[becklr1]

What if someone stuck a device on the barrel to correct any flight issues with the BB right at the end of the barrel just before it exits to open air?

I think it may interfere too much, but I am going to make something. I have 2 ideas.

 

[sniperninja]

I saw something like this in a strafer, and all it did was make the groupings from 1ft to more like 15ft. Killed any accuracy and range it had.

 

[becklr1]

Yea that totally sounds plausible. I'll still try something. I like the idea of an idea and then actually trying it. I'll post pics in a bit, let me turn something out in aluminum.

 

[MGunner]

The Marushin M1 Garand has a "double hopup". I have no idea in hell what it does, but I think you should look into it..

 

[bobgengeskahn]

In some of the research I have been doing I saw a barrel that used rifling only in the last 3-4" to add a spin to stabilize the BB as it exited the barrel...

 

[becklr1]

Hmm, I think there is something to the idea. Not sure what. Have an idea or two but is is just off the cuff it is not well thought out.

Checked into the M1. I did find this which is worse than my horrible VSR was dong. Even missed 3 times. :'(

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I want to get to this at 50 feet. Not sure if it is possible. But to target shoot it is kind of a requirement. Airsoft guns are horrible target practice weapons. I want to address that.

Anyhow I'll post something up. May be a dead end but I suspect is enough time and thought was given to it something could work, it would have to be something different than a nub at the end though. Which incidentally is what I a trying ha ha. Not overly optimistic.

 

[inthetallgrass]

In some of the research I have been doing I saw a barrel that used rifling only in the last 3-4" to add a spin to stabilize the BB as it exited the barrel...

It's called the Falcon barrel.

 

[becklr1]

Hey great info o the barrel name thanks! Did it help any?

 

[bobgengeskahn]

Just did a quick google search and found this:
http://miairsoft.proboards.com/index.cgi?action=display&board=commerce&thread=38102&page=1

Looks like someone is doing something testing these Falcon Barrels. Unfortunately I have to run at the moment, so I don't have time to read it, so I figured I'd post it here so it doesn't get reclaimed by the internet never to be found again, and hopefully someone else here will find it useful too.

 

[inthetallgrass]

It does look good. Well, not for me as I have to keep my fps at 328.

 

[bobgengeskahn]

Oh, here is another link that is slightly more informative about the topic:
http://translate.google.com/translate?hl=en&ie=UTF8&u=http://www.interq.or.jp/hot/air-web/owali.html

 

[becklr1]

A backspin using an H nub then trying to change direction with a twist? I am skeptical. If anything neck it down like a choke. The twist is supposed to keep it from hitting the walls I gather. Unless I am missing something, the twist is also the wall. Perhaps drop the initial hop up all together.

Seems like a good backspin with a necked down choke to 5.95mm would be how I approach it.

 

[bobgengeskahn]

After reading some more, the Falcon barrel only has 8 straight grooves at the end of it for the last 4cm. The idea is that evenly expanding gas will expand around the BB creating a more stable cushion as the BB exits. Theoretically it makes sense....

 

[scar527]

Same Idea as the TK twist barrels, and those are proven concepts.Except that it looks to be specifically designed for higher FPS guns than the TK's.

 

[becklr1]

Really the TK twist barrels are proven? I have read they work good to they work horrible. I have yet to see anything definitive. I think proven is too strong a word.

So the Falcon barrel only has 8 straight grooves, they are not twisted then? That actually makes more sense to me if that is the case. Try and stabilize at the end. Using air pressure makes more sense that a mechanical means which I will try.

 

[inthetallgrass]

Really the TK twist barrels are proven? I have read they work good to they work horrible. I have yet to see anything definitive. I think proven is too strong a word.

So the Falcon barrel only has 8 straight grooves, they are not twisted then? That actually makes more sense to me if that is the case. Try and stabilize at the end. Using air pressure makes more sense that a mechanical means which I will try.

That's what I was thinking.

 

[blackfoot1]

I think old Sun Project rifles had a muzzle end hop up. It wasn't adjustable, it was just an O-ring set for a certain distance using a certain weight of BB. It was possible to swap the O-ring for a tighter/thicker one if you wanted to use different BBs, but I have no idea how effective it was...
I suppose it was like a VERY crude choke.

 

[becklr1]

I tried a design with a hop up that slipped on the end of a barrel. I did not try slotting the end although I wanted to I just could not machine it good enough. It would be easy to do if you only went in an inch. I tried to go in 4 inches it did not work so I tried another approach shows in the next section bellow. But i would look like this, one end slips over the barrel with a set screw and the other end has slots. The holes all around are just to reduce weight is all. For a springer you would need a big air cylinder I suspect.

Here is the one I did below. Looks similar to the one up top but it had two 5mm holes countersunk 1/2 inch end that intercepted the barrel at 10 and 2 o-clock. It was like a mickey mouse head, Then I stuck in an o ring with a tapered head screw that squeezed the o-ring into the bb barrel area depending on how hard you tightened the screws. Not a fan of dual adjustments, it was finicky.

That was a year ago. The kids used it for all sorts of things and I can not seem to find the 3 originals. Once I started working on a whole gun I lost some interest in testing this and never fully tested it. The wife and kids are all like "oh ya I remember seeing it" but no body know where.

But that basic design could be altered with just gas escape slots at the end like the version I rendered up top without any mechanical touching of the BB which is what I did.

Here is the barrel end of the mickey mouse version I did.

I suspect barrel tip designs are a push. May work may not not sure it address the core problem. It is like treating a symptom rather than the cause. Or so I suspect. Interesting to hear what I tried had been done before in some form with barrel tip interference.

This means they were trying to fix the problem the same way I was so "they" are aware of the "problem".

 

[inthetallgrass]

I tried a design with a hop up that slipped on the end of a barrel. I did not try slotting the end although I wanted to I just could not machine it good enough. It would be easy to do if you only went in an inch. I tried to go in 4 inches. It would look like this, one slips over the barrel with a set screw and the other end has slots. The holes all around are just to reduce weight is all. For a springer you would need a big air cylinder I suspect.

Here is the one I did below. It had two 5mm holes countersunk 1/2 inch end that intercepted the barrel at 10 and 2 o-clock. It was like a mickey mouse head, Then I stuck in an o ring with a tapered head screw that squeezed the o-ring into the bb barrel area depending on how hard you tightened the screws. Not a fan of dual adjustments, it was finicky.

That was a year ago. The kids used it for all sorts of things and I can not seem to find the 3 originals. Once I started working on a whole gun I lost some interest in testing this and never fully tested it. wife and kids are all like "oh ya I remember seeing it" but no body know where.

But that basic design could be altered with just gas escape slots at the end like the CAD mock up without any mechanical touching of the BB which is what I did.

Here is the barrel end if the mickey mouse version I did.

A problem I see is that lower power guns would have their FPS significantly reduced and the BB would for sure bounce around the barrel after meeting the O-ring.

 

[becklr1]

Ya I think that is what would happen. Never tested completely. Know what was weird the FPS seemed to go up. I think due to being held up and pressure building and being shot out, never looked into it too hard, but to the eye it was faster.


That aside, the one above in the CAD is just slots like the Falcon barrel. Pretty easy to make a slip on that does the same thing.