BA Sniper Rifles: Spacers vs No Spacers?

[krap101]

So... I've been reading up on sniper rifles (RS), and free floating barrels, and am wondering if this applies to airsoft i.e. I have a fully upgraded vsr-10 (everything except the rail, hopup chamber, bolt handle, and and screws), and am wondering whether barrel spacers make it more accurate? Intuition tells me that since airsoft is much different than RS (no rifling, no super high pressures, thinner barrel walls etc), barrel spacers would be better, but I was just curious...

[m102404]

RS and AS are two very different systems. In RS it's a common thought that fully supporting the receiver and perhaps an inch or so of the barrel in front of the recoil lug allows the barrel harmonics to not be influenced by any external pressures from the stock. The barrel is going to vibrate like a tuning fork with each shot...and allowing it to be as free vibrating as possible maximizes the chances that it'll be in the same spot each time the bullet exits the barrel.

In AS...the inner, if not held in place by spacers, is only held by the hopup unit at the very end-tip of the barrel (essentially). It is not sufficient support to hold the inner barrel centered in the outer barrel. Essentially, it'll flop around randomly. And since AS BBs, essentially, don't contact the inner barrel...there's no real harmonics to speak of. Sure there's vibration from the spring and piston impact...but no in the same way as the internal ballistics of a RS system.

So...will spacers make an AS BA more accurate? Yes.

[CDN_Stalker]

Agreed. Look at how crappy some Armalites can be for accuracy, compared to something like an MP5, the Armalite is only held in place by the hop up really, where an MP5 has the hop up, the steel bracket to hold the inner barrel to the cocking tube, and the front sight at the muzzle.

He's a good example: KSC Glocks have a free floating inner barrel with a thin O-ring around the barrel, and are only held in place by the hop up unit. When the slide is in battery, you can stick a pen tip in the muzzle and see how much the inner barrel moves around, typically it can be a couple millimeters in every direction. Add a thicker O-ring, or wrap it up with electrocution tape and juggle tightness with slide disengaging ability. Doing the tape mod to reduce the moving around will give about a 75% increase in accuracy, vs. the rough 25% increase by just adding a tightbore. Ball park numbers, but I've done both and found a massive increase in accuracy and consistancy with the O-ring tape mod, but a minor increase with a tightbore.

[krap101]

Thanks for the reply guys. I was asking this in terms of b/a sniper rifles (vsr-10 specifically), since the hopup is secured to the outer barrel pretty well, rather than being slid in somewhere... somehow... I'll go pick up some barrel spacers when they get back in stock (I have laylax bull and normal spacers, but they don't fit the pdi outer barrel).

[Kos-Mos]

I wanted to try something with my next L96...

I want to wrap the barrel with some thin aluminum foil and then fill the whole outerbarrel with expanding foam... it should hold the barrel tight enough to make it extremely consistent, yet removable since the aluminum foil won't stick to the inner...

Other than this extreme mod, I used to take some nylon tape (white packing tape with fibers in it) and wrap it around the inner to make some barrel spacers... takes a lot but it's cheaper than any barrel spacers out there.

[krap101]

I know noobie made some silicone spacers for the vsr-10, which seemed to work well, (I could probably do the same thing pretty easily), but I don't think that the expanding foam would work well, unless it's expanded ahead of time (assuming you're talking about great stuff). I might be wrong, but FME, it doesn't expand evenly, and you'll be putting pressure on "random" parts of your inner barrel. If you use the two part expanding foam, you'll have better luck, but it still may be a problem.

Noobie is my hero

http://www.airsoftforum.com/board/No...c-t134507.html

http://www.youtube.com/user/T00BIE#p/u/9/_8eZfiecBVM

[Kokanee]

Electrical tape around the inner barrel works just fine as a spacer.

[mr_nuts31]

I find teflon plumber's tape to work quite well over electrical tape

[Habs19]

As far as I know, masking tape works well also, as it leaves no residue on the barrel and it's pretty cheap.

[chaz]

[ThunderCactus]

one barrel spacer at the end of the inner barrel. done.
The hop chamber holds one end of the barrel, spacer supports the other end.
The hop chamber isn't sturdy enough to hold the barrel in place to any sort of repeatability on it's own.
But don't be an idiot and fill the outer barrel with spacers either, that will contort the inner barrel to the outer barrel.
Just support it at two places and that's perfect