Building a better balanced valve

[rsterne]

I would stick to the conventional (stock) preloaded hammer spring for now, until you get a baseline.... Then you will be able to assess how the ART/Sikes valve responds to an SSG or TSS after that.... One change at a time, Travis.... *grin*....

You may find out that the new valve is getting some of it's efficiency by clamping hard as it closes, and preventing hammer bounce all by itself.... That little metering rod in the Cothran stem is helping his valve do that.... The pressure in the balance chamber is high by the time the valve shuts, and takes a while to bleed down past the rod.... which acts like a "leaky check valve".... and if the hammer hits it again during that time period, it can't open the valve because there is pressure on the entire poppet area.... At least I think that is what is happening.... and your valve may be acting in a similar fashion because of the tiny bypass ports....

Bob

[oldpro]

 Ok will do.

[oldpro]

Biggest combat in closing valve fast enough is time/duration, which can be reduced by less lift since lift = duration, which is reduced by higher flow.

What do you mean by Higher Flow?

[rsterne]

I think he means that you can make up for shorter dwell and less lift by making larger ports for higher flow.... which is true up until the ports equal the bore.... You're already there, or beyond, for a .25 cal though, right?....

Bob

[oldpro]

 I thought he was talking flow drag on poppet stem....Im not sure so thats why Im asking. Im maxed out on port sizes. And to be honest this gun wasnt designed to be run unregulated so It might be a struggle but I am up to the challenge.

[oldpro]

 Im going to call my buddy SilentMatt and see If he can make me up a few prototypes Im really stretched for time and will need help from a few friends to get data.

[PeterL]

Without giving too much away, what are the port sizes Travis?

Peter

[mann]

Would like one of these for my marauder .25  which is unregulated . Are you going to be selling a transfer port with the valve  .

[oldpro]

  One of the problems is the hammer weighs 70g and is way to heavy for this new valve so right now Im making a 37g hammer. After that Ill need to message a few things to make this gun work efficiently unregulated. Give me a bit ill get this to happen.  I just noticed my barrel port this whole time is .185 so its not taking advantage of the large .250 TP so I will have to make a necked down TP as well.

[oldpro]

Without giving too much away, what are the port sizes Travis?

Peter

Valve throat .280 and TP .250 barrel port .185

[PeterL]

Without giving too much away, what are the port sizes Travis?

Peter

Valve throat .280 and TP .250 barrel port .185

Not bad with the restriction of the barrel and TP. That's real good power. Not bad at all. Make her breathe.

Peter

[oldpro]

Without giving too much away, what are the port sizes Travis?

Peter

Valve throat .280 and TP .250 barrel port .185

Not bad with the restriction of the barrel and TP. That's real good power. Not bad at all. Make her breathe.

Peter

Yes Sir especially from a 15" barrel

[oldpro]

Pulling gun apart today and sending off drawings and valve to Matt but I did have time to run a string with light hammer and Regulator

Created: 08/04/17 11:39 AM
Description: Warp .25
Notes 1: ART/Sikes 15" barrel
Notes 2: 2900/2000 13ci tank
Distance to Chrono(FT): 1.00
Ballistic Coefficient: 1.000
Bullet Weight(gr): 25.40
Temp: 79 °F
BP: 30.04 inHg
Altitude: 0.00
#          FPS   FT-LBS       PF
27    897      45.39    22.78   
26    899      45.59    22.83   
25    900      45.69    22.86   
24    905      46.20    22.99   
23    898      45.49    22.81   
22    899      45.59    22.83   
21    901      45.79    22.89   
20    908      46.51    23.06   
19    900      45.69    22.86   
18    901      45.79    22.89   
17    900      45.69    22.86   
16    905      46.20    22.99   
15    898      45.49    22.81   
14    905      46.20    22.99   
13    901      45.79    22.89   
12    904      46.10    22.96   
11    904      46.10    22.96   
10    904      46.10    22.96   
9     905      46.20    22.99   
8     902      45.89    22.91   
7     908      46.51    23.06   
6     900      45.69    22.86   
5     908      46.51    23.06   
4     907      46.40    23.04   
3     905      46.20    22.99   
2     903      46.00    22.94   
1     899      45.59    22.83   
Average: 902.4 FPS
SD: 3.3 FPS
Min: 897 FPS
Max: 908 FPS
Spread: 11 FPS
Shot/sec: 0.0
True MV: 903 FPS
Group Size (in): 0.00

[kkarmical]

That's impressive Travis,  very impressive as a matter of fact!  Great work.

[SilentMatt]

Very impressive indeed! Can't wait to get started on the prototypes.

[triggertreat]

Yes indeed it is impressive!  Travis you are getting in a lot of trigger time working out the details on this new jewel. I calculate the efficiency to be very impressive too at 1.53 FPE cu/in.

[oldpro]

It was a 13ci ninja tank I had to go back and fix post I mistakenly put 16ci / Im still not using and anti bounce devices during this test.

[ezman604]

Don't panic, I just moved it to the Engineering-Research & Development Gate where it should be.

[triggertreat]

It was a 13ci ninja tank I had to go back and fix post I mistakenly put 16ci / Im still not using and anti bounce devices during this test.

Yes, I assumed that from previous post and based my efficiency calculation on 215cc. 1.53 is correct.

[oldpro]

It was a 13ci ninja tank I had to go back and fix post I mistakenly put 16ci / Im still not using and anti bounce devices during this test.

Yes, I assumed that from previous post and based my efficiency calculation on 215cc. 1.53 is correct.

Good catch Keith I didnt notice LOL until Bob said something to me.