# Poor Mans Airsoft Chrono.

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If you every played airsoft at a field, or even with careful friends you know the importance of having a gun that shoots at the right FPS (feet per second) level. Today i will show you how to get a rough FPS reading from a soda can.

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## Step 1: Materials

materials:
Airsoft gun
.2 gram bb's HAVE TO BE .2 gram!!!
2 empty Coke-Coal Or Sprite can
Safety glasses

## Step 2: The Can

Make sure you have a un-dented Coke  Or sprite can. Other brands work too, but Coke and Sprite have the most uniform thinness.

## Step 3: Now the Tests.

Put on you glasses and gloves.
Now hold the gun about one or two inches from the gun muzzle. Be shure to keep you fingers out of the line of fire. For test one you will be shooting at the round side of the can dead center. Normal where the logo is. shoot on semi once. (almost going through dosn't count!)

Side:
One side = 290-315
Both sides=320-350

Now if you gun went threw those two sides you have to go to test two. For test two turn the can and look the the shiny side opposite to the top where you drink out of. Aim to the left or right of the cent (it will be marked in the picture). Again about one or two inches away on semi.

Bottom sides =350-375

Now If you BB went through the bottom side then you will need a new can. Flowing the same steps as above only now aim dead center of the bottom.

Bottom Center =400-450

Now flip you can and aim at the center (will be marked it picture) And follow the steps above.

Top center=450-5??

If you can go through the top not good news for the other team. Or for you if its a aeg =p.

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## 8 Discussions

the bottom side of the can is stronger than the Bottom centre would the Centre not show a low J needed to break than the sides?

How far away from the can do I hold the gun?

This doesn't measure time or distance in any sense so it's not really a "Chrono". You are using the different density and profile of the metal to gauge the ENERGY of the projectile. I don't mean to suggest that it doesn't give you a relevant set of data for comparison, just that it's not measuring what you claim (fps).

3 replies

It does not directly measure fps, but because the same mass projectile is used throughout these tests, velocity can be deduced.

Please don't confuse my semantic argument for cirtiscism of your technique. I'm actually very impressed, using the various thickness and structural features of such a ubiquitous material is inovative in the extreme, and certainly would enable you to dial your weapon into the correct power values. It is akin to a penetration test (made famous by the Mythbusters), balistic gelatin is a tricky material to work with, requiring some careful preparation and controlled conditions. A soda can is very easy, and within the limits you've pointed out, should give perfectly useable data.