Benjamin 392PA woes..

[tennx]

I believe this is a 2014 gun....has always shot in a consistent 4” circle..never dead center....no matter how I scoped....folks recommended I clean the paint off inside ...still no love...Ive learned to live with it. But .now its taken to shooting low velocity and spitting pellets about every 4th shot...heck I even had a couple just slide out after a couple pumps....its not one of my go to shooters but would like it to work...opinions....TIA

[Habanero69er]

Phil, what pellets are you shooting?

[tennx]

Phil, what pellets are you shooting?

At the moment Crosman  premier domed ultra magnum 14.3...but the random targeting has been ongoing with several different styles..thanks

[Psipumper]

I believe this is a 2014 gun....has always shot in a consistent 4” circle..never dead center....no matter how I scoped....folks recommended I clean the paint off inside ...still no love...Ive learned to live with it. But .now its taken to shooting low velocity and spitting pellets about every 4th shot...heck I even had a couple just slide out after a couple pumps....its not one of my go to shooters but would like it to work...opinions....TIA

At what distance do you get a 4 inch circle?
If a pellet came out of the barrel when you were pumping , air is leaking past the front oring when pumping. This air travels to the transfer port leaking into the barrel instead of going into the valve.
The valve would need to be removed and the oring replaced. I would try 5 or 6 wraps of Teflon tape in the oring groove under the oring to tighten it up.

[tennx]

What is the chance of it being the pump cup...air getting pass on pumping and not building pressure....I have no problem rebuilding the gun..if needed ...thanks

[35 shooter]

Pump cup was on my suspicion list when I read your post, depending on how much it’s been fired over the years.

Having said that, anytime I’ve had to go into my 392’s or 397 to fix any kind of leak... I just replace everything while i’m In there just to be sure.

As to the accuracy problem your having... I have a 397 that won’t shoot anything i’ve tried so far except beeman pointed pellets.
I also have a 392 that has’nt shot anything well except gamo magnums and the jsb 16 gr.
On the other hand I have a new to me 392 that shoots anything i’ve put through it so far extremely accurate.

Some of the 39x guns can be very pellet picky.

[avator]

Phil..
Does the pump handle feel like it has pressure on it pushing it back open when you go for stroke 2, 3, 4,  ect?

[avator]

…. also, have you tried cocking the gun before you pump it?

[tennx]

Pump cup was on my suspicion list when I read your post, depending on how much it’s been fired over the years.

Having said that, anytime I’ve had to go into my 392’s or 397 to fix any kind of leak... I just replace everything while i’m In there just to be sure.

I like the way u think.....gun pumps and holds air eventually...as to the targeting ..35 to 50 feet holds the same random pattern...inside a 4-5 inch circle all over the place ...since I just kill cans ...live with it...

[tennx]

…. also, have you tried cocking the gun before you pump it?

DOH!!!!..no...but this problem just started...

Actually just tried it ...wouldnt hold air at all...lol...I’m thinking a good gutting is to be scheduled...thanks

[35 shooter]

Phil,

On the accuracy problem... have you checked the crown?
Or maybe for tooling marks inside the bore?

[tennx]

Phil,

On the accuracy problem... have you checked the crown?
Or maybe for tooling marks inside the bore?

I called myself cleaning the paint out...no obvious damage...gun was bought used...has never been bulls eye accurate...and Ive had a variety of scopes...I guess I could try a peep....obviously more concerned about pumping problem....not a real big problem....Not to brag but I got like 30+ rifles and pistols...lol...thanks

[avator]

Yup, I think start with a reseal.
IMO... that paint in the barrel thing has been a bit embellished.... not like I haven't been wrong in the past. I can only go on my personal experience.
Consider this.... pumpers have a built in power adjustment... this is controlled by the number of pumps we put in it. POI at 3 pumps will be different than POI at 8 pumps... depending on range, of course. Now, if you have a leak or cup seal blow by, you won't be consistently putting the same pressure in the valve from shot to shot. Inconsistent pressure will affect POI.
I asked about the back pressure on the pump handle... if that is present then I would have a look at the check valve in the valve. Maybe not sealing.
PA indicates Pump Assist. If I'm not mistaken, Pump Assist means it has one spring in the valve as opposed to the 2 spring with a washer between them of years prior.
On another note, you said the gun was bought used. There is no telling what the previous owner lubed the gun with.... if at all.
Have you considered an alcohol flush?

[tennx]

Phil..
Does the pump handle feel like it has pressure on it pushing it back open when you go for stroke 2, 3, 4,  ect?

Apologies I overlooked this post...first off if it matters gun has been sitting for at least a year with 2 pumps....I just discovered that if u ease the pump handle down ,zero pressure...but if u pump rapidly pressure builds...as for the alcohol flush...I know it works for others but....I gave my brother a 392 and it quit building pressure...so I called myself doing the flush...well I fubared that...so for his gun ,new valve ,pump cup and a Mr. Mellon pivot set....I won’t try flush on this gun...I have the tools and some of the talent...when I get to feeling froggy will do the same to this gun...............and maybe swap a peep on it....many thanks for all the replies

[avator]

Good luck Brother Phil.... we're here if you need help.

[ray1377]

Phil

Just saw this post and might I add a small bit of information here that might save you some grief down the road later.
I have a 392 and a few years ago it got to acting weird while pumping it up. I would begin to pump and sometimes, not every time around pump 3 or 4 it would out of the blue discharge the pellet out of the barrel with enough force to scare the $#!+ out of you. The first time it happened the pellet bounce off a steel beam in my garage. I thought at first I must have hit the trigger by accident. But oddly enough after the discharge the hammer was still cocked. Turns out that after putting 3 or 4 pumps into the valve brought the pressure up enough that the next pump sometimes would not open the check valve but was actually going past the front valve o-ring and exiting out the transfer opening sending the pellet out the barrel. After replacing the valve o-rings this problem went away.
But as a safety precaution on "ALL" my pumpers now I never load and close the breech before pumping. I've made it a habit to cock the gun then pump it up with the bolt still back and barrel open, then after pumping load the pellet and close the bolt.
I think that is a good practice for everyone to do when dealing with pump airguns. Can't ever be to careful.
Hope you get your benji all resealed and shooting like new again.
Thanks
Ray
P.S. If you live in Memphis I'm  only about 65 miles south of you , maybe after this covid thing blows over we might get together and shoot sometime?
 

[tennx]

Phil

Just saw this post and might I add a small bit of information here that might save you some grief down the road later.
I have a 392 and a few years ago it got to acting weird while pumping it up. I would begin to pump and sometimes, not every time around pump 3 or 4 it would out of the blue discharge the pellet out of the barrel with enough force to scare the $#!+ out of you. The first time it happened the pellet bounce off a steel beam in my garage. I thought at first I must have hit the trigger by accident. But oddly enough after the discharge the hammer was still cocked. Turns out that after putting 3 or 4 pumps into the valve brought the pressure up enough that the next pump sometimes would not open the check valve but was actually going past the front valve o-ring and exiting out the transfer opening sending the pellet out the barrel. After replacing the valve o-rings this problem went away.


But as a safety precaution on "ALL" my pumpers now I never load and close the breech before pumping. I've made it a habit to cock the gun then pump it up with the bolt still back and barrel open, then after pumping load the pellet and close the bolt.
I think that is a good practice for everyone to do when dealing with pump airguns. Can't ever be to careful.
Hope you get your benji all resealed and shooting like new again.
Thanks
Ray
P.S. If you live in Memphis I'm  only about 65 miles south of you , maybe after this covid thing blows over we might get together and shoot sometime?

U pretty much described exactly what mines doing and did a heck of lot better explaining it ....many,many thanks....will be getting=ing my parts order ready.....look forward to maybe getting together...