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djinnform
07-31-2013, 07:01 PM
I found an Automag Dye titanium barrel on e-bay for $120 bucks. How do I know this isn't just steel or aluminum. Does anyone remember what they made or looked like? I've never seen a 2 piece like this? Thank you.

link:

http://i.ebayimg.com/t/Dye-barrel-titanium-Automag-14inch-2-piece-/00/s/MTE5NVgxNjAw/z/emEAAOxyldpR-ZX1/$T2eC16RHJIkFHRy1GbbZBR-Z(044NQ~~60_57.JPG

Ando
07-31-2013, 08:02 PM
The barrel will have a TI stamped on it if its titanium.

sniper42
08-01-2013, 01:28 PM
You should be able to feel just by weight to tell if it is stainless. Only way I know how to tell if it is titanium is if you take it to a belt sander, titanium will throw sparks where aluminum will not. I realise you probably don't want to take your barrel to a sander though. :)

Frizzle Fry
08-01-2013, 02:25 PM
You could scratch it with steel (a bastard file or something) on the haft and see if it sparks. That way you wouldn't effect functionality and the scratch would be hidden when the barrel was installed on a marker.

sniper42
08-01-2013, 06:58 PM
I don't think scratching it with a file would cause it to spark. For the same reason when you file steel it doesn't spark but when you take it to a sander it does. It needs to be a rapid material removal I think to get it to spark. You wouldn't necessarily have to sand a bunch of it. If you do the same thing Frizzle Fry recommends but with a belt sander that could work. It would be a small cosmetic mark hidden when the barrel is installed.

nak81783
08-01-2013, 08:02 PM
OP, do you have this barrel in hand or no?

If no, it should have "Ti" or "TITANIUM" stamped on it. Have the seller send you a picture of the stamp. Obviously, if you have the barrel in hand, you can simply look for the stamp as well.

If there is no stamp, there are a couple of non-destructive tests that I know about (I'm sure there are others) that can be done at a metallurgical lab, but I don't know how much a lab would charge for the testing. Many manufacturing/machine shops have these tests in-house to verify incoming material and outgoing product. If you have family/friends in such lines of work, you might want to ask if they have the equipment and could run the test for you.

1. XRF - the ones I've used are portable handheld gun-looking devices. Simply scan the metal, and it will A. give you a breakdown of the elemental composition which you can compare to the specification (e.g. an AMS spec, I'm assuming some form of Titanium alloy was used and not just pure Titanium), or B. if all the elemental compositions are within the ranges of a known material/alloy that has been pre-loaded into the XRF's software, it will tell you what it is. Obviously, you're looking for a high percentage of Titanium in the results...

2. Portable FTIR - I've only used this once, and it was on composites. But I think it works for metals too. After taking a scan, it outputs a graph of transmittance vs wavelength. Basically, the more of a certain wavelength is absorbed, it's an indicator it has that unique wavelength-absorbing chemical in it's structure. You compare that output graph to a graph of a known standard. If the fingerprints (graphs) match, that's your material. Make sure you ask for portable FTIR (the non-destructive version). There is also through-transmission IR method that requires a sample (destructive testing) from the parent material.

athomas
08-01-2013, 08:03 PM
If you had it in hand, weight would be the best indicator. Measure the displacement in water. Measure the weight. Determine the density of the material.

However, it is more difficult to determine by looking at it online through an auction. It has to be stamped or verified by some other means to determine whether it is stainless, aluminum, or titanium.

nak81783
08-01-2013, 08:06 PM
If you had it in hand, weight would be the best indicator. Measure the displacement in water. Measure the weight. Determine the density of the material.

However, it is more difficult to determine by looking at it online through an auction. It has to be stamped or verified by some other means to determine whether it is stainless, aluminum, or titanium.

I thought about the density approach, but weren't these two-piece barrels glued together? It would be difficult to get the % of weight from the Titanium and the % of weight from the aluminum.

Frizzle Fry
08-01-2013, 08:34 PM
If you could find a stainless one of the same length you could simply compare them.

athomas
08-01-2013, 08:35 PM
I never thought about the glue part. I suppose you could break down the glue using heat.

You could submerge the aluminum part, and then the back separately, vertically from each end. That would get you the percentage of each metal.

Frizzle Fry
08-01-2013, 08:51 PM
The stainless steel back would be almost twice as heavy as titanium. If you weighed an SS barrel of the same length (same size tip glued in) and the barrel you suspect to be titanium, it would be significantly lighter. I don't think it would be necessary to remove the tip.

nak81783
08-01-2013, 09:01 PM
The stainless steel back would be almost twice as heavy as titanium. If you weighed an SS barrel of the same length (same size tip glued in) and the barrel you suspect to be titanium, it would be significantly lighter. I don't think it would be necessary to remove the tip.

Buying a known stainless steel backed version of the same length for comparison might be less expensive than the tests I suggested, and then you could sell the stainless one when you're done comparing.


I never thought about the glue part. I suppose you could break down the glue using heat.

You could submerge the aluminum part, and then the back separately, vertically from each end. That would get you the percentage of each metal.

Good idea.

paint magnet
08-01-2013, 09:08 PM
If it's aluminum, it's not a Boomstick (it's an Ultralight). The titanium ones have a more grey-ish appearance and will be noticeably lighter if you are familiar with the weight of its SS counterpart...which is a brick.

Some scrap yards have electronic equipment that can analyze metals. Generally speaking they have no interest in determining what type of metal something is if you aren't planning on selling it to them though.

Obviously all of this doesn't do you much good if you don't have the barrel in hand. A twistlock barrel would have to be made out of gold for me to pay $120 for it, though.

blackdeath1k
08-01-2013, 09:13 PM
I Had a ss version back in 01. It was one heavy sob. Not as bad as my full ss barrels I used in the mid 90s though.

Ando
08-01-2013, 10:43 PM
I looked at the other pic in the sale. It def is a TI barrel

djinnform
08-11-2013, 09:23 PM
I contacted the guy and we found the "TI" mark. But, if I buy it, I'm going to grind it for sparks and do the water displacement test anyway. He's down to $100 bucks and the second re-listing on E-bay Thank you.