I need a new gas tube!

[jrabenius]

I am beginning to dislike S&W!
I broke two roll pin punches trying to get the gas tube pin out.
I ended up drilling the pin out, but damaged the gas tube.
Just ordered the Armalite gas tube referenced above, thanks for the link.
I'll let you know how it works when I get it installed.

I had the same issue this past weekend! I ended up shattering the roll pin, which fell out in pieces. The only thing I can think of is the hole in the gas block is too small for the roll pin diameter, effectively making the roll pin a "solid" pin (no spring tension).

Not sure what the gas blocks are made from (very hard - MIM'd or forgings maybe?), so as the drills used to make the roll pin hole wear, the holes get slightly smaller . . .

 

[Coryjs]

Geeez! I had the exact same experience with that roll pin. Ended up cutting my gas block to pieces to get the gas tube out. I OF COURSE damaged the gas tube while getting through the gas block. I had TWO punches that were the proper size and the block from brownells, so even with all the proper tools it just wasn't happening.

I'm was very disappointed in S&W's response to my call to customer service to buy a new gas tube. They said I would have to send my new rifle in, so they could install a new gas tube and gas block on it rather than sell me the gas tube so I could finish my free float install. If I send it in, I'll undoubtedly get back the same gas block and roll pin I had to cut up this time!

I just tried to order the Armalite AR-10 carbine gas tube. I really hope that works out. If not my plan is to tig weld my damaged gas tube to my new low profile gas block so all the ports are sealed and I get no leakage from the small spot were I nicked my current gas tube with the cutting wheel.

IF I get desirable function test, I'll be certain to post the parts I used. But again, seriously disappointed in S&W for not selling this gas tube.

 

[sgtsandman]

I guess I was lucky. The pin was a bit stiff coming out but I got it out. Of course, I didn't help myself by accidentally installing the tube upside down in the new gas block. No idea how I did it but I did and couldn't figure out why my rifle wouldn't cycle when I took it to shoot.

Took the block off. Ok, that was on right. Took the tube back out. Upside down. DOH!

 

[chino101]

Custom gas tube vendor

I'm wondering if there is a vendor out there that can custom make a gas tube for us if we get a group buy going. Anyone have a possible source?

 

[sgtsandman]

Black Hole Weaponry makes barrels for the M&P10, maybe them???

 

[Coryjs]

Black Hole Weaponry makes barrels for the M&P10, maybe them???

Wow, that's great news! Has anyone on here mounted one of these black hole weaponry barrels on their M&P 10? If someone could confirm fit up, I'd be pretty tempted to buy their 22" barrel. That is assuming I don't have to change the BCG etc, etc....

 

[sgtsandman]

There was a thread on barrel or shooting issues with the stock barrel and the BHW barrels were mentioned. I don't remember the specifics or if there was any follow up after a barrel swap. I'll look to see if I can find the thread and link it for you.

EDIT: There has been no follow up discussion on how the new barrel performs but here is the link to the thread for more information: http://smith-wessonforum.com/smith-...10-barrels.html?highlight=Black+Hole+Weaponry

 

[jrabenius]

Need a gas tube too!

I knocked the gas tube roll pin out, and couldn't get the tube out - it appears to be pressed in. Yes, I tried heating up the gas block, but it wouldn't budge.

SO, I took the gas tube/gas block to a local machine shop to have them remove the tube. I explained that I didn't care about losing the gas block, BUT THEY COULD NOT DAMAGE the gas tube in any way - I TOLD THEM THAT I COULD NOT REPLACE IT!

SO, you guessed it - they knicked the tube trying to cut the gas block off.

I called Smith & Wesson - TWICE, and spoke to two different techs. The first tech said they wouldn't sell me the tube - I had to send in my rifle for replacement. The second time I called, I asked for parts, and gave the guy the part number (430710000). He confirmed that that was the correct part number. He told me that he had 0 on hand, had no delivery date, and I should call them in 4 weeks and check again.

I HOPE SOMEONE FROM Smith & WESSON IS READING THIS!

I managed to get the tube out of the block. I measured the overall length (12.070 inches). The Armalite carbine length gas tube is advertised at 12 1/6 inches OAL (12.1667 inches).

I have ordered the armalite gas tube (SKU: 10007005). Price was $14.00 and shipping was $5. I will report back when I get it.

I am installing a JP Enterprises Low Profile Adjustable Gas block too. I'm using a UTG Pro Super Slim free float handguard (VERY NICE!).

Pics to follow.

 

[copemech]

someone else reported the Armalite tube worked fine. Cannot recall if they trimmed it a bit. As lonk as it does not hit the gas key and bottom out I would think it would be ok.

 

[jrabenius]

Armalite gas tube is an EXACT replacement!

Well, almost. It will definitely work as the original tube did.

I received the Armalite gas tube (they call it a carbine length, which is very confusing), and I measured them both with a set of calipers. The Armalite tube is .031 inches longer. For those of you out there, a sheet of copy paper is .005 thick, so 6 sheets of paper is roughly .030

I have spoken with several barrel companies lately, and they all agree that it is OK to be a little longer - as much as .100 longer, and it would work fine.

What you don't want is for the replacement gas tube to be a significant length SHORTER than the original gas tube. If it is shorter, the gas key will disengage from the gas key on the bolt carrier sooner, and could potentially cause short stroking.

 

[jrabenius]

Armalite gas tube is an EXACT replacement!

You do not need to trim the extra length from the Armalite gas tube - it will work just fine.

 

[copemech]

​

You do not need to trim the extra length from the Armalite gas tube - it will work just fine.

good on you!

 

[KentB]

You do not need to trim the extra length from the Armalite gas tube - it will work just fine.

This is true.
I replaced mine and the Armalite is an exact fit.
If you plan to replace your gas block, order a replacement block and the Armalite gas tube.

 

[sgtsandman]

Just out of curiosity what do you use to trim the tube? A pipe cutter like one for brake lines and then de-burr it?

 

[jrabenius]

gas tube trimming

You CANNOT just trim the gas tube. You would have to turn it on a lathe.

The end of the gas tube that fits into the gas block has a hole (port) where the gas enters from the gas block, The other smaller hole at this end is for the roll pin. The distance from the port hole to the roll pin hole is standard regardless of application (ar-15, ar-10, ar-308 etc). The positional tolerance between these two holes is most likely +/- .005, and would have to be perpendicular (90 degrees) to each other and the bend of the tube by no more than a few degrees. I can say this because the geometry of the gas block is universal.This end is also plugged to keep the gas from exiting from the tube from the wrong end.

It is not impossible, but it does take the proper equipment.

The other end is machined - turned down to a smaller diameter where it fits into the gas key on the bolt carrier. At the very end of the gas tube there is a small section that is a little larger in diameter which forms a piston like seal with the inside of the gas key. This end has to be turned down to form the "chamber" which drives the gas key. I'd be willing to bet if you didn't turn the end of the tube down, the tube would not seal into the gas key.

Merely cutting a gas tube down without turning the end down, and forming this gas seal will not work.

You would have to buy a rifle length .308 gas tube and re-machine the entire end where it fits into the gas key. The tube would have to be almost 2 inches longer than the finished length to allow for machining.

You would definitely need either a lathe or a mill (depending on which end you choose to machine).

I am the first to admit that I don't know sh!t. BUT I am a Mechanical Design Engineer with 18 years of experience, and I also own a lathe and a mill, and I have taken several machining courses. I have personally machined gas turbine parts for Garret (Allied Signal). I also reverse engineered 872 pieces of tooling required to service and overhaul gas turbine engines for Triumph Corp in Phoenix, and oversaw machining of those replacement tools.

If you wanted to build a gas tube for fun to see if it would work, fine. I don't think you would get hurt by doing so. Just be aware of the risks.

The positional and diameter tolerances would be +/- .002 AT MOST - some thing that cannot be done with a pipe cutter, hand drill or a bench vise.

Why bother anyway? For $15 you can buy the Armalite gas tube which is a direct replacement.

 

[bergermeister]

So How did the JP Adjustable Gas Block work for you?

I am a fan of SLR adjustables but they stopped manufacturing the railed block because they did not sell as well as their other stock. Need to get a railed block to retain the MP-10 configuration so JP will apparently be the go-to source now.

BTW; You stated: "I HOPE SOMEONE FROM Smith & WESSON IS READING THIS!" They aren't, they don't give a damn about the MP-10 clientele. S&W is too big to fail

 

[jrabenius]

JP adjustable gas block

I love the JP low profile adjustable gas block! It was easy to install, and even easier to adjust. I noticed a LARGE reduction in recoil after installing it on my M&P 10.

I am in the process of upgrading 2 of my AR-15's with the same block.

I have a Gemtec HVT 30 caliber suppressor, which fits the M&P 10, and both of my AR-15's - one is chambered in 5.56, and the other is in 300 Blackout. The adjustable gas block allows me to use the suppressor with subsonic rounds in these rifles.

 

[bergermeister]

Thanx-

Guess I'll give one a go!

 

[068]

I am a fan of SLR adjustables but they stopped manufacturing the railed block because they did not sell as well as their other stock. Need to get a railed block to retain the MP-10 configuration so JP will apparently be the go-to source now.

BTW; You stated: "I HOPE SOMEONE FROM Smith & WESSON IS READING THIS!" They aren't, they don't give a damn about the MP-10 clientele. S&W is too big to fail

There is a forum where a S&W rep will respond to you but I don't know if it is ok to post that link here. Some people are kind of funny about that stuff.

 

[masakari]

So I installed a new gas block on my M&P10, and now the tube rattles slightly in the block. This is most likely because I must have damaged it in the removal process. It was a bitch.
I'll need a new gas tube. I see the ArmaLite option (as it figures, I placed a different order with them and it shipped yesterday) but is there any progress on getting one from S&W yet? I'll be calling them on Monday. Sometimes I hate weekends.

Edit: I was able to convince S&W to send me a new gas tube for $36.