Dimensions for single Millbank bag ? Query for Templar

[thejungleisneutral]

Definitely scaremongering I'd say. The biggest clue was the statement that supplies of original military issue Millbank bags have dried up. We've disproven that here on this very forum, with dozens and dozens, maybe even hundreds of bags available right now in Australia at prices ranging from $8 to $20. Certainly not 22 UK quid. No doubt the Brown Filter Bag is a great product and built to spec, and it's good that if surplus stocks do dry out that they'll be available.

Millbank Bag smackdown. Post 1

What I'm doing here is running a comparison between the normal weave 1994 dated millbank bag kindly supplied by Jarrad in the recent group buy, and a 2007 dated denim-weave millbank bag I purchased at a disposals store.

Both bags have been issued, but were in brand new condition save for the previous owner's name and number. Both bags are printed with the same NSN 8465-99-973-6663 and both are made in Australia.


Photo from Jarrad's post above demonstrating the difference in the canvas weave.The newer bag is at the top and the older one at the bottom.

I've just come back from the promised muddy puddle only to find that it's dry. As an alternative I have two other sources of dodgy water -

1. A stagnant pond which was happily teeming with frog tadpoles. This water is full of particulate matter such as silt and probably tadpole faeces. It's also heavily discouloured by tannins from fallen leaves. Note that even in the best case scenario, the filter bags won't remove the colour of the tannins. Just pretend you're drinking from a pristine mountain creek in NE Tassie.



2. I filled a 10lt bucket with water and then dumped in a couple of shovelsful of soil from the garden.



Test Method:

1. Soak both bags to swell the fibres. The bags have both been soaking for about three hours in the same container.

2. Fill bag with dodgy water to the top of the bag and let drip through without collecting the water until the level reaches the line printed on the back of the bag.

3. Collect water in a suitable container and sterilise by chemicals or boiling before adding to potable water storage. I'll be boiling it.

4. Taste test.

The test will be run through a total of six times, so each bag will have its performance assessed using clean tap water, then stagnant pond water and then the muddy bucket water.

Here's the 1994 bag in the soaking container.


Next post we'll begin the testing using clean tap water and document the correct method for using a Millbank bag.

 

[thejungleisneutral]

Post 2 - the Control - Clean Tap Water

First up was the 1994 tighter-weave canvas bag.




The from the level mark to empty this bag took just over 7 minutes.

Then I performed the same test with the denim-weave 2007 issue bag




From the level mark to empty in just under three minutes.

These results indicate that the earlier ones filter more slowly than the later ones, so next post we'll test the effectiveness of each bag on stagnant pond water with a bit of silt and particulate.

 

[thejungleisneutral]

Post 3 - Dodgy stagnant pond water

I'm out of daylight so taste test will have to wait until tomorrow.

1994 Bag - Stagnant pond water


Pond water filtering into the billy


Pretty clear. No silt or debris.


Muck left on the inside of the filter. Mostly debris


Boiled to sterilize the water. I used a trangia burner and here is the billy at a rolling boil.

2007 Bag - stagnant pond water


Pond water filtering into the billy -very quickly


Also clear - no visible silt or debris


Muck on the inside of the bag -this was a surprising result since there is far more dirt, mud, silt and debris than the 1994 bag


Boiled to sterilize the water. I used a trangia burner and here is the billy at a rolling boil.

I'll do the muddy/dirty water test tomorrow.

 

[thejungleisneutral]

Post 3B - Stagnant Pond water taste test

1994 bag - Cool and clear, but a strong tannin taste was evident

2007 bag - Exactly the same as the above.

Next (and final) post will be the results of the muddy bucket water test.

 

[thejungleisneutral]

Post 4 -Muddy bucket water


Muddy water being mixed. The water was a uniform chocolate milk colour and consistency with a lot of dirt held in suspension and lots of vegetable matter floating.

1994 bag -


As expected due to the amount of mud and gunk in the water, filtering for both bags took longer than with the previous two tests.


The 1994 bag did a great job of filtering out the suspended dirt and particulate matter. I've drunk much worse, so after sterilisation I would consider this water drinkable.


1994 bag sample sterilised on the trangia at a rolling boil.

2007 bag -


As with the 1994 bag, filtering was slower than usual due to the amount of gunk in the water.


The water was a little cloudy but workable.


Sterilised by being brought to a rolling boil on the Sigg Tourist set

The final outcome -


1994 bag on the left, 2007 bag on the right.

There wasn't much in it, but the 1994 bag appears to be marginally better at filtering dirty water than the 2007 bag.

The difference is minimal, but as we know chemical sterilisation methods such as aquatabs or micropur tabs are only really effective if the water is as clear and clean as possible, which is why we use a millbank bag in the first place.

 

[Aussie123]

Excellent experiments TJIN.

Although the 1994 bag seems to do a slightly better job for very muddy water, the speed of the 2007 bag may be useful when you need to collect a quantity of water.

I'm impressed by the overall ability of these bags to filter debris !

Thanks