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Good Morning Gentlemen, pretty much a noob here, Would someone please be kind enough to explain to me what it means to have a unitized gas system and how is it done?Thank You.
 

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There are 2 ways to do it.1st is old skool. The front band is "glued and screwed" to the gas cylinder.
Later the glue and screw method was replaced by welding the front band to the gas cylinder.I'm sure someone will be along shortly to provide pics of each.
ETA,,to do correctly,there is a jig that is used to correctly line up the band and cylinder.
 

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There are two style's or methods. One is the Army version and that is too drill and tap, then screw it together using a thread locker and peening the screw heads. The down side is that the gas spindle valve is now always in the on position, if you have a good supply rifle grenades you can't use them.

The Marine style, was too weld at the 12 and 6 o'clock positions the welds are just a little bit larger than tack welds, this was fast and quickly done. The spindle was is still turnable too the off position for grenade use just incase you have any floating arround.

Both styles of unitizing use fixtures too center the front band and position the gas cylinder. What works best for you is a personal decision, both methods do the job. The down side too the Army version is if the screw head/heads break its a real pain too fix, if a weld fails with the Marine style it can still be dressed down and welded again.
 
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Another noob here. Will someone explain to me how this increases accuracy?
I have only owned a M14 for just about 2 years. As I understand it in a bolt action rifle there are few parts that can rattle and vibrate the barrel when a round is fired. Thats why they are inherently more accurate out of the box.

A M14 on the other hand has a bunch of moving and vibrating parts. Such as the op rod, magazine and the barrel band that's right behind the gas cylinder.

A unitized gas cylinder removes one source of vibration as the bullet travels down the barrel. This vibration can affect the accuracy and grouping as its a variable that cannot be predicted without the unitized cylinder.

Having said that the M14 is infinitely more fun than a bolt gun. And a challenge to shoot well. I have not gotten to that stage yet. But I'm having a hell of a good time though, LOL!!!!
 

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I have only owned a M14 for just about 2 years. As I understand it in a bolt action rifle there are few parts that can rattle and vibrate the barrel when a round is fired. Thats why they are inherently more accurate out of the box.

A M14 on the other hand has a bunch of moving and vibrating parts. Such as the op rod, magazine and the barrel band that's right behind the gas cylinder.

A unitized gas cylinder removes one source of vibration as the bullet travels down the barrel. This vibration can affect the accuracy and grouping as its a variable that cannot be predicted without the unitized cylinder.

Having said that the M14 is infinitely more fun that a bolt gun. And a challenge to shoot well. I have not gotten to that stage yet. But I'm having a hell of a good time though, LOL!!!!
Unitizing also helps put a small amount of pressure on the barrel so after its fired the barrel returns too its nearest at rest position.(ie. the muzzle is looking in the same direction betwen each fired round) Your never going too stop the rifles harmonics when you shoot it the best you can do is help midigate them, less stuff dancing arround helps.
 

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Unitizing a gas cylinder may or may not benefit a rifles accuracy. This modification is designed to work with glass bedding which accomplishes a couple of important things. First, glass bedding firmly secures the action in the stock to keep it from moving around. Proper bedding also positions the barrel slightly high above the stock ferrule. Unitizing secures the barrel band to the gas cylinder so it can't float around. Since the barrel is positioned high, the barrel band is pulled down by the stock ferrule. This tension stabilizes the barrel. In a bolt gun, the barrel can be free floated because nothing is attached to it that moves. In a gas gun the piston always moves which effects barrel harmonics. The object is to prevent as much movement as possible so all harmonics are as consistent as possible from shot to shot. Unitizing by itself can only be as effective as the relationship between the action and stock permits.
 

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Unitizing a gas cylinder may or may not benefit a rifles accuracy. This modification is designed to work with glass bedding which accomplishes a couple of important things. First, glass bedding firmly secures the action in the stock to keep it from moving around. Proper bedding also positions the barrel slightly high above the stock ferrule. Unitizing secures the barrel band to the gas cylinder so it can't float around. Since the barrel is positioned high, the barrel band is pulled down by the stock ferrule. This tension stabilizes the barrel. In a bolt gun, the barrel can be free floated because nothing is attached to it that moves. In a gas gun the piston always moves which effects barrel harmonics. The object is to prevent as much movement as possible so all harmonics are as consistent as possible from shot to shot. Unitizing by itself can only be as effective as the relationship between the action and stock permits.
So you don't unitize the gas cylinder if your action is not glass bedded? Do you glass bed a wood stock or only composite stocks?
 

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So you don't unitize the gas cylinder if your action is not glass bedded? Do you glass bed a wood stock or only composite stocks?
If you are not going to have the rifle glass bedded then you can simply shim the gas cylinder.

Unitized gas cylinders should only be used with a bedded action. Both wood or composite stocks can be glass bedded.
 

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Either type stock can be glass bedded, however I don't recommend bedding GI wood stocks that have been sanded too thin as many have. I don't mean to imply that there is no benefit to unitizing in a non-bedded rifle. It may or may not make a difference in accuracy depending on how the barreled action fits the stock.

Accurizing a M14 rifle is simply a matter of making all the parts recover from firing and recoil as consistently as possible. It helps to have a good barrel too, but that isn't the subject. The process is clearly spelled out and has been time tested for well over 50 years. Some of the new stock systems, JAE, SAGE, etc. work around glass bedding, but still apply the same principles to achieve accuracy.
 

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USMC welded, and you can also see a bit of bedding compound, just to back up what the knowledgeable ones have said.

I've shimmed, too with slight improvement in groups on a 16".

Against almost all advice here, I had the GC welded on my Bush without bedding the action and saw little benefit, but as someone has stated, it sure is great to say 'Yeah, I got the gas system unitized.' So, it goes without saying, bedding is my next step with it.
 

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So is it better to unitize the parts that came with your rifle, or to buy a pre-unitized system like LRB offers on their site? I know very qualified welders with their own TiG setup; one is my brother in law, another is a gunsmith who mainly builds AKs. I'm hesitant to have them do it, as there is no substitute for experience with a weapon platform.
 

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About Shimming

Shims were developed back when the Marines were using silver solder to do gas cylinder unitizing. Seems the silver solder wouldn't hold up well without a way to secure the barrel band against the barrel shoulder to prevent recoil forces from knocking it loose.

Shims can accomplish three things, but not usually three combined. The shims are used to tighten the gap between the gas cylinder and barrel shoulder as noted. This however does not guaranty that the barrel band will stay in place. Firing and recoil forces will often move the barrel band in spite of shimming. Shims can be used to align the barrel gas port with the gas cylinder port. Keep in mind that there is some leeway here as the GS port is larger than the barrel port. The third thing is that it can be used to adjust the position of the gas lock to get optimal tension on the whole assembly. This isn't as important as many seem to think it is. Having a space between the unitized barrel band and the barrel shoulder relieves binding between the gas cylinder and the barrel. It is not detrimental to accuracy. When this binding occurs, it can increase with barrel heating. Binding between these parts can actually bend the barrel. This has been confirmed with a barrel straightness gauge used to inspect several rifles sent to my shop that were shimmed to tight.

The point is that shims can provide some benefit on some rifles, but can't provide consistent benefits when used without unitizing which works fine without shimming.
 

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So is it better to unitize the parts that came with your rifle, or to buy a pre-unitized system like LRB offers on their site? I know very qualified welders with their own TiG setup; one is my brother in law, another is a gunsmith who mainly builds AKs. I'm hesitant to have them do it, as there is no substitute for experience with a weapon platform.
Zilla, even though your BIL might be an excellent Tig welder and the AK-47 Specilist might be an excellent GS, they are highly unlikely to have the fixture/jig necessary to hold the parts in alignment while the work is being performed. This would be especially true when using the welding method. Once that bead is started on one side of the GC/band, you can bet there will be warpage on the other side. Go with guys like LRB, as they got the proper gear to do the job. dozier
 

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So is it better to unitize the parts that came with your rifle, or to buy a pre-unitized system like LRB offers on their site? I know very qualified welders with their own TiG setup; one is my brother in law, another is a gunsmith who mainly builds AKs. I'm hesitant to have them do it, as there is no substitute for experience with a weapon platform.
The best unitized GC I have found is the one from Fulton Armory. It's done the Marine way with welds top and bottom. Tried out the Springer model and the two handguard tabs broke right off. Weird..
 

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I had hueygunner glue and screw mine and i can guarantee that if it ever comes apart ive got worse things to worry bout than a gc
 

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Thanks dozier and WalnutScout, you guys answered a question that had been rolling around the back of my brain for a minute. And dozier: that was my exact train of thought. Regardless that my BIL graduated top of his class, I'd rather get one from some M14 specialists like LRB or Fulton. (Even though that removes my reason to road trip to Vegas, where my family lives.)
 
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