5/16 Barb Size Differences

[kclebak]

I am making a return to home brewing after being away for many years. This time around I am moving straight to kegging as I used to bottle previously. Thus, I am new to Kegging and CO2 regulators and have a question on barb sizes. I have a taprite primary CO2 regulator and a taprite secondary CO2 regulator. The primary regulator is equipped with an MFL check valve and came with a both a 1/4-inch and 5/16-inch barb and swivel nut. The inlet on the secondary regulator is a 5/16 barb. While minimal, you can see that the 5/16 barb on the inlet of the secondary is slightly larger than the 5/16 barb with the swivel nut. It's even more noticeable when connecting 5/16 ID gas line to the two. It goes on and off the 5/16-inch barb and swivel nut fairly easily, but you have to really work it on and off the 5/16-barb inlet of the secondary regulator.

I did confirm that I was using the 5/16-inch barb and not the 1/4-inch barb that came with the primary. I am just curious if this is normal?

Thanks
Ken

 

[Broken Crow]

Sounds like a 3/8" barb which is no big deal... are you absolutely certain it's 5/16"? Taprites sell with either 3/8" or 5/16", but shoving a 5/16" hose over a 3/8" barb is fine and personally, I've always tried to use slightly oversized barbs as an added measure of security.
In the meantime; Welcome back! Since you've been here a while, you're probably aware that we on here can make you paranoid about every minute detail so in that vein; When I got my own first CO2 gear, I went with vinyl gas line (5/16" on 5/16" swivel nuts > 3/8" regulator barb), but quickly became concerned about O2 ingress of my lines and swapped them out to EVABarrier and Duotights but after at least one faulty part and a few instances of my own incompetance, came to distrust Duotight and now I'm using EVABarrier swaged over barbs,,,and it is a strech but you can even swag 1/4"ID EVABarrier over a 3/8". I just did a couple the other day on my racking pump. A tight fit, within reason, makes for less chance of a leak.

 

[mac_1103]

and it is a strech

I see what you did there.

 

[kclebak]

Sounds like a 3/8" barb which is no big deal... are you absolutely certain it's 5/16"? Taprites sell with either 3/8" or 5/16", but shoving a 5/16" hose over a 3/8" barb is fine and personally, I've always tried to use slightly oversized barbs as an added measure of security.
In the meantime; Welcome back! Since you've been here a while, you're probably aware that we on here can make you paranoid about every minute detail so in that vein; When I got my own first CO2 gear, I went with vinyl gas line (5/16" on 5/16" swivel nuts > 3/8" regulator barb), but quickly became concerned about O2 ingress of my lines and swapped them out to EVABarrier and Duotights but after at least one faulty part and a few instances of my own incompetance, came to distrust Duotight and now I'm using EVABarrier swaged over barbs,,,and it is a strech but you can even swag 1/4"ID EVABarrier over a 3/8". I just did a couple the other day on my racking pump. A tight fit, within reason, makes for less chance of a leak.

Thank you for the reply. I did reach out to Keg Outlet where I purchased the regulator from and they confirmed 5/16.

Not happy to hear your comments about Duotight . I purchases a Komos V2 4-tap Kegerator that came with all Duotight/EVABarrier for the beer/liquid lines. I figured I would do the same for the gas lines, so when I purchased a Tap-Rite 4 Body secondary regulator and Tap-Rite primary regulator I went with 1/4 inch MFL thinking duotight. . What I failed to consider was the inlet on the secondary, which is the barb, and thus my original post. Is the 3mm ID x6.35mm OD the best size to use when connected to 5/16 barbs?

 

[Broken Crow]

Thank you for the reply. I did reach out to Keg Outlet where I purchased the regulator from and they confirmed 5/16.

Not happy to hear your comments about Duotight . I purchases a Komos V2 4-tap Kegerator that came with all Duotight/EVABarrier for the beer/liquid lines. I figured I would do the same for the gas lines, so when I purchased a Tap-Rite 4 Body secondary regulator and Tap-Rite primary regulator I went with 1/4 inch MFL thinking duotight. . What I failed to consider was the inlet on the secondary, which is the barb, and thus my original post. Is the 3mm ID x6.35mm OD the best size to use when connected to 5/16 barbs?

Don't let my bad experience with a few duotights sway you, 99% of Duotight users are perfectly happy with their perfectly functioning Duotight systems. (I can only be certain I had one bad part and the few other leaks I had are down to my own incompetence..I've got brain/spine/CNS damage that create a few extra hurdles for me)
I've got the 3mm ID line for my liquid, but I've got the 1/4"(6.35mm) ID for my CO2. The 1/4"ID can be swaged nicely over a 5/16" barb, but I doubt you'd get the 3mmID over it. Did you only get 3mm ID lines for everything? Do you have MFL's on the output of the secondary?
Here a visual: 3mm EVABarrier over a 1/4" barb:

You'll probably want either to get some larger line, even if just a short piece from the primary regulator to the secondary, or an MFL fitting to replace the barb. https://www.brewhardware.com/product_p/flarem14xmnpt14.htm