SDCPs

Does it do the hop up? I thought there was a hop up system on these guns and they're so simple I'm thinking this would have to be it.

Should the hole be on the top or the bottom for best results?

borealis

To me, the hole always looked like a way to limit air depressure behind the bullet while shooting, since the stock guns are not powerful and after some travelling through the barrel (about 3-4 inches) the pushing force is depleted and turns into a braking one without that hole.

It's an air intake, basically. Shorter barrels (such as the KV-1, the Panzer III and the Panzer IV F1 dont' require it, but if you close it on longer barrels, the bullet will barely come out of the muzzle.

Ern

This has come up every now and then, and I'm still not sure of the answer. People say that it is required on the longer barrels and reduces the suction created in the barrels, etc but I have never understood why the VS tanks shoot harder with their stock aluminum barrels and they don't have any hole in them. Also, the TJMurphy modified guns with Madbull barrels don't have holes either and shoot through cardboard boxes.

Borealis, I'm not quite sure what you mean. The first part you seem to be saying that it is a safety feature as the pushing force is reduced, but then you go on to say that if you close the hole it barely exits the barrel.

The guns are basically the same... I wish HL would take a lesson from VSTank and put a slightly upgraded airsoft unit in their tanks... [>:]

Elefant

Borealis didnt write it was a safety feature, he just said it was to limit air DEpressure. The travel in longer gun is too long (meaning the volume inside the gun is bigger than the volume of compressed air created by the air gun, so without this intake, there won't be enough air to push the bullet out of the muzzle).
Check the venturi effect to understand how this hole becomes an intake.

borealis

As Elefant better explained. On VStank guns the mechanics are stronger, the pusghin sping too, the overall power of the gun is higher.

Martellus

If you can show me where it is I might be able to tell you.

Perry S.

The hole in the barrel is in fact there to keep the bb from 'pulling a vacuum' so to speak as it leaves the barrel. The volume of the plunger chamber in the AS gun is roughly equal to the volume of the breech and barrel up to the point where the hole is. It is not needed on shorter barrel AS guns.

The hole is not part of the hop up system. In fact the HL guns do not have a hop up system even though they claim to. The VS guns have one in the form of an extended tab on the rubber grommet that seals around the bb. The barrel is also notched to accept this tab. The HL guns are quite different here.

It is also obvious in the flight path of the bb's. The VS guns exhibit the hop up backspin while the HL's have a purely ballistic trajectory.

Perry

Eggman1965

My Feedback: (3)

Huh, good to know!

Mike

SDCPs

The only problem Isee with adding it to reduce the suction created in the barrels is that the plastic sleve that goes over the metal barrel might block air from even entering the hole.

Perry, thank you for the information. We all benefited

Is iseasy to install a VSgun in a Heng Long model?

One thing Inoticed:When I shimmed the stock spring, it now contacts the side of the gun for when the gun draws the spring back, the side bulges a bit. Is this normal? I don't believe the stock spring should compress nicely in a linear was if there isn't anything to restrain it. The bulging, however, worries me!

And yes, it is VERY obvious there is no hop-up (I worried that it might have been upside down, LOL)

Since I'm stuck with an airsoft unit for awhile, I'm going to be working on modding it (already built a breach from scratch) and any advice will be helpful. For those looking for threads on modding, I will repost these links. Here are two I found: 12