a replacement poppet but it didn't solve the burping issue and still wastes air.  Still hoping to hear back for a solution.  Any ideas of what the problem could be?

send it to matt & paul @ pitbull airguns, they will get it right !!
the previous owner of mine said it came from that direction and had problems....
i sent it to matt and now its a great shooter with much more power and consistancy

[Jzizzle]

Well I have since removed the SS valve and installed the original OEM back and no more burping issues.  I'd prefer not to send the rifle off as the issue is 100% in the jsar valve.
I was hoping to get a replacement but unfortunately weeks have gone by and I haven't heard anything back. 

[Kinetic45^]

Which hammer spring were you using with the SS valve? The JSAR one or the 2 coil cut off Benjamin one?

As I said in an earlier post, I am getting good performance with the SS valve and it's no longer burping BUT I had to go to the modified spring.

Pitbull does not recommend using the SS valve as they could not get it to shoot consistently BUT those of us who have tried it in our Pitbulls WITH the right stem polish, stem and poppet lube and hammer spring mod are not having problems any longer.

[Jzizzle]

Ive used both the supplied jsar and OEM cut.  Both springs exhibit same burping issue.  Brand new poppet did not fix the issue either.

[Jzizzle]

To add to previous, burping issue with SS Valve began after approx 800 shots.

[Kinetic45^]

Hummm
One last 'fix' is to take out the jet on the valve and use a drop of solder to close the hole then redrill smaller which is another thing I discussed with Oldpro but did not have to do as my problem was fixed with the other steps.
{Or buy a new one, I think it's a watercraft or snowmobile jet?}
Don't remember the size he recommended, call him / Travis to get it, he really treated me well on this issue.

And my Pitbull probably has very close to 2000 shots since I installed the SS valve and solved the burping issue.
[ I shoot 4ea, 60 min SCBA tanks down each week at the range on average.  Have to buy 40 lbs lead every month to keep up with the casting/shooting!]