A Few Notes On the V-350

I reassembled the V-350 with a new o-ring but reused the other two seals

I decided to sand the rust out of the barrel.


Still splotchy…I kept at it.


At least the lettering is still intact.


Barrel and tube were reblued with Van’s cold blue.


I still don’t completely understand the gun. But this pop valve feeds the BBs into the barrel from the flat and channel above.


Fed.


I had to debur the end of the barrel. I found that the BBs were shooting out at a 45 degree angle – there was a dent at the end diverting them. I wish I’d noticed it when I had the barrel in the lathe…

I had to disassemble it again though as it was only doing 175fps and it should be doing 350fps (hence the V-350).


The manual said to use thread sealant on the barrel threads, so I uses some teflon tape. The spring seems canted (sorry, no pic.) which could also be part of the problem, more so if it’s also become a bit relaxed. But I reassembled it and it’s now shooting between 185 and 240 fps. That’s an annoyingly large spread of velocities which was compounded by the fact that I think the chronograph has a hard time seeing BBs on a sunny day. I received many of the dreaded Shooting Chrony “ERR” messages. To further muddy the waters it seems as though trigger release plays a large part – which means that things are dragging on other things in an unpredictable way.

So I’ll have to think about things. Spring, seals and more smoothening seem in order. Unfortunately I’m not sure what to do about the first two. I might preload the spring a little, if there’s room. We’ll see.

Well Derrick's been posting up a storm, so I messed with it a bit more...

I made a spacer for the spring.


The spacer adds about .2" of thickness...So I put it back together again and found almost no
change in velocity. At least I figured out that the lenses of the Chrony were dirty - cleaning them helped getting better readings. This leaves it at the seals or some other unknown problem. I'll have to think on it for a while. It may still be that the spring is too weak but it does seem as strong as it should be for a non leveraged cocking gun.

Crosman V-350 BB Gun Disassembly, Part 2

On I go

I had to pump up the contrast to show the stamping on the barrel.
V-350 SLIDE ACTION
I probably should mention that you cock the rifle by sliding the barrel into the action...but more about that if/when I get it working...


Removing the front sight.

The threads are minimal, as the rust gives way.


The trigger guard is removed with two screws.


Punching out the trigger pin.


The trigger/sear is pulled out.


Trigger/sear, pin and spring.


The ball…it's the "barrel lock" so it presumably locks the barrel.


I carefully levered it out.


There’s a spring underneath.


The ball and spring.


Removing the piston seal. It stretched and came off. I’m not sure how to replicate it. I suppose I could try and reuse it but it is a bit scarred.


The hammer and piston assembly. The manual shows it as two pieces but as far as I can tell it’s one piece.


The "pop" valve cleaned up.


I removed the seal. It seems to be nylon.


The felt and o-ring are both toast.

So now I have to clean everything and try to reassemble it. I don’t know if the seals can be re-used. If I have to fit a new piston seal I may try an o-ring or make a copy of the teflon seal from polyurethane. Or I may try teflon. I will still need to examine the piston thoroughly to see if it could possibly be two parts.

Crosman V-350 BB Gun Disassembly, Part 1

I picked up this rusty Crosman V-350 BB gun a while back. It functions but is in rough shape.


The barrel is extremely rusty.


Two screws fore and aft remove the stock from the action.


Hmmm, a ball bearing. Crosman doesn’t have an exploded diagram or manual on their site but there are instructions here in the Crosman Service manual. (Very handy PDF!)


Another shot of the ball bearing and spring.

A band clamp is used as the front stock mount.

Knurled nut retains the barrel. It is called the "Tube Bearing" as the barrel slides into it.


A post (locating stud) for the rear stock screw also retains the spring. This is a spring piston gun, although a somewhat unusual one.


Another shot.


I think the rear sight is misaligned.Again you can see the rust.


Put it in the spring compressor.

Knocked the pin out.


Spring and cap. (Tube Plug and Stop Assembly).


The piston assembly, spring and cap.


Teflon seal.


It appears to be one part, unlike the drawing in the service manual.


Unscrewed the barrel retaining nut/bearing.


Unscrewing the hollow screw that guides the barrel.


The hollow guide screw.


A small ball bearing and spring are revealed in another hole when the barrel is rotated 90 degrees.


A spacer sleeve around the barrel.


The seal for the barrel. "Barrel cap".


Barrel sleeve/bearing and spacer and barrel.


The seal assembly has a pop valve.I’m nut sure why it’s so complex and to be frank I don’t think I will understand the entire mechanism until I have cleaned it all up and reassembled it.


The barrel cap is a somewhat complex part.


Inside. More to come…