Marauder porting greater than .1875" without moving seat forward
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Marauder porting greater than .1875" without moving seat forward
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Topic: Marauder porting greater than .1875" without moving seat forward (Read 10026 times))
shorty
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Real Name: Tim
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #20 on:
May 23, 2017, 05:14:12 PM »
I am taking things much slower now and trying to think out the work before doing it ( I am very impatient ). I also have a deeper appreciation for you machinists that work on these kinds of things.
If level one is opening up a stock valve to flow with .1875" porting, then plugging and pushing the seat forward is close to level 6 in my book.
I got the .1875" punch broach (real one) in last Saturday. Boy I am mad with myself for not following out the plan I had originally set for punching a square hole. That punch broach slipped in like butter and came out just as easy.
Looks like it's all in the design. Tapered..... Duhhh.... When I made mine, they were just straight. So, my broaches just wedged themselves in.
Here's a pic of a real square broach.
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Palm Coast, FL
shorty
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Posts: 1936
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Real Name: Tim
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #21 on:
May 26, 2017, 05:27:29 PM »
Still working the the plug.
I made a couple out of some mild steel for the first couple times and then started noticing that when left over night in the garage, they would begin to surface rust. I figured now that using that steel as a plug is a big no-no and decided to make a plug out of brass.
I just hate turning brass.
Anywho,
I opened the inner casing of the valve to .605" (only half way) instead of the .5" area for the plug. Made the new plug from brass, oring'd it (both ends), gave it a throat of .261" and drilled the rest through for the valve stem.
I am kind of stuck on the valve stem hole. I am kinda thinking that the valve stem is a little bigger (.001" maybe) than the 1/8" I though it always was supposed to be. I put three 1/8" bits threw it along with a 1/8" reamer and that darn valve stem still won't get in that hole (hey!). On a scrap piece of metal I tried my .128" drill bit and it was just way too loose.
Gonna have to find a little bit bigger reamer I guess.
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Palm Coast, FL
ackuric
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Sharp Shooter
Posts: 943
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Real Name: Matt
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #22 on:
May 27, 2017, 03:52:23 AM »
Curious what your end game is with this valve? Slug shooter? .30 cal? Or staying .25 cal? The title of the thread says WITHOUT moving the seat forward and now you're moving the seat forward? Confusing but GL.
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Westminster Colorado
.25 Ackurized 26.75"- 40" M-rod custom carbine 4.7lbs
.04" Valve Stem / .2255" Seat / .212" Ports
Peek Poppet @ .25" / Lane Reg / Custom SSG's
5lb Valve Spring / 25 gr Hammer / 25cc Plenum Ext. / 7.7# hammer spring
16 Shots @ 60 FPE - 1.2 FPE/CI (33.9 gr)
32 Shots @ 52.5 FPE - 1.55 FPE/CI (33.9 gr)
48 Shots @ 41 FPE - 1.88 FPE/CI (25.4 gr)
72 Shots @ 25 FPE - 2.02 FPE/CI (19.91 gr)
shorty
Expert
Posts: 1936
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Real Name: Tim
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #23 on:
May 27, 2017, 08:20:17 AM »
Not sure what I am gonna do.
Since I screwed the pooch on the valve with the square hole, I was thinking I may just try and finish it off with the seat moved forward and then ask for a trade from someone for a stock valve so I can continue with the square hole.
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Palm Coast, FL
shorty
Expert
Posts: 1936
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Real Name: Tim
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #24 on:
May 27, 2017, 06:22:36 PM »
Finally got the valve stem in the BRASS plug.
Not sure what to do next. Drill and tap for the 10/32's or throw a plug in the exit port of the valve to close up the metering screw and make a clean passage way.
That stock valve stem is no way .125".
As this is going on I am trying to think how to test the valve for leak "out of the gun".
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Palm Coast, FL
ackuric
Banned Members
Sharp Shooter
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Real Name: Matt
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #25 on:
May 29, 2017, 01:00:27 AM »
I believe the stems are 3.2mm / .12599
I could be wrong.
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Westminster Colorado
.25 Ackurized 26.75"- 40" M-rod custom carbine 4.7lbs
.04" Valve Stem / .2255" Seat / .212" Ports
Peek Poppet @ .25" / Lane Reg / Custom SSG's
5lb Valve Spring / 25 gr Hammer / 25cc Plenum Ext. / 7.7# hammer spring
16 Shots @ 60 FPE - 1.2 FPE/CI (33.9 gr)
32 Shots @ 52.5 FPE - 1.55 FPE/CI (33.9 gr)
48 Shots @ 41 FPE - 1.88 FPE/CI (25.4 gr)
72 Shots @ 25 FPE - 2.02 FPE/CI (19.91 gr)
shorty
Expert
Posts: 1936
yes
Real Name: Tim
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #26 on:
May 30, 2017, 09:48:50 PM »
Got the plug sealed into the valve body finally by 2 o-rings.
Looks like it will be a little tricky assembling the valve into gun because the only thing holding the plug in the valve body are the three 10/32's. So I am thinking some long 10/32 set screws to hold it in place while assembling and then remove one and replace it with the 10/32 retaining screw 1 at a time.
Still not sure if it will hold air yet and I have to work on the exit part of the valve next before popping it into a gun.
Boy this is a lot of work.
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Palm Coast, FL
shorty
Expert
Posts: 1936
yes
Real Name: Tim
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #27 on:
May 31, 2017, 07:17:23 PM »
Getting closer now and getting more excited.
As I have been working on the valve, I have been trying to come up with a fast easy way to give the HUMA with gauge port a larger plenum.
Today is a two-fur. Almost complete plenum extension and the valve that is capable of an exit port of .245".
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Palm Coast, FL
rsterne
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Bob and Lloyd
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Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #28 on:
May 31, 2017, 08:48:28 PM »
I think you should be able to thin out the wall on the plenum extension by about half.... You don't want to go too thin, or this can happen....
Scott (Motorhead) should be able to advise you on a suitable wall thickness to withstand the end force from the pressure differential across the regulator....
Bob
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Coalmont, BC, Canada
🇺🇦
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦
Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).
shorty
Expert
Posts: 1936
yes
Real Name: Tim
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #29 on:
May 31, 2017, 09:01:57 PM »
Yup,
I remember that picture from when I was doing the 22 synrod.
The reason why the wall thickness is so much at the ends of the plenum spacer is because I am going to part the HUMA plenum in half and then turn down the ends of the extension to accept an O-ring and slip into the parted Huma plenum. The middle of the plenum spacer will be thinner.
This way the plenum should still seal and be able to vent through the gauge port. I am only doing it this way because I can not internal thread or even feel like bothering with it.
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Palm Coast, FL
ackuric
Banned Members
Sharp Shooter
Posts: 943
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Real Name: Matt
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #30 on:
June 01, 2017, 12:10:34 AM »
.245"
Sweet baby...lets get that puppy shootin'!
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Westminster Colorado
.25 Ackurized 26.75"- 40" M-rod custom carbine 4.7lbs
.04" Valve Stem / .2255" Seat / .212" Ports
Peek Poppet @ .25" / Lane Reg / Custom SSG's
5lb Valve Spring / 25 gr Hammer / 25cc Plenum Ext. / 7.7# hammer spring
16 Shots @ 60 FPE - 1.2 FPE/CI (33.9 gr)
32 Shots @ 52.5 FPE - 1.55 FPE/CI (33.9 gr)
48 Shots @ 41 FPE - 1.88 FPE/CI (25.4 gr)
72 Shots @ 25 FPE - 2.02 FPE/CI (19.91 gr)
shorty
Expert
Posts: 1936
yes
Real Name: Tim
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #31 on:
June 01, 2017, 10:21:34 PM »
I am kind of glad I decided to start working on the Huma with gauge port plenum extension. I have been following triggertreats post with the new cobra valve that is now supporting .22" porting.
http://www.gatewaytoairguns.org/GTA/index.php?topic=126118.0
I have also been following ackuric's post as well .
http://www.gatewaytoairguns.org/GTA/index.php?topic=125378.0
Something interesting going on that has always made me have a hunch about the "historical" ways of tuning a regulated gun in regards to TP size. I have always learned by the pros here (before regging both my guns) that opening up everything as much as possible is the best way to go. Pbguns and I learned this first hand back in January when the 40/40 was developed by us. This is not a good way to develop or tune a regulated Mrod for the highest efficiency and power level.
So,
I know this post started with "square hole" and turned into this but hey, it is what it is. I am gonna try and finish the plenum extension first and see where it takes me. The good thing will be is that I should be able to deliver enough data to put up a comparison between stock plenum and modified plenum with no other changes to the gun nor regulator pressure setting.
My hunch is that power will definitely go up and efficiency should increase as well. We all know these thing will happen in regular guns but this gun is already running 1.77+ efficiency at 40 fpe and around 1.52 efficiency at 50 fpe running a 1950 psi. I am really looking forward to doing some testing this weekend if I finish it up. The competition is starting to stack up.
For the plenum extension, it's looking like just around 1.5" longer at the same ID. I plan on a double O ring on both sides and a small amount of epoxy to hold everything together.
Hopefully that will be tomorrows work.
«
Last Edit: June 01, 2017, 10:24:19 PM by shorty
»
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Palm Coast, FL
shorty
Expert
Posts: 1936
yes
Real Name: Tim
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #32 on:
June 03, 2017, 10:58:59 AM »
Got the o rings in on the plenum extension and epoxied the parts together this morning. Boy I hope this holds together and hope everything is as straight as possible. I figured if it doesn't work out with being straight or if an o ring doesn't seal I can always hit it with a torch to break the epoxy and start over or maybe I can true it up on the lathe if the epoxy holds.
It's looking like I will be going from 23/25 cc plenum to just at 40cc or slightly under. This is adding 1.4"/1.5" of length to the stock huma gauge port regulator. Looks like I will be losing about 20/21cc's in the HP side putting it at the now 169/170cc.
I really don't want to guess what to expect or make any claims yet but I am sure getting anxious. This should be a great example of the 1/2cc to 1cc per fpe rule with in gauge regulators.
My max power (before the regulator) at 2400psi was 70 fpe.
My max power before (with the regulator) at 1950psi with 43 eujins was 60/61fpe and with 34 grain JSB's was 56/57fpe.
On a side note for the guys reading and wondering where this is going, I am chasing down that 30 shot 60 fpe tune and trying to get a higher efficiency at lower power levels. I know I won't get the shot count with the hp side being at 170cc's but that's what a tube extension is for to bring it back to 215cc's.
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Palm Coast, FL
shorty
Expert
Posts: 1936
yes
Real Name: Tim
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #33 on:
June 03, 2017, 05:53:29 PM »
Regulator is now in the gun and charged to 1500 psi. Got to wait for the hand pump to cool down. This is probably the most nerve racking part of doing these kinds of mods to a gun (LEAK TESTING ).
Please don't leak.
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Palm Coast, FL
shorty
Expert
Posts: 1936
yes
Real Name: Tim
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #34 on:
June 03, 2017, 06:45:14 PM »
Starting to get a little disappointed
. The reg settled in around 1750/1850 and running a knee with 34.95 Jsb put it at 53 fpe for a max
.
I have not seen anything positive from going from 1/2cc to 1cc fpe YET.
It could be that the before numbers were with a reg setting at 1950/2000psi but still, I am a little disappointed.
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Palm Coast, FL
Motorhead
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Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #35 on:
June 03, 2017, 06:58:38 PM »
Tuning chores with PCP's and hand pumping ... No thank you !!
Hope it is leak free
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rsterne
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Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #36 on:
June 03, 2017, 07:28:11 PM »
Increasing the plenum from 25 cc to 40 cc should give you the SAME power with about a 100 psi lower setpoint.... If your pressure is 200 psi lower than before, you can expect to lose 3-4 FPE.... To see a noticeable increase in FPE from the larger plenum, you will need to run the same setpoint you had before....
Bob
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Coalmont, BC, Canada
🇺🇦
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦
Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).
shorty
Expert
Posts: 1936
yes
Real Name: Tim
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #37 on:
June 04, 2017, 08:47:59 AM »
Yup, I have to get the regulator back up to where it was originally. Unfortunately, when I screwed with the reg setting a while back and thought I screwed the pooch with it, the little scale to indicate the pressure setting was removed. So, it's fill,check, and re-adjust to get it back to where it originally was. It would be real nice to have a bench test rig for the reg just about now.
Well it seems like the gun held air at 2500psi last night. Busy day with the honey do list but the plans are to shoot it down to empty at 40 fpe and see where the shot count and efficiency is. If I still have time I may attempt to adjust the reg again up to 2000/2100 psi.
As soon as these things get sorted out I will start working on the valve again. All I have left is the exit part of the valve.
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Palm Coast, FL
shorty
Expert
Posts: 1936
yes
Real Name: Tim
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #38 on:
June 04, 2017, 01:26:20 PM »
Shot a string down.
Starting pressure 2500psi, reg set approximately 1850 psi (hard to see) using 25.39's. 16 shots at and efficiency of 1.56 just a hair over 45 fpe. That should give a steady under 2.5% ES for 28 shots on regulation currently.
Shooting it down, ending pressure was around 750psi and the last shot was 701 fps.
Can't really complain about it anymore. Comparing it to triggertreats gun with the cobra valve in it he got a 1.6 efficiency using 33.95's at a reg setting 2050 psi.
Going to try and up that reg pressure now to 2000/2100psi.
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Palm Coast, FL
shorty
Expert
Posts: 1936
yes
Real Name: Tim
Re: Marauder porting greater than .1875" without moving seat forward
«
Reply #39 on:
June 04, 2017, 02:38:50 PM »
No more testing for today.
I was able to change the reg setting to just above the 2000 psi mark and put a 2500psi charge in. It's looking like 2050/2100 psi reg setting. Man I need some glasses.
Ran a knee using the 43.2 eujins and things are looking good. maxed out at 65FPE
Not sure when I will be able to run some strings to check for efficiency but I am sure it will be impressive.
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Palm Coast, FL
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Marauder porting greater than .1875" without moving seat forward