I´ve purchased an oldie .177 Diana 35 some time ago. It is almost new, shooting a 7 gr pellet at 750 fps. I´ve noticed that it shooted quite twangy, with some vibration. Then I put the J. Maccari Velocity Tar grease in its spring, and it shoots with less vibration now, but still with some.
There´s a Pyramid air report about the 27 (this gun is really smooth) and the 35, and it talks about the vibrations in the 35 firing cycle.
Question: is it usual that the 35 shoots so twangy ?. How can I fix it ?
Larger volume than a model 27 and twangy. Yours shooting 725 - 750 with normal pellets is a little hot. Might have some lube on the seal that's burning off. Mine is right about at 700 fps.
To get them nice and smooth, you've got to polish the piston and lube the piston/spring with moly and tar. It also helps if you put some buttons on the piston. The biggest improvement will be from installation of a top guide. To get one fitted you will need to measure the exact ID of the spring and then cut material from the bottom guide of equal thickness to the top guide thickness to allow thegun to cock.
"but I'll be needin' that gun, fer squirrels and such."
I agree with a piston polish and some buttons. I think that little bit of twang is also from the stock spring guide. I tighter fitting guide will smooth that right out.
