Odd gas tube dimension

[Hoot]

Forgive me if I don't know this dimension precisely. I got a barrel I have been waiting for and when I went to assemble the upper, the mid-length gas tube I bought from Midway appears to be too long from the key end to the centerline of the port hole in it. I measured it and it is 11.25" to the centerline of the hole. The barrel wants it to be no more than 11". Anyone have a mid-length tube that they can measure to the centerline of the port hole, before I contact Midway. Not sure if the problem is with the barrel manufacturer or the tube.The only other tubes I have are rifle length.
TIA

Hoot

[commander faschisto]

You should know better than to throw me a hanging curve ball in that post, Hoot...I'll restrain my normal urge to say something stupid about tube length...

Back on topic, the mid-length tube is supposed to be 2" longer than the carbine-length. I've seen it listed as 11 3/4" OAL, or 29.9cm, if that helps...?

Apparently, the gas port should be at 9.8" also, for mid-length.

[Hoot]

You should know better than to throw me a hanging curve ball in that post, Hoot...I'll restrain my normal urge to say something stupid about tube length...

Back on topic, the mid-length tube is supposed to be 2" longer than the carbine-length. I've seen it listed as 11 3/4" OAL, or 29.9cm, if that helps...?

Apparently, the gas port should be at 9.8" also, for mid-length.

The plot thickens. The entire tube is 11-3/4", but that 9.8" (actually 9.795") I believe is the spec from the bolt face to the barrel port centerline location. That got me thinking. I measured the distance from my bolt face to my barrel's port and it looks to be .25" short. It's my bed time and I'll double check everything tomorrow.

If that is the case, it will be heartbreaking as the barrel is a one of a kind (my specifications) wildcat. I may end up trying to shorten the gas tube, but putting that "tapered nose" on it where it goes into the gas key will be a real challenge. I'd rather not send the barrel back as the fellow who made it under-quoted me on the price and is already on the "sh*t end of the stick" on the project, not to mention it was his last blank in that caliber. The timing on the caliber is flexible enough that .25 inches will not matter.

Now to try to sleep...

Thanks,

Hoot

[tridentarmory]

There can i e a surprising amount of variation there and everything still work just honky dory.. cut off a smidge...
somply close the bolt and move the gas block back gently till u find resistance. Then measure to the gas blk shoulder... cut that amount off your tube.clean the edges with a file. Chamfer a smidge witha. Case prep tool, and go to town.
Just be sure while pushing on the gas block you can feel the tube enter the carrier key... then a smidge of resistance is all you need... i actually cut mine which is a funky custom length setup about an eighth shorter than the resistance point and couldnt be happier.

[Hoot]

Well, I tried three different BCAs and the distance from all three's bolt faces is 9.50 to the port centerline, not the specified 9.795.

I'm a recent (last 3 years of 26) user of black rifles and always assumed the wider diameter and tapered nose on the end of the tubes was necessary to seal to the internal taper of the key. If that's just for show, I won't worry about it and just cut it off and deburr the stub.

Hoot

[Siringo]

What about cutting the tube midway and removing .30 inches from it and then sleeveing it, silver solder the sleeve onto the tube??

[tridentarmory]

Cut it off hoot. Taper it, make it pretty... if it doesnt make you happy, ill send you one


Seriously, chamfer it make sure its straight in the channel and run it...
Ill cover you one if its a no go.

[tridentarmory]

What about cutting the tube midway and removing .30 inches from it and then sleeveing it, silver solder the sleeve onto the tube??

Ummmm..... no... waaaaayyy to much wasted time/effort for a 15 dollar gas tube

[tridentarmory]

Call me if u have issues, ill be in the shop for a.couple hours tomorrow trying to get wicked hunters 450 ammo out to him and another dozen boxes or so....

Im buried...

[Hoot]

The fellow who made me the barrel said if it were him, he'd take a rifle length tube, shorten it as needed at the block end and re-do it there as opposed to trying to recreate that swage tapered end. Duh, why didn't I think of that? He offered to do it for me since he didn't re-zero his DRO when he drilled the port, but I said I would have a go at it first and take a rain check. I love a challenge like this and I do have an extra rifle length tube. The things you do for love.

Hoot