Author Topic: Millennium Pumper Production - The Beginning - And The Lousy End (Read 294558 times))

CarsonRatSniper · « **Reply #80 on:** November 08, 2014, 11:04:37 AM »

Manny - It will be over 50 ft lbs...hopefully Bob will be able to figure the math with the larger reservoir.
Bob is helping with the tuning advice on the guns...Jim & myself are doing all the manufacturing and assembly.
Once I get one to him in .25 & .30 caliber his assistance in tuning and data graphing will be *VERY* helpful!

I'm off to work on my buddies roof again today before my 'day' job...then I'm off all next week working with Jim on the guns and cranking out slugs.
The *joy* of being a former roofing contractor!

Mike

Sfttailrdr46 · « **Reply #81 on:** November 08, 2014, 11:28:25 AM »

Roofing contractor , did it part time with a family friend when I was in my 20's for a summer . That is definitely a young mans work !!!

rsterne · « **Reply #82 on:** November 08, 2014, 01:20:38 PM »

Manny, if you look back at the first page of this thread there is a graph showing the three ways I could tune my Millennium Pumper with just a change of preload on the hammer spring.... http://www.gatewaytoairguns.org/GTA/index.php?topic=76600.0

That was with a 28 cc reservoir, the version Mike is producing will have an additional reservoir with a total of 45 cc.... so should have an extra shot, more FPE, or more velocity on the backup shot.... I got 1 shot at 51 FPE, 2 at 45+ FPE, or 3 shots at 40 FPE, with a backup....

Bob

ToRmEnToR · « **Reply #83 on:** November 08, 2014, 03:03:54 PM »

Super sweet.. I'll be following this thread and my bank account, lol..

NickB79 · « **Reply #84 on:** November 08, 2014, 05:08:07 PM »

Given the power being put out by this gun, is it a fair assessment that it would be largely relegated to heavy-weight pellets if ordered in .22-cal?

I'd imagine it would be more difficult to tune it to shoot anything under 15 gr accurately, given that it would probably be sending them close to supersonic with that kind of power. No grabbing a cheap tin of 14.3 gr CPHP's at Walmart if that were the case.

CarsonRatSniper · « **Reply #85 on:** November 08, 2014, 05:17:44 PM »

Just undo the rear RVA cap plug and install a Disco spring - it will be as tuneable in .22 as a factory .22 Disco.

Mike

NickB79 · « **Reply #86 on:** November 08, 2014, 05:34:33 PM »

Really? Wow, that would be nice, actually.

Would it give more shots per fill with that setup (20-25 fpe in .22-cal)?

rsterne · « **Reply #87 on:** November 08, 2014, 05:50:55 PM »

You can tune it for less power by backing off the RVA and/or replacing the hammer spring.... Eventually, you will find that you can't pump to 1800 any more or the initial velocity of the string will be too low.... You can then pump to a lower pressure (easier pumping, a good thing).... OR you can fit a smaller transfer port to reduce the power but allow the full 1800 psi fill.... It will be like any other PCP to tune.... Each caliber will come with the appropriate sized transfer port....

In .22 cal, think of it as a Disco with 1/3rd of the reservoir volume, and hence 1/3 of the shot count.... Pretty much anything you can do power-wise with a Disco (at 1800 psi, but with larger ports) you can do with the Millennium Pumper.... just not as many times....

Bob

Nomadic Pirate · « **Reply #88 on:** November 08, 2014, 06:31:59 PM »

Quote from: rsterne on November 08, 2014, 01:20:38 PM

Manny, if you look back at the first page of this thread there is a graph showing the three ways I could tune my Millennium Pumper with just a change of preload on the hammer spring.... http://www.gatewaytoairguns.org/GTA/index.php?topic=76600.0

That was with a 28 cc reservoir, the version Mike is producing will have an additional reservoir with a total of 45 cc.... so should have an extra shot, more FPE, or more velocity on the backup shot.... I got 1 shot at 51 FPE, 2 at 45+ FPE, or 3 shots at 40 FPE, with a backup....

Bob

If the gun can shoot the Baracuda 31gr at 900 fps for 2 shots count me in for one for sure, 100 %

hypothetical ....( know Bob loves to play with numbers

)

With those specs, how many pumps after one shot to be back at full charge ?

Thanks

rsterne · « **Reply #89 on:** November 08, 2014, 07:37:21 PM »

That's a tall order, but not impossible (900 fps with 31 gr. = 56 FPE).... I did manage a single shot of 868 fps with 42 gr. EunJins = 69.3 FPE (loud and an air hog) with the 28cc reservoir.... I never tried 31 gr. Baracudas, but they should have slightly more FPE than the 25 gr. Kings, and they peaked at 53 FPE, 2 shots at 45+ FPE....

The problem is, like any PCP, as you try and get the last little bit of power, the air consumption goes through the roof.... With a 3 shot at 40 FPE tune, on the 28cc reservoir, I lost 900 psi total (first shot only 280 psi).... Tuned for 2 shots of 45+ FPE, the pressure dropped 730 psi (first shot about 350 psi).... Set for a single shot of 51 FPE, the gun used 500 psi.... Each pump replaced about 25 psi, so that is 11 pumps, 14 pumps, and 20 pumps for the first shot at those power levels....

The new version will have a larger reservoir, which should mean slightly more peak power (but even more air used) if you crank it WFO.... Tuned for the previous power levels, it should mean slightly more efficiency, and more shots (ie MAYBE 5 shots at about 40 FPE instead of 3, 3 shots at 45 FPE instead of 2).... but of course 60% more pumping if you take all the shots because the reservoir is 60% larger.... The bottom line is, you'll just have to wait until Mike builds it and tests it.... If you do manage 2 shots at 56 FPE I would think it would take a lot of pumping to get back to 1800 psi....

If you're talking one shot with Baracudas at 56 FPE and a good solid backup (over 800 fps) I'll stick my neck out and say no problem.... and I'll estimate about 20-25 pumps after the first shot to get back to 1800 psi....

Bob

UCChris · « **Reply #90 on:** November 08, 2014, 07:55:27 PM »

This thing sounds more awesome by the minute!

aom22 · « **Reply #91 on:** November 08, 2014, 07:57:04 PM »

Quote from: rsterne on November 08, 2014, 07:37:21 PM

Tuned for the previous power levels, it should mean slightly more efficiency, and more shots (ie MAYBE 5 shots at about 40 FPE instead of 3,....

3-shots at 40 FPE would ... realistically ... work for me.
Or, to have 2-shots at near 50 FPE available-on-demand ... would be darn-near perfect.

rsterne · « **Reply #92 on:** November 08, 2014, 08:10:42 PM »

The second shot at 50 FPE with Kings.... or even worse at 56 FPE with Baracudas.... may be stretching it.... You may have to accept a slightly lower velocity backup.... or drop the velocity of the first shot just slightly to get two equal shots with a backup.... That's the nice thing, you can choose what suits you best and dial it up with the RVA, within the limits of the platform.... Again, look at this graph of what my original did with a 28cc reservoir....

Then remember that the new version will have a 45cc reservoir (60% larger)....

Bob

Nomadic Pirate · « **Reply #93 on:** November 09, 2014, 04:51:14 PM »

I guess that would do too, at the short ranges I operate 100 fps difference don't really make that much difference on POI.

900 fps with the Baracuda 31gr on the 1st shot and 800 fps for the 2nd would do.

25 pumps to get back to full power is very good too.

rsterne · « **Reply #94 on:** November 09, 2014, 04:58:13 PM »

Might only be 50 fps less on the second shot, Manny.... or two shots at 875 instead of 900.... You'll have to wait until Mike builds and tests it.... at this point it's only an educated guess.... I would PM Mike and ask him to specifically test a setup like that for you and then you will know.... Personally I would be the most interested in what is the most power you can get for two shots of equal velocity, as then you won't be wasting a lot of air on the first shot.... This applies to any pellet and caliber.... As soon as you start tuning for the first shot the fastest, you are never sure how much air you are wasting to get that last few fps on the first shot.... and it can be a lot....

Bob

Bill G · « **Reply #95 on:** November 09, 2014, 07:43:11 PM »

what's the full psi gonna be on this 45cc res.

rsterne · « **Reply #96 on:** November 09, 2014, 07:53:58 PM »

While it would be safe at 2000 psi (or more) I found that pumping past 1800 was too difficult, and that pressure gave me the results I wanted, 3 shots at 40 FPE.... I would personally put a gauge on the gun that only went to 2000 psi if I were Mike and I could get one (but they are impossible to find).... Mike is upgrading the valve screws to 10-32, which is a really good idea as it's easy to overfill the small reservoir if you don't use a regulator.... and of course if you are using a 3000 psi tank and the regulator fails, guess what, you end up with 3000 psi in the gun.... The threaded 16 gr. CO2 cartridge that I used to increase the reservoir size is rated at 250 bar MSWP and 500 bar burst, so it's not an issue....

Bob

Chako · « **Reply #97 on:** November 09, 2014, 08:08:06 PM »

Would it be a benefit to use a regulator in this gun?

rsterne · « **Reply #98 on:** November 09, 2014, 08:27:43 PM »

Basically useless, the reservoir is much too small.... Tethering it to a regulated tank, on the other hand, will work extremely well....

Bob

Chako · « **Reply #99 on:** November 09, 2014, 09:34:48 PM »

Ok. isnt the indy regulated? Do you know the volume of the reservoir on it?

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Millennium Pumper Production - *The Beginning* - And The Lousy End

Author Topic: Millennium Pumper Production - *The Beginning* - And The Lousy End (Read 294558 times))

Nomadic Pirate

Nomadic Pirate

Millennium Pumper Production - The Beginning - And The Lousy End

Author Topic: Millennium Pumper Production - The Beginning - And The Lousy End (Read 294558 times))