6 replies to this topic

[FuriousGeorge]

I'm a long time reader, but I rarely find myself posting. I only post when I have something insightful to say, or a question such as this one. I recently ordered some PETG off this site: http://www.mcmaster.com/. I’ve used it on my Nitefinder, and I am very pleased. I've found its ID to be slightly larger than CPVC, but smaller than brass. My AT2K barrels were falling off, so I replaced them with the PETG. I was astonished to find that it is almost impossible to ram the darts down the PETG. Ramming in with CPVC is much easier. It’s easy to twist them in, but beyond that is very difficult. They bend over and get stuck. I’m sure the PETG is loser than CPVC, but I can not get it down the barrel. I was wondering if this happened to anyone else, and if anyone has advice. I know FBR is nominal and different for everyone, but this situation baffled me. It shot down my hopes of PETGing an AT3K, so it looks like I might be ordering more brass.

-Furious George

[cxwq]

I don't have experience with that brand of PETG but I can compare notes with regard to the tubing I have. My 1/2" (actually about 33/64" = .515") FBR works great in my .528" nominal ID PETG. The inside is very smooth and I can either slightly twist my darts as I push them in or stretch them slightly during straightening which allows them to slide in with no effort.

If you're sure your PETG is larger ID than your CPVC but you have a harder time getting the darts in then I'd take a look at the lip on the end of your barrel. Some fine sandpaper should smooth it out and keep it from catching on the darts. I guess the other possibility is that your PETG is elliptical rather than round which would cause problems too. I don't know what you could do to solve that one other than buy new PETG.

[FuriousGeorge]

Thanks for the reply cxwq. I think you were right; it was the junk at the end of the barrel. I smoothed it out and cleaned the barrels and now they go down. The problem before was the darts were folding over themselves. I still find my brass out performs my PETG on air powered guns. I do see this PETG replacing the barrels on some of my spring guns. I’m going to test some on an X-stream. I believe my PETG might be a bit tighter than yours. Where did you order yours from, because I believe we have the same FBR (at least ordered from the same sight), so it’s helpful to know your barrel materials. Thanks for the help.

-Furious George

[cxwq]

My PETG supplier has a 1100' minimum order. At the time I purchased it, the material was not known in the community and I couldn't find anyone who would sell me a good size in smaller quantities.

I have a thread in trading where I'm selling some but my minimum is still relatively high at 100'.

[FuriousGeorge]

Yes, thank you I saw the thread. I was a bit curious of the sight you ordered from, so I could compared claimed sizes (I know you have told the actual size). Right now, 75$ is a bit too much money for barrel material, but I'm glad your selling it. I have considered buying. THanks again for the help.

-Furious George

[cxwq]

Actually the .528" is their listed nominal size. I have measured it and can say that it is within 1/64" of that size. This thread has the other pertinent sizes reported by the manufacturer as well as my experiences with it.

[FuriousGeorge]

Thanks for the help. Mine is indead a bit tighter. You have me considering ordering your PETG now. Thanks again

-Furious George