Efficiency mod?

[hill160881]

So i was tinkering around with putting an oring somewhere on the powertube to reduce bolt wear and maybe seal up a bit better when the bolt is forward. I did this by clamping the brass piece in a drill and held a fine tooth reciprocating saw blade to it as it turned.

Normally i get around 1600 to 1700 rounds on a 88 ci 4500psi fill. After installing the moded brass power tube thingy i got 1500 on a 3500 psi fill with the same tank? It also had a big difference in sound. A side by side comparison left no doubt that it was quieter. I only need to do a chrono test to confirm my results.

Any thoughts? Has this been tried before? Could the rate of fire affect the efficiency, meaning will shooting in full auto at 20+ bps cause it to get better efficiency.?

http://i971.photobucket.com/albums/ae195/hill160881/Temp/Projects/100_0957.jpg

[BigEvil]

Nice.

:ninja:

[hill160881]

This is after 5000 rounds. Notice how flat the o-ring is. I think a urethane o-ring would hold up better though.

[Smoothice]

Interesting. Very interesting. Thats pretty cool.

[Sniper Steve]

I am impressed, I want to try this myself.

[M98Punk]

How many balls have you put through this?!?!?

This sounds like a worthy mod to do with my micropistol..... ya know after I finally get the spring feed fixed :-P

[Old School 626]

Thinking about this section of the marker and how things work I think you'd be better off sealing the valve to the body where there less a probability of tolerance issues.

What you are doing is sealing off any wasted gas escaping back down the sides of the power tube. You could do the same thing with an over sized OD on the bumper such that the bumper seals against the side of the body. It'd likely be marginally less efficient if you believe that volume reduces efficiency but probably more reliable in the long run.

Good on ya for trying something new!

[RogueFactor]

Any thoughts? Has this been tried before?

It has, but not publicized. This was something I tinkered with back around late ~2006. I did it on both a L10 and L7 tip, here is a pic:

http://www.pblegion.com/attachment.php?attachmentid=331&stc=1&d=1297724032

[Spider-TW]

Thinking about this section of the marker and how things work I think you'd be better off sealing the valve to the body where there less a probability of tolerance issues.

What you are doing is sealing off any wasted gas escaping back down the sides of the power tube. You could do the same thing with an over sized OD on the bumper such that the bumper seals against the side of the body. It'd likely be marginally less efficient if you believe that volume reduces efficiency but probably more reliable in the long run.

Good on ya for trying something new!

You would still loose the air through the sear slot.

Bolt leaks are indeed annoying.

[hill160881]

Thanks everyone and good ideas. I will try a chrono test this next weekend.

I warn anyone trying this mod to GO SLOW or go to far.

[Spider-TW]

It has, but not publicized. This was something I tinkered with back around late ~2006. I did it on both a L10 and L7 tip, here is a pic:

http://www.pblegion.com/attachment.php?attachmentid=331&stc=1&d=1297724032
Any opinion?

[hill160881]

It has, but not publicized. This was something I tinkered with back around late ~2006. I did it on both a L10 and L7 tip,

I totally guessed on the location of the oring. Did you get any test data?

This valve can be viewed ripping with this mod at 25 bps. Its the valve in the minigun mag.

[RogueFactor]

I totally guessed on the location of the oring. Did you get any test data?
I did, which is why the idea was shelved. The benefits were negligible. It did however lead me in new directions with my testing and prototyping, which was really the benefit of it all.



Any opinion?
Its an interesting modification for the tinkering type, but by itself it was not something I found worth pursuing.

[hill160881]

So could the sustained high rate of fire be what is giving me better efficiency?

And what about putting the oring inside the bolt like a sail oring? Then it would maintain contact with the power tube the entire time.

[pinkanese]

Did you ever try putting a seal at the front of the breech or perhaps adding a ring to the bolt? Seems like doing this mod and sealing the front end of the bolt could have a larger impact.

[hill160881]

This is where i was thinking of turning an oring grove. Where the point of the pick is, Then it would stay in contact with the power tube the entire time
http://i971.photobucket.com/albums/ae195/hill160881/Temp/Projects/100_0961.jpg

[RogueFactor]

Did you ever try putting a seal at the front of the breech or perhaps adding a ring to the bolt? Seems like doing this mod and sealing the front end of the bolt could have a larger impact.

That was the very first thing tried(pic below). It was tried on a L10 bolt. This is what lead me to eventually modify the powertube tips, hoping the combination would have a noticeable effect.

It was really an idea that Smart Parts came up with, with their 'Seal Forward Technology' or SFT. This also had negligible effects, both alone and later combined with the modified powertube tips.

http://www.pblegion.com/attachment.php?attachmentid=332&stc=1&d=1297728181

[Tao]

Interesting idea. Ive noticed air coming through the sear space when I had leaks down the barrel.

I am interested in what TK has to say ;)

[TwilightG]

It has, but not publicized. This was something I tinkered with back around late ~2006. I did it on both a L10 and L7 tip, here is a pic:

why not publicize it? :confused:
I can understand if you were looking to sell a product, that makes perfect sense.
But since you ended up shelving the idea, why not share your findings w/ the Automag community?

Even if the results are negligible, would you mind posting the data you have? This could be more beneficial for pump-mag owners who are trying to get as much efficiency as possible.

[68calsportz]

I would love to see what comes out of this mod. I play alot of outlaw ball and i love my mags. But, air hogs they are. Is any one gonna do some intensive testing or what?

[cockerpunk]

That was the very first thing tried(pic below). It was tried on a L10 bolt. This is what lead me to eventually modify the powertube tips, hoping the combination would have a noticeable effect.

It was really an idea that Smart Parts came up with, with their 'Seal Forward Technology' or SFT. This also had negligible effects, both alone and later combined with the modified powertube tips.

http://www.pblegion.com/attachment.php?attachmentid=332&stc=1&d=1297728181

the level 10 bolts already had about a .005 swell around the nose in an attempt to seal the breach a bit better.

[Spider-TW]

So could the sustained high rate of fire be what is giving me better efficiency?

And what about putting the oring inside the bolt like a sail oring? Then it would maintain contact with the power tube the entire time.

It's possible. That rate suggests you have a high input pressure though...

http://www.airgundesignsusa.com/rtchrono.shtml

It depends on how you counted your other tank for comparison.

[RogueFactor]

why not publicize it? :confused:
I can understand if you were looking to sell a product, that makes perfect sense.
But since you ended up shelving the idea, why not share your findings w/ the Automag community?
For many reasons, but foremost because everything I prototype and test is for the purpose of creating new products. The idea was shelved(not abandoned) to be revisited.


Is any one gonna do some intensive testing or what?
Its not a hard modification to do, nothing really to stop anyone from doing it themselves.

[hill160881]

It's possible. That rate suggests you have a high input pressure though...

http://www.airgundesignsusa.com/rtchrono.shtml

It depends on how you counted your other tank for comparison.

No high pressure, just the normal 850 psi input.

[Dirge]

I would love to see what comes out of this mod. I play alot of outlaw ball and i love my mags. But, air hogs they are. Is any one gonna do some intensive testing or what?

Second that. I would like to see if this leads anywhere (more shots are always welcome :) )

[Smoothice]

Way to go Hill for trying new things.

I wonder how this an Loguzzzzzz's valve devolumizing mod (wow. Try and say that 3 times fast) would work with 12 gram use. I know I got quit a jump in shots per 12 gram with my "testing" of the devolumized valve.

[hill160881]

devolumised, with the oring on the brass thingy, with an oring on the front of the bolt mite all add up to a hell of a gain. It will be a while but i will do all the testing i can. I just need one of those Level 10 bolts rogue has with the oring on the front.

[Sandman]

De-volumizing (is that a word?) the valve does create more efficiency but raises the operating pressure of the gun. It's already been done and even sold. We called it the HyperMag. Some of you may remember that. It was only on a classic valve. Jeff Schrieber (past airgun tech) used to make the modification to other guns.
Here is a pic of the valve.
<a href="http://www.foxpaintball.com/uploadedimages/hypermag.jpg"><img src="http://www.foxpaintball.com/uploadedimages/hypermag.jpg" width="600" height="450"></img></a>


We did it for two reasons. Efficiency and trigger speed. Mags love high pressure. The higher they run the faster things move and the tighter the guns felt.

The power tube tip o-ring was done years ago too. The problem is, I don't remember what the conclusion over it was. Obviously it was never put on a production gun, but again I can't remember why. Tom might remember. I have a note to him seeing if he recalls what the findings were.
Sandman

[hill160881]

I would be interested to see why they did not put a version with all these modifications into production. Maybe it all adds up to a small gain but not worth the extra effort in production.

[Sandman]

Tom's response was simple
"because the o-ring's didn't last and rolled out of the groove. tk"

Can't hurt to do more testing.

[hill160881]

I would still like to test all three mods together and see what the efficiency difference is. I may have to replace orings often, but to be able to shoot 1500 rounds on a 68/45 would be awsome.

I wonder if they ever tried to put the oring on the inside of the bolt like i pointed out in an earlier post?
It would maintain a seal the whole time the bolt is in motion not just when the bolt is all the way forward. Not sure it matters because im not sure where, in the bolts forward movement, the shoot chamber vents.

[Rudz]

looks good, nice work Hill

I think for the pump mag guys running 12 grams, coupled with Loguzzzzz's devolumizing mod and this o ring mod, Im sure we can squeeze a few more shots out of the set up

[Spider-TW]

looks good, nice work Hill

I think for the pump mag guys running 12 grams, coupled with Loguzzzzz's devolumizing mod and this o ring mod, Im sure we can squeeze a few more shots out of the set up
Well, you can get CO2 out of a turnip with enough heat. :p

[Sandman]

Friction, wear and o-ring roll out might be an issue with higher rates of fire, but doubtful that it would be an issue for pump users shooting 12 grams. Not unless they can pump shoot 25bps.
I'd be curious to see efficiency results on a 12 gram.

Hill, you need to grab a 4500 psi life pack from your local fire station and blast away!

[Smoothice]

Hill, you need to grab a 4500 psi life pack from your local fire station and blast away!

http://www.automags.org/forums/showthread.php?t=255318

http://i971.photobucket.com/albums/ae195/hill160881/100_0890.jpg

[hill160881]

^^^^^
Thanks

Got two of them, and am making the adapter for a regular tank reg this weekend.




That, the video below, is a video of the power-tube oring mod in action.

[Rudz]

^^^^^
Thanks

Got two of them, and am making the adapter for a regular tank reg this weekend.


pffft and these people think hes joking


http://www.youtube.com/watch?v=8Usv-rgM8Hk :shooting: :shooting:

[Spider-TW]

pffft and these people think hes joking


http://www.youtube.com/watch?v=8Usv-rgM8Hk :shooting: :shooting:

That does look like fun. That would be great on a paintball 'city' made of metal containers.