Cleaning Vacuum Muzzle Guns

[popgun pete]

Here is an idea for cleaning residual saltwater out of pneumo-vacuum guns which have fixed muzzle seals. The bottle-shaped gadget is used as a loading plunger with the long stem section replacing the spear and ideally being made from hard plastic. The place where the cross-bore drilling is located could be slightly thinner in diameter in order to stop the edges of those cross-bore holes damaging the muzzle seal. The cleaning operation would be as follows; you partially fill the bottle with clean water and then upend the device and push it down through the muzzle seal. As the piston is pushed back down the gun the vacuum developing in the inner barrel sucks the water out of the bottle, but if you let the bottle slowly come up then the hydrostatic pressure in the barrel pushes the water back into the bottle. A few up and down motions of the plunger will clean out the inner barrel and around the front end of the piston replacing any saltwater film with freshwater. If the muzzle seal leaks water when pushing outwards from the interior of the gun then the water is lost, but the cleaning action will still be the same. Also if you let go of the bottle then the water will push the stem out, so you need to keep a good grip on it, but the stroke will be small, so not likely to be dangerous in terms of the bottle flying out of the gun.

 

[tromic]

I suppose pressure in a gun have to be lowered so you can push the piston with plastic tubing? I prefere to depressurize the gun and remove the muzzle so I can rinse it in tap water, before longer storage.

When gun is on working pressure I would do something similar to your advice. I would take a 15 cm long piece of the shaft (tail end) and make it one side flat so it wont seal. With shaft in a muzzle I would submerge it in a bucket with tap water using pumping actions few times.

 

[popgun pete]

I suppose pressure in a gun have to be lowered so you can push the piston with plastic tubing? I prefere to depressurize the gun and remove the muzzle so I can rinse it in tap water, before longer storage.

It would not be plastic tubing. The stem would be a rigid plastic rod drilled out to create the small bore hole. A similar plunger made of plastic was used on Nemrod guns and was able to push the piston back even with the gun at full pressure. The diagram is only a schematic, the detail could be different, for example the plunger could have loading "ears" on either side and the water container on top of that. Manufacturers could make this as an accessory using moulded plastic parts.

 

[tromic]

It would not be plastic tubing. The stem would be a rigid plastic rod drilled out to create the small bore hole. A similar plunger made of plastic was used on Nemrod guns and was able to push the piston back even with the gun at full pressure. The diagram is only a schematic, the detail could be different, for example the plunger could have loading "ears" on either side and the water container on top of that. Manufacturers could make this as an accessory using moulded plastic parts.

Pete, that is very useful device to prevent corrosion due to salt water in vacuum barrel guns.
My solution is "upside down" your solution.

 

[popgun pete]

Pete, that is very useful device to prevent corrosion due to salt water in vacuum barrel guns.
My solution is "upside down" your solution.

A wider base or pad under the spear may be necessary, when I tried that during my "quick and dirty" vacuum barrel experiments I nearly pushed the spear (without tip) through the bottom of the bucket! An old engine valve may make a good plunger with the stem turned down to size and the wide valve head serving as the base.

 

[tromic]

A wider base or pad under the spear may be necessary, when I tried that during my "quick and dirty" vacuum barrel experiments I nearly pushed the spear (without tip) through the bottom of the bucket! An old engine valve may make a good plunger with the stem turned down to size and the wide valve head serving as the base.

Yes, that idea using valve is good! :friday

 

[popgun pete]

Another version of cleaning gadget for vacuum barrel guns where you can unscrew the nose end of the muzzle and remove the vacuum seal while leaving the gun still pressurized. Example shown here is the STC X-Power, but could be any unit using this type of layout. Essentially a water filled cup screws on top of the muzzle, then you pump the spear up and down in the gun which sucks water back and forth in the barrel and cleans out around the piston nose and the shock absorber.

 

[Diving Gecko]

I actually do that, kind of, with my One Air.
I take it to the shower with me and unscrew the cap (there is a thin o-ring, that you don't wanna loose) and then I push the spear in a bit.
I don't need the water reservoir on the top as there is a constant water flow from the shower head.

But the idea of getting a small piece of rod to use for this purpose is very good. For a second I thought that a 7mm stringer could do the job (you'd put a loader handle on the pointy end) but I think A). it may not be long enough and B). the line in the middle of it is going to be an issue. It would just have been cool not to have to add another piece of gear to the set.

 

[popgun pete]

Well you don't have to push the piston back that far, so a short rod would do, as the piston seals wipe the inner barrel except for the last section which is the length of the piston nose in front of the first (and maybe only) seal on the piston. A few inches would probably be enough.

 

[popgun pete]

When you cannot find something it is sometimes best to stop looking and let it find you. A case in point is this little green plunger made for pushing back the piston on Nemrod guns in order to introduce drops of oil into the muzzle. The reason being that Nemrod and their emulators for a long time had ports in the wrong place on their muzzles so that washing the gun in a tub never got behind the anvil, hence the length of inner barrel forwards of the front piston seal with the piston leaning on the anvil was unwashed except for water that got in via the tiny holes in the side of the piston nose. Note the rust on the front end of the pistons! It was memory of this device that started my train of thought on cleaning out the muzzle of pneumo-vacuum guns as they don’t have any muzzle relief ports, or holes in the sides of their pistons!

The other gadget is a muzzle plug for when the gun is in storage, if you were smart you never used it as such as you locked any residual water in the muzzle if you never did the muzzle oiling. As few owners ever read instructions this gadget was probably tossed in a drawer to be completely forgotten until their gun seized up.

 

[omega3]

Heh heh saltwater 1 speargun 0. Thanks Pete. Seeing all this work makes me think I will just tack a bit of zinc on somewhere and hope for the best!

 

[tromic]

I suppose pressure in a gun have to be lowered so you can push the piston with plastic tubing? I prefere to depressurize the gun and remove the muzzle so I can rinse it in tap water, before longer storage.

When gun is on working pressure I would do something similar to your advice. I would take a 15 cm long piece of the shaft (tail end) and make it one side flat so it wont seal. With shaft in a muzzle I would submerge it in a bucket with tap water using pumping actions few times.

This summer after finished using my Cyrano 850 in a salt water, I used this method slightly modified. I had loaded the speargun, prior unscrewing the trident, and switched to low power. After I submerged the gun in a bucket with tap water having the tip of the shaft on the bucket bottom and activating the trigger I did few times pumping action having the muzzle submerged.

 

[popgun pete]

Most vacuum barrel guns these days have removable vacuum seals, but water will still trap behind the anvil of the shock absorber which sits behind it. You can take the vacuum seal out first and then carry out the muzzle cleaning using a short stroke pumping tool which will eliminate any possibility of damaging the rubber sealing lip.