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Bloop Tube

As above, for position shooting with aperture sights a bloop tube allows the foresight to be placed beyond the muzzle, without the inconvenience of extra barrel steel. Yes a long (12in) aluminium tube adds weight, say 10oz+/-, but a whole lot less than an extra 12in of barrel.

What does this actually do? In theory it reduces parallax error, although one British Champion found no difference over 4in when SCAT testing. The longer sight radius may be more comfortable on terms of focal length, and will make rearsight adjustment finer.
 
There are those that feel like it helps and use them as a tuning device. IME, they can very well affect tune but are nothing more than a HUGE swing at tune when used for that purpose. To me, signifying that maybe they were moving the tuner too much at a time and chasing their tail when trying to tune. That weight may randomly bring them into or very near tune. Again, randomly being the key word. That said, if it works, do it.
 
It lowers my point of impact by about a inch. This was shot with and without the tube at 100 yards and no adjustments to the tuner except removal the tube
 

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Good Discussion...

Aside from the increase sight radius, potential tuning benefits, and certainly the cool sound one might also consider this something that helps modulate the transition from bore to atmosphere at the critical junction of the muzzle. At least for rimfire.

Maybe creates a transition zone for the bullet for some "quiet time" to help stabilize and maybe protect against crosswind.

Here's a carbon fiber vented bloop tube we put on a CZ457 with the Lothar Walther barrel. Still studying groups and performance but things look promising.
 

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Good Discussion...

Aside from the increase sight radius, potential tuning benefits, and certainly the cool sound one might also consider this something that helps modulate the transition from bore to atmosphere at the critical junction of the muzzle. At least for rimfire.

Maybe creates a transition zone for the bullet for some "quiet time" to help stabilize and maybe protect against crosswind.

Here's a carbon fiber vented bloop tube we put on a CZ457 with the Lothar Walther barrel. Still studying groups and performance but things look promising.
I used to think this too. However, after using a tube for a season in ARA in the Texas wind I don't think it helps anything. It was just wishful thinking on my part
 
Good Discussion...

Aside from the increase sight radius, potential tuning benefits, and certainly the cool sound one might also consider this something that helps modulate the transition from bore to atmosphere at the critical junction of the muzzle. At least for rimfire.

Maybe creates a transition zone for the bullet for some "quiet time" to help stabilize and maybe protect against crosswind.

Here's a carbon fiber vented bloop tube we put on a CZ457 with the Lothar Walther barrel. Still studying groups and performance but things look promising.

On another forum, I threw Bernoulis principle out there and speculated on how vented tubes might be affecting turbulence on the heel of the bullet but the more I play with them the more I have doubts it has any meaningful effect on accuracy
 
On another forum, I threw Bernoulis principle out there and speculated on how vented tubes might be affecting turbulence on the heel of the bullet but the more I play with them the more I have doubts it has any meaningful effect on accuracy
Years ago, there was a guy (Don B.) who made bloops. he made one with an insert that vented the gases outward to ports of the tube. it was his first design, and I did some testing with it. I also blocked the ports on some of the tests and got some really surprising results. on one rifle it made the shots go about 10-feet to the right. even Don couldn't understand why. every other rifle it worked fine. using this bloop I got decent results. nothing where I would say would be breakthrough.
Later with his carbon fiber bloop results were better as weight was reduced to under 12oz. total if I remember.
here is what it looked like.
1703344426675.jpeg
In fairness I didn't do a lot of testing with it as at the time Don sent me this to test I already transitioned to lite weight tuners of under 5-oz. he did make a carbon fiber body tuner which I was excited about as with a bloop the whole setup would be under 8-oz. I never got to test one of those as Don seemed to have dropped out of the shooting scene. here is what it looked like with my notes on getting a secondary adjustment ring put on one.
1703344669810.jpeg
Lee
 
I experimented a bit with mine and a chrono and found that blocking the ports affected the FPS. I have a FX subsonic chrono in the mail which should be here by the end of next week and I will do a more extensive test then. I bought the little chrono to test temperature vs velocity on rimfire but playing with the tube will be interesting also
 
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Good Discussion...

Maybe creates a transition zone for the bullet for some "quiet time" to help stabilize and maybe protect against crosswind.
When I started shooting in the '90s a "still aur" effect was sometimes touted as a benefit of tubes. However others noted that the propellant gas is travelling rather faster than the bullet and is contained with the tube so the inside is very much not still.

Israeli Olympian Guy Starik discussed tube ID in relation to gas turbulence on the TargetTalk forum a few years ago. If I remember correctly he found the minimum ID was 13mm.
 
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I've made a few and a friend has tested them on his Tikka over the last few weeks. He reported to me that the different weights/lengths did affect group sizes, ie acted as a tuner of sorts. Ymmv :)
 

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