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

[Rivers3Plinker]

I knew that was coming Just remember to alternate pumping arms regularly so one doesn't get bigger that the other.  I see a lot of pumping in the future

I was going to say "When I pump with my left arm I pump like a girl!" but that would be politically incorrect and sexist.
Don't want to go there and offend the girls on this forum.

[Sfttailrdr46]

I knew that was coming Just remember to alternate pumping arms regularly so one doesn't get bigger that the other.  I see a lot of pumping in the future

I was going to say "When I pump with my left arm I pump like a girl!" but that would be politically incorrect and sexist.
Don't want to go there and offend the girls on this forum.

I think that a few of the young ladies here are in much better physical condition than some of us old farts

[c670809]

Went out shooting today and spent more time thinking about the Millennium Pumper than shooting ;-)

How's the testing coming?

[CarsonRatSniper]

I received the trigger guards from Norm - they are polished aluminum

They bolt directly to the trigger block - the stocks are already inletted for them.





I am going to try some longer range testing tomorrow (finally!) with Kings and see how she does...then a complete tear down to replicate parts so we can get them out for anodizing Tues or Wed.

I will post group pics tomorrow some time.

Mike

[CarsonRatSniper]

Ok guys, there's a new development with the Millennium barrel construction...they will be held in tension using something similar to Bobs Belleville assembly - the sleeves *will not* be permanently bonded.
We are doing something called *Viscous Dampening*

Its all Jim's Baby - he wants the most accurate air rifle in the World if its leaving his shop and refuses to permanently bond the cf sleeves to the barrels...he has assured me his system is the best *period*!

Bear with me folks, its going to be worthwhile! This is outside the box engineering but Jim already has done mountains of R&D on this system and it works better than any other type.
The harmonic vibrations are absolutely nullified.

I will post more details as we get into barrel construction - and I'll be sure to include lots of pics!

Mike

[Monkeydad1969]

Wonder if that can be put onto a Disco barrel pretty easily.

Joe

[Hanabata808]

Its all Jim's Baby - he wants the most accurate air rifle in the World if its leaving his shop and refuses to permanently bond the cf sleeves to the barrels...he has assured me his system is the best *period*!
...
The harmonic vibrations are absolutely nullified.

I will post more details as we get into barrel construction - and I'll be sure to include lots of pics!

Mike

[Tommy]

I am wondering if the trigger guard will fit the Disco
Tom

[rsterne]

Sounds interesting, Mike.... Look forward to seeing the details.... If he's not using Bellevilles, how does he look after the different rates of expansion with temperature between CrMoly steel and Carbon Fibre?.... That's why I gave up on the idea of just torqueing to tension the barrel....

Bob

[CarsonRatSniper]

I have to check with Jim before I disclose the process - he said I could tell you *Viscous Damping* for now.

Mike

[rsterne]

Of course....

Bob

[nervoustrigger]

Converting vibration to low grade heat, I assume.  It's a common technique for sound attenuation.  I'm interested in hearing how it works out!

[CarsonRatSniper]

We, of course, will test one before we build all the barrels that way.

Mike

[aom22]

I been avoiding interjecting myself into the issue of a carbon-fiber barrel shroud.
Now, that the a Belleville Spring Washer system will be employed to adjust
barrel tension ... here's my opinion.

First, I need to establish my credentials regarding the opinion I'm about to put forth.
I have an Associated of Applied Science Degree in Mechanical Engineering Technology.
And, an Associates of Applied Science Degree in Plastics.
That's right ... like in the movie "the Graduate" ... Plastics.

Carbon-fiber based composite materials are much stronger under tension and less-so under compression.

GRAPHLITEŽ carbon rods

Continuous rigid composite rod densely reinforced with highly oriented carbon fiber in a cured epoxy resin matrix.

Tensile Strength 320 ksi / 2.34 GPa
Compressive Strength 270 ksi / 1.90 GPa

Advances in sizings and surface treatments for carbon fibers

However, this is true of virtually all other materials.

But, high-carbon steel should remain more stable under long-term compression loads versus most composite materials.
Why is this?
Because of the resin or binder agent associated with a composite material - the plastics element.
The purpose of the resin is to hold the shape of the carbon-fiber fabric.
And, to transfer any applied load to the fiber-matrix.
In the process of transmitting the applied load ... some flex, give or shift is involved.

Under a continuous load, the flex or give of the plastic resin persists until the fiber-matrix absorbs the stress.
My point, under continuous compression ... the resin continues to very gradually move, flex or give ... it
will not take a permanent immovable set.

Moreover, the rigidityof the plastic resin is not constant.
Factors such as temperature changes (high or low) effect plastic flow.
As I said before, under a continuous load, the resin may continue to move, ... but, at a varying rate depending on the ambient temperature.

On-the-other-hand, steel or other metallic materials tend to be more stable under compression and are less effected
by normal temperature variations.

I believe, for a thin-walled shroud to remain stable under continuous compression ... steel or other metallic material
would be a better choice for use as a barrel tensioning shroud.

However, a close-fitting carbon-fiber sleeve would give better service as an effective vibration damper.

[rsterne]

I can see your point about the CF composite moving under constant compression.... It will be interesting to see how much and how fast that occurs.... The nice thing about the Bellevilles is that I can back off the tension, counting the turns/degrees of rotation of the nut, until the pressure is released.... Comparing that to the original setting should give a measure of the amount of "set" the material takes, and how long it requires to do that.... It may be that the load needs to be backed off during storage.... CF composites are used a lot in yacht masts, which is where I cut my teeth in the technology, and of course in that use, they are nearly a pure compression member, all the tension loads are taken by the rigging.... So although they may be better in tension than compression, they certainly work well in both.... Otherwise, tubes in bend, such as fishing rods, and masts, would fail by buckling....

If taking a set becomes a problem, I can easily switch over to either CrMoly tubing or 6061-T6, both of which have nearly identical thermal coefficients.... The other disadvantage to the CF composite is that it is nearly thermally stable, compared to metal, which increases the need for the Bellevilles.... This tensioning idea using Bellevilles is still in it's infancy, I have a lot to learn about it.... So that we don't drag Mike's thread too far off course, perhaps you can comment in either the thread I started about this idea, or in my 7mm Build in the Big-Bore gate where I plan to put this idea to the test....

Bob

[CarsonRatSniper]

I put my Center point 4-16x40 on the test rifle - I used UTG quick release rings that came with my Bug Buster scope.



I set up at 50 yards on the hood of my Jeep and shot a couple of groups...





It wasn't the best rest as it was still a bit wobbly...The average at a lasered 50 yards was 1/2" - 3/4" with Kings.
This is just the barrel screwed into the breech - the groups were strung vertically and most had 3 pellets all touching then a couple high or low.
I'm going to have to wait until I get to my actual range with the rifle before I do anymore longer range testing.

Mike

[Habanero69er]

That's a nice looking rifle Mike.

[CarsonRatSniper]

Thank you!

Wait until its all finished

Mike

[aom22]

It wasn't the best rest as it was still a bit wobbly...The average at a lasered 50 yards was 1/2" - 3/4" with Kings.

Mike, how about posting the targets ... I'd love to see them.

By the way, that's a very good-looking rifle - very purposeful appearing.
The combination of aluminum sheen, the contrasting carbon-fiber texture
and the various colors of the stock ... look great - very appealing to the eye.

[CarsonRatSniper]

I measured groups, wrote down sizes and scrapped the targets - I still have my very first 50 yard group I shot and will post it later today. I don't want folks thinking this is how the final rifles will shoot.
I'm only collecting data before we work on the barrels to get a baseline so we can measure what our process did to improve accuracy - they still need to be lapped and sleeved + I need to draw up the new Belleville muzzle assembly and machine them.
If I get a good day without wind and time on the real range before we finish the barrels I will shoot it again the way it is.
I will post pics of proof targets once they are finalized.

The stocks are not finished yet and all aluminum parts need anodizing still...we still have a ways to go.

Mike