loose barrel

[JOHNNY WACKO]

so i am moving around some guns to make room for the new ar 458 i got coming from fordwannabe tomorrow and grab my ar in 762x39 by the brake and notice the barrel wiggled. that's the only upper i bought already built and the barrel nut is loose. the last time i fired it it was shooting fine and accurate as always. i think i am going to order a different hand guard with a steel nut and replace the aluminum nut with the gas tube through it while i have it apart.

don't want a mishap like sixgun had today with his uzi.

must be loose nut day today on here.

[pdentrem]

The steel barrel and the alloy barrel nut expand at different rates. If steel is 1, aluminum is around 5x steel, and this can cause an issue as you have noticed.
Pierre

[cas]

I always laugh at the "builders" online who swear the barrel nut MUST be torqued to "xyz" pounds.

For years I had an upper I got from someone with a free float tube on it, back when free float weren't all that common. The tube rocked left and right, but I didn't know much about them back then and just assumed that's what they did. I used that upper for years and it's still one of the most accurate AR's I've owned, never malfunctioned.

Years down the road I decided to take it apart, I pulled off the sight tower, pulled out the gas tube and the free flot tube/barrel nut spun right off almost by itself. The gas tube was the only thing holding it on, torqued right at 0 foot pounds.

[JOHNNY WACKO]

I had that happen 1 time before on a s/s barrel and it shot different every time i shot it till i tightened it up.
I like the nut that the tube don't go through.like the slim hand guards have this is a fat guard with the nyt that you use the wrench with the 3 pins to tighten it and the gas tube goes through it.
I have several like that on my pistols before the slim guards came. I think it was just not tight enough when built.
They say 45 to 90 pounds i just tighten them up till there tight

[Sixgun]

Hey Glen....was this your AR that shoots the 45 Auto? That was a neat gun...still have it..if it was yours? (Notice the case in the air with Silas shooting it) That is his name, isn't it..can't remember much these days........me

[cas]

I really enjoyed that day and recall it fondly, but the next day I found out my good friend/brother in law had passed that same day. You guys had all left by then. I got the new at the top of a hill, sitting in the Jeep with Frank H. That was also the last time I spoke to or saw him. Lots of mixed emotions all around that weekend.

Cyrus is the name you're thinking of. Spelled like that, but pronounced "Sirus".

Yep that was my rifle in the photo, but not the rifle I mentioned above. That 45 was an Olympic Arms upper on a CNC/Thompson Machine Grease Gun mag lower.
I sold it a few years ago in the height of Obama gun price mania. I had a lot of money invested in that gun, but I only shot it once or twice a year and that bugged me. I sold it with the intention of buying a nice over/under sporting clays gun, which would also only get used one or twice a year. And like almost every expensive gun I've sold the last few years to fund some other gun, instead the money went to the property tax. The real kick in the pants was literally day after I sold it, they passed the Safe Act, meaning I could never replace it.

Funny the Steyr Scout in the background. A rifle I meant to buy since shooting Uncowboy's at the 2000 Nor Easter. Sold another "spensive" rifle (another Safe act casualty) this summer and bought a scout, figured I'd shoot up my stockpile of 308 ammo. As it turn out, it doesn't like it. lol

[JOHNNY WACKO]

my loose barrel on my 762x39 ar15 ended up being a loose hand guard not the barrel nut.as i brought it down to my man cave to take it apart i found the allen screws were loose and the barrel was still as tight as the day i built it. was a releaf not to have to take it all apart to tighten it up.Was done in like 5 minutes and ready to go back in the shelf.

[marlinman93]

I'd use a drop of non hardening Loctite on the threads before assembly. The gas tube will keep it from turning, but how tight the barrel is depends on whether it lines up with the tube. Needs to be tightened or loosened until it allows the gas tube to line up.

[JOHNNY WACKO]

The main nut was fine just the 8 small allen screws that hold the guard on were loose.I did put a drop of l/t on them and tightened them up with my screw driver this time not a allen wrench. I will keep a watch on then from now on and mite go over my others to be sure there all good to go.Thats the only 1 i have with a site on the guard i like to keep my site/scope or what ever on the rail over the receiver just in case of that happening and my site be off. funny thing it shot fine last time out.how it got so loose setting in the rack is odd.
I have the jig that lines up the tube hole when you tighten up the barrel nut.That upper i bought already built from g/b .I have been using the slim guards were the tube don't go through the nut on my latest builds. they seem to be a bit easier to use and seem to hold better.IMO.but i could be wrong.