I’ve decided I want to pair my global tactical barrel with my NSR handguard but the barrel nut will not fit over the barrel right at the barrel extension. It’s just slightly too large.
So can I sand this down? Do I need to ship it off to have it done? The area is pretty small in terms of the overall barrel length and it will be covered by the barrel nut itself. I’m sure Adco can do the most professional job but I’m wondering if a belt sander and a few minutes wouldn’t accomplish the same end. What do the experts think?
Barrel on right is one I’m talking about. Barrel nut fits one on left for comparison.
Yes. Standard colt and BCM barrel nuts fit just fine. The NSR is very tight inside diameter. I think it would be a very minor amount of material to remove to make the NSR fit.
i’d get it turned down in a lathe - i would not take it to a belt sander as there’s no way you’d be able to take off material evenly. my concern would be stringing due to asymmetrical expansion when the barrel heats up in that area. i might be completely off-base, but that’s why i wouldn’t do it.
edited to add - i might have initially misunderstood where the interference is. i thought you were referring to the widest part of the barrel, but now i’m thinking it’s the barrel extension shelf/ring right in front of the index pin. is the interference with the threads in the inside of the barrel nut? in that case, you can’t take material off the threads. so, maybe it’s okay to take some material off the outside diameter of the barrel extension ring with a belt sander as i can’t see how that would have a negative impact on accuracy.
I don’t think removing material from inside of the noveske NSR barrel nut is an option. I was I initially thinking of cutting the rainier barrel down and having it recon toured but decided to sell and replace as an easier/cheaper alternative to get what I’m wanting for that one.
The barrel nut slips all the way down the barrel to where the barrel bulges out just before the barrel extension. If you look closely you can see its wider than the rainier barrel next to it. I’ll get out the calipers in the morning to see how each measures. The rainier just barely fits but it does fit.
Basically, Bringing the barrel on the right down to the outside diameter of the barrel on the left just before the barrel extension is the goal.
The rainier measures 24.72 mm right before the barrel extension
The global tac measures 25.45 mm right before the barrel extension
We are only talking about 0.73 mm of difference here. I basically need to remove about 1 mm of the diameter on the global tac barrel for about 18 mm worth of length (about 0.7 inches)
I really hate to ship this thing off to Adco and pay lord knows what for such a small little thing, but I really want to use this barrel. I’m trying to find a gun smith with a lathe in my area but so far no luck.
Just find a reputable machine shop. Give them the barrel and nut, ask them to chuck it up in a lathe with a live center and you’ll be done in no time. The set up will take longer than the cutting (and neither will take long). Those guys are going to be just as anal as a gunsmith.
I see no reason they couldn’t. Just make sure they’re a good machine shop first, which i understand could be un-nerving at first. You will also want to stress absolute concentricity with the bore for anything they do. It may also help to know what steel the barrel is comprised of so they can go into the work knowing what kind of chip load they can get away with without stressing the material.
Edited to add: My comment here is in regards to a question of re-contouring a Rainier Arms barrel. The question has been removed by the OP so my response doesn’t fit the current subject of the thread.
Generally I would agree, but in this case turning a barrel down to the proper diameter really is not big deal, especially since it’s stainless. Boring the inside of the NSR nut is going to remove the finish and corrosion protection.
If the Global Tactical barrel is too large in diameter, contact them before turning it down. Without having shot the barrel, it’s not known if it has issues or not. Turn the barrel down and find out something is wrong, you’ll have trouble getting them to honor any warranty. I am not advising that you have to send it back, but contacting GT might open up more options. At the least, you will know exactly what to expect from GT if you still decide to turn the barrel.
Also, contact the maker of the NSR. They may have a solution for you. Maybe they can send you a nut that has the correct ID for your application.
At least if the NSR nut is honed, it’s cheap to replace in comparison to the barrel. Touching it up with cold blue will protect it from corrosion. If the finish of the NSR nut is parkerizing, it may just need a little smoothing out
Okay, so here is the full scoop. Someone on a local forum pointed me to a local gun smith. Went over there after a quick call with barrel in hand. They have the lathe to turn, cut and thread a barrel although they don’t go so far as to recontour since they can only do straight cuts on the lathe.
After studying the situation for a while, their take was that the barrel had a coating on the stainless and wasn’t just bead blasted. They said it looked like titanium nitride, but I don’t know if that’s true or not since Global Tactical seems to be gone now. This barrel appears to have a nice slick surface though, so maybe that’s what it is.
Anyway, the game plan we all decided on after talking to them was to use a jig and a sander to just slightly remove some of the surface. The measured diameter difference between barrel exterior and inside of the Noveske NSR barrel nut was somewhere between 0.6 and 0.7 mm. Hence, we are only talking about around 0.3 to 0.35 mm being removed around the circumference.
They had some sort of jig that allowed the barrel to roll/turn using the barrel extension surface to keep the material removed asymmetrically and concentric. I didn’t see it but based on how he described it and how the result looks, it appears to perfectly mimic the surface of the barrel extension.
The end result is that the finish material on the barrel is gone at this point and the Noveske NSR nut slips just perfectly over that area. It’s such a perfect fit that it actually makes contact with the barrel surface every so slightly. I’m talking tight enough that a sheet of paper wouldn’t pull out of the gap, but not so tight that you have any trouble turning the barrel nut smoothly by hand. You don’t feel any friction when applying the barrel nut.
On the surface, it looks the same as it did with the rainier barrel in it, but having around 5 oz less barrel weight with this profile seems to make all the difference in the world for how this setup feels and how it balances. I couldn’t be happier with how it turned out and can’t wait to get it to the range soon. Now I just need to get everything else finished up, tightened, staked and pinned.
Thanks. I didn’t have them do anything to the Rainier barrel. I just had them address the Global tac barrel so I could get it mounted with the Noveske NSR. Would probably send the Rainier to Adco if I end up getting it done.
It is my understanding that Global Tactical has gone out of business so I’m not counting on any kind of warranty with the barrel at this point. I’m honestly feeling pretty lucky that I even got the barrel since I ordered it back around Christmas and got it a few weeks later and now it looks like they are gone and the website is history.
Also, I should have clarified, but NSR is the Noveske NSR handguard. Just figured everyone knew what it was. If you saw the barrel nut in person you would understand why I’m saying it isn’t something you want to try to machine or mess with. Besides, it would probably be next to impossible to find a replacement one right now regardless of price.
