Using a 6 inch (or larger) diameter PVC pipe sized to fit your stainless steel guns, you can use two of these low cost flexible PVC caps to cover the ends: http://www.amazon.com/Fernco-Inc-PQC-106-6-Inch-Qwik/dp/B000VZPZNG?ie=UTF8&psc=1&redirect=true&ref_=ox_sc_act_title_2&smid=ATVPDKIKX0DER
An advantage, or possible disadvantage of this model is that the metal hose clamp would be easily found with a metal detector. It could also rust and be hard to get off or even break and fall off over time making it ineffective. So I might limit this to a shorter term, lower cost alternative.
Another alternative are these slip/glue on caps that can be used on one or both ends: http://www.amazon.com/Genova-40156-Cap-Sewer-Drain/dp/B000BQPAJ4?ie=UTF8&psc=1&redirect=true&ref_=ox_sc_act_title_1&smid=A1SV1BYDTUK2Z5
A more expensive alternative is to use on of the above glue on caps on one end, and these two items on the other end for a screw on/off access:
These two combined look like a common sewer clean out port and can be installed in plain sight and still look normal. They are also likely to last the longest.
There are also off the shelf Burial Tubes for firearms that are available like this one, but remember that PVC has been used for underground pipes for many years because it lasts the longest.
Including some desiccant to absorb moisture along with some of the long term storage bags might be a good idea. Be sure to bury them in a location that you will be able to find them for many years to come, and share one but not all of your locations with different trusted family &/or friends. Keep a record of who you shared each one with for obvious reasons.
Here are some of the things you can store in a PVC Burial Tube:
- Take down Stainless Steel 22 caliber survival rife (Marlin or Ruger).
- Stainless Steel Revolver
- Ammo with Chrome/Nickle plated casings if possible.
- Gun oil
- Old US silver quarters and dimes
- Magnesium fire starter
- Water straw filter
- Para cord
- Stainless Steel Knife & saw
- Fish hooks (plated), steel leaders and braided fishing string.
- Small survival blanket
For some additional ideas on what to pack see the following video: Wilderness Survival Pack
For additional information see the following links:
Here are some additional links for building a PVC burial tube: