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I just got the 0.177 and 0.22 barrels. Whit the first barrel I made a very silly mistake and probably I don't have the possibility to repair it (I tried to test it with a pellet but it got stuck and I tried to push it out with a wood spike but it got stuck too. Any ideas on how to repair it? (air preassure doesn't work)) So I'm working with the 0.22 first, the problem with it is that it is way to easy to bend, how would you deal with that?

iv_meneses wrote:I just got the 0.177 and 0.22 barrels. Whit the first barrel I made a very silly mistake and probably I don't have the possibility to repair it (I tried to test it with a pellet but it got stuck and I tried to push it out with a wood spike but it got stuck too. Any ideas on how to repair it? (air preassure doesn't work)) So I'm working with the 0.22 first, the problem with it is that it is way to easy to bend, how would you deal with that?

Is the barrel a rifle steel barrel or a pipe?
Myself i removed blocked steel bbs out of aluminium pipe by inserting a metal stick ( a welding stick) and hitting it carefully with a hammer. If your barrel is made of steel it should work fine. As about the wood stick ...if it wont work pushing it from the other end with that metal stick i was telling you about .....get another pipe.......cuz anyhow you must of bent it...


If the .22 is too easy to bend, you need an outer barrel, preferable very solid one. if your barrel is not perfectly straight, accuracy is a compromise.

They are both steel 304 tubing, they are not actual barrels. Do you think that burning them is viable? They are both 1/4" OD

iv_meneses wrote:They are both steel 304 tubing, they are not actual barrels. Do you think that burning them is viable? They are both 1/4" OD

do not even heat them.....

I've had a wood "ramrod" get stuck in a barrel before too, to the point that I couldn't move it with a sledgehammer (in hindsight, that probably made it worse). Depending on how thick-walled and hard the barrel is, you have a few options.

The least likely to damage the barrel is chilling it in liquid propane or a dry ice - acetone bath. Make sure to actually fill the barrel with the coolant. If left to sit long enough, that might cause enough contraction in the blockage to allow it to be pushed out (the thermal expansion coefficient in the blockage will be much higher than that of the steel barrel). This is relatively cheap and simple, and has no potential to damage anything important. Lubricants can be used in conjunction with this method, assuming they work at -80C. If you have access to liquid nitrogen, use that - it's almost certain to work.

You could also try chemical attack. There are plenty of commonly available compounds which aggressively attack wood. Unfortunately, most of them also aggressively attack stainless steel. A concentrated, and potentially heated lye solution would be your best bet here, as most stainless steels are reasonably resistant to it. Lye will digest most organic materials, given enough time. This method will be boring, and has moderate risk of some corrosion of the barrel.

If you can acquire one of those cheap, extra-long drill bits for wood, you could try boring a hole through the blockage to relieve the stress. These drills are usually soft enough that you won't risk damaging the barrel, but they'll still cut through the lead pellet.

The most spectacular is to pressurize the barrel to something near its working pressure using a hybrid, compressed gas cylinder, etc. This has some chance of damaging the barrel, depending on how the blockage is wedged in. It has some chance of RUPTURING the barrel if you botch the calculation or pressurization method. It's what I ended up doing on my 50mm barrel due to the large size, and it worked nicely. This was at 4000psi, and the blockage cleared rapidly, in very small pieces.

Would dry ice/isopropyl 97% alcohol work? And would pvc hold the coolant during the "bath"?

It would probably work. The melting temperature of isopropyl alcohol is -89C, about 10C below the sublimation temperature of carbon dioxide. This will be more viscous than acetone, possibly by a wide margin. I can't find any viscosity data for isopropyl alcohol down below -10C, but I would assume it'd be similar to a light motor oil at -80C, based on extrapolating the curve given by the Dortmund Databank.

If that's too thick, you can try acetone, ethanol, or even propane. These obviously pose a higher fire hazard, especially the propane, and would be best done outdoors.

PVC will hold the coolant, although it will be very, very brittle at that temperature.

Flooding the pipe with acetone or ethanol before cooling it should dilute any water present and prevent the formation of ice bonding the blockage to the wall.

FYI,

Alcohol with dry ice is not very viscus at all. This is commonly used in the electrical power industry for drying large power transformers. They pull a vacuum and place a "cold trap" in the vacuum line to keep the water out of the vacuum pump. A cold trap is like a thermos bottle with a pipe into the vacuum space on one side and another on the other side. The bottle is filled with alcohol and dry ice. This traps the water vapor that could wind up in the vacuum pump. Some systems use LN2 instead, but they have a safety hazzard as they also condense Oxygen into liquid form.

Link to info on cold traps. http://www.industrialheating.com/articl ... cold-traps