Picked up a nearly new Benjamin 392 at a gun show last month. Been wanting one (or a Sheridan) for some time now.
Anyway, got the gun home and started to "play" with it. Pumping it was a lot harder than I had thought it would be. And it didn't seem to be too accurate. Bummer. No wonder such a new gun was for sale.
Well, I searched the forums and found answers to my problems. First was the accuracy problem. Found that late model guns have paint build-up in the muzzle. Carb cleaner was recommended to clean up the offending overspray. I sprayed some on a Q-tip and started scrubbing. Used a .22 barrel mop too. Finally the Q-tips and patches came out clean. Shot a whole lot better. Then I polished the crown. Now it SHOOTS!! And it seems to really like the cheap Daisy wadcutters from WalMart too.

Also re-shaped the front sight to more of a Patridge profile. The gun is more accurate than I am with the open sights. And the original rear sight was tweaked a bit too to get the gun on target. These are some of the best sights for my vision. The rear sight is far enough forward I can see it clearly.
Found a page showing how to polish the sear to improve the trigger pull. A little work with some 320 grit paper and some moly grease took care of that issue.
Next came the pumping. After 15 minutes of shooting (at no more than 5 pumps, usually 3) my left shoulder was killing me. Something had to be done. Found a solution on a certain "lemon-colored" forum. Open up the valve. Cut down the size of the check add a small light spring behind it and a washer. Then clip a couple of coils of the exhaust spring and put in on top of the washer. Then put the valve back together. Don't screw the two halves together too tight. You need to be able to see some of the O-ring. This makes the valve a little longer and closes up some of the pump headspace.
Now the first 5 pumps are as easy as a 1377 and seems like it may be making a little more power than it did when I first got it. I need to get a chrony one day and see what this gun does.
A little time researching the net and tinkering transformed the so-so airgun into a sweet shooting carbine.
