Carbon tetrachloride
Hi all
I thought I'd put my two bits in (okay, another essay, but I care about your health) about the safe use of solvents for reloading since it's come up. I use solvents of every variety every day at work and I've just set up a new lab for a new employer where I've almost entirely eliminated the use of dichloromethane (DCM, 1 carbon, 2 chlorines, 2 hydrogens). It's like carbon tetrachloride (CTC, 1 carbon, 4 chlorines). This isn't to pick out the use of CTC but to give some advice about getting rid of oils from brass. Oils kill primers faster than anything else you'll come across reloading.
Some of the suppliers I've dealt with asked "you're still allowed to use DCM?!?"
Like CTC, it does such a good job. It mixes with other solvents, dissolves stuff, won't mix with water. It's denser than water, but when I mix 30% dichloromethane and 70% hexane (similar to gasoline) it separates and floats on water. Great for extracting solvent soluble things from water (like drugs from blood or urine in my job). Just take it off the top and dry it off. Use chlorobutane if you don't want to blend solvents - it's the most chlorine you can put into a solvent and still float on water.
DCM evaporates quickly - it's boiling point is just above body temperature. Doesn't burn readily - strange for such a volatile solvent. When it does burn it decomposes into phosgene, a chemical agent popular in WWI and Northern Iraq. Nice. Latex gloves are not fully protective - wear nitrile (and glasses - always wear glasses with just about everything - you only go blind once). And use it in a fume hood - if your environmental agency lets you use it at all.
Andy - you're right about carbon tetrachloride (CTC, 1 carbon, 4 chlorines) - don't ingest it in any way, but where does it go when it evaporates? It doesn't absorb well into activated carbon filters. Please don't quote me and I'll stand corrected, but something like 1 kg (2.2 pounds) of CTC destroys something like a ton of ozone. CTC is also much like chloroform (1 carbon, 3 chlorines, 1 hydrogen). It's not used for general anaesthetics any more, just in the lab.
I use gasoline for cleaning oils from cases. It does a great job and as far as solvents go it's really cheap and clean, cheaper than thinners, and it's the oils that stop primers from going off and powder from burning. I've used acetone (old formula nail polish) with similar success, but it costs more. Acetone is also good for helping dry wet cases since it's miscible with water (but not in the oven!). And it won't give you cancer or destroy the ozone layer. Just don't pour it down the drain when you're done. ;-) Leave it to evaporate outside and away from an ignition source when it's too contaminated to reuse. Luckily for me I've got another couple of litres of acetone from the lab that was recently used to clean the electronics from a mass spectrometer. Still perfectly good to sonicate brass! Ethyl acetate (new formula nail polish remover) is good, but isn't completely miscible with water like acetone.
Reloading is fun and should be safe well into your cancer free old age. And leave some atmosphere for the grandkids to inherit.
Regards
Ben