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Author Topic: Building a better balanced valve  (Read 1379 times)

Bigredhunter00

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Re: Building a better balanced valve
« Reply #30 on: August 04, 2017, 01:11:35 PM »
Hanging out with joe i get to see first hand what the chemicals are doing to him.  Its not pretty at all.  Sorry Joe but i gotta inform them.  His arms are not the only issue.  I thinks hes developing a tumor in his brain the shape of a pellet.  I keep telling him to go see a doc but we know how joe is.
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rsterne

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Re: Building a better balanced valve
« Reply #31 on: August 04, 2017, 03:23:07 PM »
OK, with the tank being 13 CI, that works out to 1.54 FPE/CI.... pretty exceptional for 25gr. pellets at 46 FPE in only a 15" barrel, IMO....  8)

Bob
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Christopher

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Re: Building a better balanced valve
« Reply #32 on: August 04, 2017, 05:00:39 PM »
Hey Bob, taking into consideration the .187 porting and the 15" barrel, along with the 2k psi set point on the reg. Travis nailed the 50%  of the theoretical efficiency didn't he? 

I'll try to show my work even though I usually make a fool of myself doing so ::)

.25 (bore diameter) x .187 (barrel port diameter) x pi /4=.0368 x 15 (barrel length) /12=.046 x 2,000 (reg. pressure)=92fpe

Travis's shot string shows an avg. of 903 fps which is exactly 46 fpe, being right at half of 92. I know that that has been done before, but usually is a dump shot fashion. Travis did it with the ART/Sikes valve (how does ARTSI sound?) with an absolutely stunning efficiency. 
Man I'm wanting one of these valves :D

Chris
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rsterne

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Re: Building a better balanced valve
« Reply #33 on: August 04, 2017, 06:04:41 PM »
Well technically my 50% of maximum rule of thumb is for pellets that are travelling 950 fps (2 FPE / gr.).... but yeah, at 903 it's close enough that congratulations are in order.... My database is pretty much all based on guns of 24" barrel length and over.... It is entirely possible that shorter barrels find it easier to reach, or even exceed that 50% level.... Certainly heavy bullets/pellets can exceed the 50%, we see that a lot (eg. 34 gr. pellets in .25 cal only need to be going 780 fps to hit 46 FPE instead of 910).... No question, however, that hitting the 50% mark with an efficiency of over 1.5 FPE/CI is something I have NOT seen before....  :o

Bob
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oldpro

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Re: Building a better balanced valve
« Reply #34 on: August 24, 2017, 06:28:33 PM »
 I was able to get the final prototype installed and tested in a 22 Mrod today and even though I knew it was going to be good I didnt know how good until today. Ill post strings etc. tomorrowbut for now the WOW factor is a 10++++
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bnowlin

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Re: Building a better balanced valve
« Reply #35 on: August 24, 2017, 06:41:23 PM »
22 or 25 Travis?
Bobn

oldpro

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Re: Building a better balanced valve
« Reply #36 on: August 24, 2017, 06:49:46 PM »
 both
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Christopher

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Re: Building a better balanced valve
« Reply #37 on: August 24, 2017, 07:48:20 PM »
Can't wait  :D

Chris
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oldpro

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Re: Building a better balanced valve
« Reply #38 on: August 24, 2017, 09:54:47 PM »
 A little eye candy for now
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oldpro

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Re: Building a better balanced valve
« Reply #39 on: August 25, 2017, 05:50:03 PM »
 Ok I opened up the TO to .187 and still with stock spring ran the following string. Next I will put in a 10lb spring top to 3k and shoot 55 grain hollow point slugs
Created: 08/25/17 03:56 PM
Description: Mrod
Notes 1: stock gun SS valve
Notes 2: .187 port  2900-1500
Distance to Chrono(FT): 1.00
Ballistic Coefficient: 1.000
Bullet Weight(gr): 34.00
Temp: 85 °F
BP: 29.93 inHg
Altitude: 0.00
#          FPS   FT-LBS       PF
30    783      46.29    26.62   
29    800      48.33    27.20   
28    819      50.65    27.85   
27    836      52.77    28.42   
26    851      54.68    28.93   
25    875      57.81    29.75   
24    877      58.08    29.82   
23    888      59.54    30.19   
22    896      60.62    30.46   
21    902      61.43    30.67   
20    918      63.63    31.21   
19    922      64.19    31.35   
18    930      65.31    31.62   
17    945      67.43    32.13   
16    939      66.58    31.93   
15    941      66.86    31.99   
14    932      65.59    31.69   
13    924      64.47    31.42   
12    913      62.94    31.04   
11    891      59.94    30.29   
10    872      57.42    29.65   
9     870      57.15    29.58   
8     856      55.33    29.10   
7     839      53.15    28.53   
6     832      52.27    28.29   
5     821      50.90    27.91   
4     807      49.17    27.44   
3     790      47.12    26.86   
2     780      45.94    26.52   
1     ERROR 10
Average: 870.7 FPS
SD: 51.8 FPS
Min: 780 FPS
Max: 945 FPS
Spread: 165 FPS
Shot/sec: 0.1
True MV: 871 FPS
Group Size (in): 0.00
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oldpro

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Re: Building a better balanced valve
« Reply #40 on: August 25, 2017, 05:50:42 PM »
 Ok installed 10lb spring and shot 55 grain hollow points
Created: 08/25/17 04:28 PM
Description: Stock Mrod 25
Notes 1: SS valve
Notes 2: 3k to 1750
Distance to Chrono(FT): 1.00
Ballistic Coefficient: 1.000
Bullet Weight(gr): 55.00
Temp: 85 °F
BP: 29.92 inHg
Altitude: 0.00
#          FPS   FT-LBS       PF
19    766      71.67    42.13   
18    771      72.61    42.40   
17    783      74.89    43.06   
16    792      76.62    43.56   
15    804      78.96    44.22   
14    824      82.93    45.32   
13    824      82.93    45.32   
12    837      85.57    46.03   
11    836      85.37    45.98   
10    842      86.60    46.31   
9     846      87.42    46.53   
8     846      87.42    46.53   
7     846      87.42    46.53   
6     826      83.34    45.43   
5     823      82.73    45.26   
4     797      77.59    43.83   
3     789      76.04    43.40   
2     759      70.37    41.74   
1     765      71.48    42.08   
Average: 809.3 FPS
SD: 30.6 FPS
Min: 759 FPS
Max: 846 FPS
Spread: 87 FPS
Shot/sec: 0.1
True MV: 809 FPS
Group Size (in): 0.00
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oldpro

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Re: Building a better balanced valve
« Reply #41 on: August 25, 2017, 05:51:18 PM »
 Didn't have enough 55 grains to run another string so shot some 74 grain hollow points using a 12lb spring
Created: 08/25/17 04:52 PM
Description: stock Mrod 25
Notes 1: 3100-2k
Notes 2:
Distance to Chrono(FT): 1.00
Ballistic Coefficient: 1.000
Bullet Weight(gr): 74.00
Temp: 85 °F
BP: 29.92 inHg
Altitude: 0.00
#          FPS   FT-LBS       PF
15    686      77.34    50.76   
14    702      80.99    51.95   
13    700      80.53    51.80   
12    712      83.31    52.69   
11    733      88.30    54.24   
10    731      87.82    54.09   
9     745      91.21    55.13   
8     756      93.93    55.94   
7     756      93.93    55.94   
6     735      88.78    54.39   
5     743      90.72    54.98   
4     717      84.49    53.06   
3     717      84.49    53.06   
2     704      81.45    52.10   
1     692      78.70    51.21   
Average: 721.9 FPS
SD: 22.7 FPS
Min: 686 FPS
Max: 756 FPS
Spread: 70 FPS
Shot/sec: 0.1
True MV: 722 FPS
Group Size (in): 0.00
  • Mount Shasta Ca.

Christopher

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Re: Building a better balanced valve
« Reply #42 on: August 25, 2017, 06:42:07 PM »
WOW!! That thing will move the air. Amazing how versatile the valve is. Thanks for all the time you take to post this. Looking forward to getting my hands on one of those. Exciting time to be into airguns, watching things just like this unfold.

Chris
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oldpro

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Re: Building a better balanced valve
« Reply #43 on: August 26, 2017, 01:03:29 PM »
  So I vented the poppet thimble and now I can tune to a declining string if wanted. This concludes the non regulated testing now I'll reg it and work on that.
Created: 08/26/17 12:19 PM
Description: Mrod 25
Notes 1: 3K to 2K
Notes 2: SS valve
Distance to Chrono(FT): 1.00
Ballistic Coefficient: 1.000
Bullet Weight(gr): 34.00
Temp: N/A °F
BP: N/A inHg
Altitude: 0.00
#          FPS   FT-LBS       PF
13    886      59.27    30.12   
12    899      61.03    30.57   
11    914      63.08    31.08   
10    931      65.45    31.65   
9     943      67.15    32.06   
8     949      68.00    32.27   
7     970      71.05    32.98   
6     978      72.22    33.25   
5     980      72.52    33.32   
4     988      73.71    33.59   
3     1009     76.87    34.31   
2     1014     77.64    34.48   
1     1022     78.87    34.75   
Average: 960.2 FPS
SD: 44.1 FPS
Min: 886 FPS
Max: 1022 FPS
Spread: 136 FPS
Shot/sec: 0.1
True MV: 960 FPS
Group Size (in): 0.00
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oldpro

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Re: Building a better balanced valve
« Reply #44 on: August 26, 2017, 01:04:05 PM »
 Backed off 3 turns on hammer spring and ran this tune. This valve is truly versatile and very user friendly
 Created: 08/26/17 12:37 PM
Description: Mrod 25
Notes 1: SS valve
Notes 2: 3k to 2200psi
Distance to Chrono(FT): 1.00
Ballistic Coefficient: 1.000
Bullet Weight(gr): 52.00
Temp: 85 °F
BP: 30.10 inHg
Altitude: 0.00
#          FPS   FT-LBS       PF
14    792      72.44    41.18   
13    806      75.02    41.91   
12    812      76.14    42.22   
11    822      78.03    42.74   
10    824      78.41    42.85   
9     834      80.33    43.37   
8     838      81.10    43.58   
7     842      81.87    43.78   
6     841      81.68    43.73   
5     840      81.48    43.68   
4     842      81.87    43.78   
3     831      79.75    43.21   
2     824      78.41    42.85   
1     808      75.39    42.02   
Average: 825.4 FPS
SD: 15.8 FPS
Min: 792 FPS
Max: 842 FPS
Spread: 50 FPS
Shot/sec: 0.1
True MV: 825 FPS
Group Size (in): 0.00
  • Mount Shasta Ca.