*Poll* High Quality 6.35mm Air Rifle - PCP vs Pumper

[cclingma]

    I will sell the diamond earnings my grandmother left for me to give to my future wife. No doubt she would understand.

It's a pumper, it's a PCP, it's a repeater, it's high energy.  How could she not understand?

[aom22]

No and no!.... I don't think Mike has any plans for .177....

     TJ's Barrel liners are the ticket for a conversion, see attached photo
     TJ's Enterprises
     3652 Neltner Rd
     Alexandria, KY 41001
     (859) 635-5560     
     

I think I see why there won't be a .177 anytime soon.
That is, a Millennium Pump/PCP with a TJ's barrel in .177 ... the only barrel liner
TJ lists in .177 has a 1:9 twist - firearm specification.
 
It is also interesting to compare the T.J.'s bore/land specifications with Lothar-Walther barrel specs.
T.J.'s and LW dimensions in .22 caliber vary somewhat - inparticular, the bore diameter.

[rsterne]

Barrels can be obtained from other sources, such as LW.... IMO the reason (for no .177) is that the Millenium Pumper was primarily designed to push MSPs to a whole new level of power, and the only way to harness that in a .177 would be to run extremely heavy pellets (13+ gr.).... That is somewhat akin to building a Nascar engine and then putting a restrictor plate on it.... It has a specific and limited purpose (that can provide a lot of entertainment) that had no interest for me, and hence wasn't on the radar when I did the original build.... I barely even considered a .22 cal at the time, although I can understand including it from a marketing point of view.... I'm sure that once Mike builds some and they end up in the hands of shooters, both larger and smaller calibers will emerge.... It's all economics at this point, too many changes, and going in too many directions at once, will result in no profit and ultimate failure of the attempt, IMO....

Your prices on the TJ's liners are way out of date, BTW.... and there are more sizes available now....

Bob

[aom22]

... IMO the reason (for no .177) is that the Millenium Pumper was primarily designed to push MSPs to a whole new level
of power, and the only way to harness that in a .177 would be to run extremely heavy pellets (13  gr.).... Bob

Bob, one of the main attractions of the a pumper to me is the ability to control power-output.
For a .177 caliber Millennium Pumper to be more useful, the ability use mid-weight pellets is the the key.
A MSP would can make this possible ... just add fewer-strokes of compression.
 
For my use, magnum-power would not be needed ... all of the time.
In situations such as plinking or quiet backyard target-shooting much less-power would be required.
With a lower-power requirement, there would-be less of a work-load to keep the Millennium under optimum compression
for the task at hand.

[rsterne]

Yes, it could be done by using less pressure and reducing the hammer strike correspondingly.... longer shots strings at less power and/or fewer pumps per shot.... Everybody has a different use, and the gun could be tailored to suit.... For your purposes, a 397 ACP would do as well.... It is not possible with any air-conserving design to just pump less because the hammer strike ends up being too much for the lower pressure and the velocity actually goes up (initially) before the gun becomes a pump-and-dump.... losing the efficiency advantage, in fact big-time because of the large reservoir.... You have to retune the hammer strike along with the lower pressure you want to use, maybe even change springs.... and then resight the gun for the new POI.... It's a lot of fiddling to change modes, IMO, but certainly possible, just as it is with a PCP.... Not my cuppa tea, but if you can only have one gun to do it all, is certainly possible....

When people think of an MSP they tend to think of a pump-and-dump gun where pumps in = power out in a simple, straight-forward fashion.... Think of this gun as a PCP with an onboard pump and you will get a better idea of its strengths and weaknesses.... Possible, yes?.... Practical?, that's in the eye of the beholder....

Bob

[aom22]

.... For your purposes, a 397 ACP would do as well ... Bob

Yep, I've looked into an ACP.
Unfortunately AoA only sells the 392 version.
I prefer a .177 or .20 caliber, considering the relatively low FPE a ACP produces.

By-the-way, Steve-in-NC is willing to mod a 397.
But, he willl only due-so ... three at a time.
I know, I've traded a few emails with him on the topic.
 
Also, one interesting feature of the ACP, his pumper is equipped witha a dual-sear trigger
allowing regular-power and a lower-output setting - neat.
 

[aom22]

You have to retune the hammer strike along with the lower pressure you want to use ..... Bob

Then, the ability for to the owner to easily adjust the hammer-strike ... this appears to be the key for practical lower-power output.
Hmmmm, having the ability to easily manipulate the hammer-strike may help in fine-tuning the air rifle to the pellet for best accuracy.

[rsterne]

Correct, and Mike will be providing an RVA (rear velocity adjuster, aka power adjuster, aka preload adjuster) that also allows swapping out the hammer spring without stripping the back of the gun, only pulling out the adjusting screw.... Any PCP without one is seriously handicapping the adjustability and tuning, IMO.... and for an ACP they are necessary to balance the velocities over 1, 2, 3, or "X" shots depending on your needs.... Go back to Reply #4 on Page #1 to see the shot strings I had with just a hammer preload adjustment....To make a huge change (eg. from a 40 FPE .25 cal to a 10 FPE .177 cal) may well require changing the spring, particularly if you want to detune to a much lower pressure (with easier pumping)....

Bob

[TleVta]

Hi Bob,

Don't mean to change the subject, but did you weigh your gun after you finished it?

[rsterne]

According to the original thread, it weighs "7.25 lbs. without the scope"....

Bob

[grhouse]

I've been away from the Forum for a few weeks and just saw this thread. WOW! I love the idea and would like to have something like this. Has a price ever been decided on? Also, How much power will it take to pump the rifle up to full capacity? I'm getting older and weaker from arthritis and other joint issues and recently bought a break barrel from Umarax. I could not cock the dang thing very easily at all. I mean I had to strain to do it and I was worried I'd break something in the gun but it was only my joints popping. Would someone like me even be able to use this rifle? I have a Disco but really like the idea of not having to carry a fill tank with me to shoot and I've modified it to 25 CAL so I only get about 12 good, reliable shots per fill. I need this rifle if I can pump it! Gene

[MRT949]

OK YOU HAVE MY WHEELS TURNING.
 SIGN ME UP

[CarsonRatSniper]

I have no idea what the pumping force will be - I would imagine it will be similar to a Steroid 392 @ 14 pumps or a bit harder...Bob would have to chime in on that one.

We're cutting breeches! 

7075 aluminum with a stick magazine. The Picatinney rail will continue all the way across the top of the breech = no traditional loading port...there will be a 'rectangle' milled through the side of the breech for the stick mag to index into. The mag will also be made of 7075 aluminum and offer *full* support just like a breech block.
The end of the breeches will be 1/2" longer than a factory steel breech (6 3/4" long) and will be machined round to accept a barrel band - just like Grant Stace used to make his breeches.
This design also does away with the 4-48 transfer port screw

The breeches and the barrels will be threaded. The bolt will be .375" stainless and be reduced for the appropriate caliber in the magazine/barrel portion.
Transfer ports will be made of 5/16" Delrin with the appropriate transfer port hole sized for caliber.

Want to change calibers? Remove the top end - unscrew the barrel - remove the bolt - install the bolt/barrel/magazine/transfer port for the caliber you want and reinstall.

Calibers will be .22, .25 & .30  Yes I said it...a .30 caliber pumper!

We are making 2 complete rifles with Blaster stocks in Pepper laminate.

All aluminum parts will be bead blasted to reduce glare.

Once they are tested, data collected and we *get it out there* we are producing these guns those first 2 rifles will be sold to finance the next run of guns.

I'm hoping to have barreled actions to send to Norm for stocks in 2-3 weeks.

I will start a new Millenium Pumper build thread as soon as I have some pictures to share.

I won't have any pricing until we make all the parts and look at what each part costs us to make.

These are *NOT* going to be one off builds! Jim & I will be marketing them to retailers and we are hoping to go into full time production with the rifles.

We're getting close boys!!!

Mike

[UCChris]

I'm stoked to see how this goes!

[farmerjoe99]

Thanks for the update Mike!!
Looking forward to more info and pics!
Keep up the good work
Joseph

[rsterne]

Glad you announced the .30 cal, Mike, I've been busting at the seams wanting to say something.... *LOL*.... It's a pellet shooter, of course, using the 26" twist barrel that Sean and I designed, which is a true .300 cal groove with 0.294" lands designed for the 45-50 gr. JSB Exacts (also marketed by FX and Daystate under their own labels).... We won't know what kind of FPE we can achieve until we do the testing, but my spreadsheet says about 60-65 FPE (750-800 fps) should be possible, and the larger 45cc plenum should make that work OK.... Whether we can get that kind of power for 2 shots (with a backup) remains to be seen.... as we're in totally new territory here....

I like the rigidity of the breech design with the continuous rail and the rectangular window for the magazine, Mike, that sounds great.... I'm looking forward to seeing them.... This is getting EXCITING !!!

Bob

[CarsonRatSniper]

Yeah, I'm pretty stoked Bob!
We also raised the breech .215" over the tube so the .750" OD CF sleeved barrels will still be happening.
They will index and tension against the breech face where the barrel band is located.

If you want a true repeating .30 cal we're back to tethering to an 1800 psi regged tank in a bag or small day pack.

The .22 cal barrels Mike sent me are the slow 1:22 twist - I will order some of the 1:16's once these are tested so we can see how the .22 heavies perform.

I will conduct my initial testing with a 22ci tank...then see what one of those 90ci 4500 psi tanks from Tim will do in regards to shot count.

I should have reportable data by the end of November.



Mike

[rsterne]

Hey, two shots from a .30 cal with a backup would be a pretty deadly setup for hunting, and I think it's possible to do that, especially with the new 45cc reservoir....

Bob

[CarsonRatSniper]

I can't wait just to have a *.30 cal Pumper*!

You certainly don't need the tank - I'm just pointing out (again LOL) the versatility of this gun.

I don't even care if its 30 pumps or something per shot...its gonna be *awesome*!

 

Mike

[rualert]

     I'd also be interested in the Disco bottle conversion setup in addition to the pumper. Just happen to have a couple of those 13 cu.in bottle lying around for, and from various projects.

Casey

Plus any of you programmers out there we have a pretty active thread on some basic open source software for now at least the Chrony brand chronographs.  ( sorry not trying to threat jack, just looking for some more programmers, so we can build something nice and basically free for the community)