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

[CarsonRatSniper]

I filled it to 1800 psi and got 5 shots
885, 868, 836, 807, 768
Start 1800 psi - End 1400 psi
This was -3 turns from coil bind.

With the hammer spring -1/2 turn from coil bind:
Kings - 1800 psi = 905 fps (200 psi) / 2200 psi = 945 fps (200 psi)
31 gr Spitzer - 1800 psi = 830 fps (175 psi) / 2200 psi = 842 fps (200 psi)
37 gr - 1800 psi 778 fps (150 psi) /2200 psi = 785 fps (175 psi)

That's using a lightened Prod hammer which is what I'm going to use - I will tune for a King @ 850 fps tomorrow morning and see what the string looks like.
I will weigh the rifle once its fully assembled.

Mike

[Monkeydad1969]

Is that pumper using the same valve we are getting from you?

Joe

[CarsonRatSniper]

Yep...the *exact* same valve.

I'm going to install one in my .25 Challenger Double Tube and see if she'll do 100 ft lbs.

Mike

[Monkeydad1969]

Cool. Let us know. 

[CarsonRatSniper]

Ok, I filled to 1800 psi, disconnected the line from the rifle and ran a string to see how many shots I'd get from 1 fill.
The rifle was tuned with the RVA 5 turns out from coil bind and all shots were using JSB Kings.

Here's the string:
Start 1800 psi
857.5
842.1
818.5
809.4
781.6
754.4
711.5
668.5
620.1
519.1
End 400 psi

Needless to say I'm very happy with how many usable shots I got with such a small reservoir and only 80 fps spread between shots 1 & 5.



Here's a JSB King I loaded then pushed back out to check the leade engagement:



The head is engaging the rifling and the skirt is in contact with the smooth portion - the leade has been optimized for Kings and my 37gr Spitzer slugs.

Accuracy testing in a day or two minus the cf sleeving using a .560" OD barrel - then testing with a cf sleeved barrel then with a tensioned 1.25" cf shroud over the cf sleeved barrel...that way we can document what differences each modification makes.

I will have a stocked rifle for testing tomorrow...I'll post pics tomorrow.

Mike

[c670809]

I'm excited at that we are getting closer. I have one on order and I've been waiting not so patiently ;-) . . . glad it's coming together.

I assume with some more testing we can either get a little more power or get a long shot string?

Here's the reason I asked. I've read every thread I could find on Bob's gun and unless I'm mistaken his gun has about half of the storage capacity as the new design but Bob was getting three shots at or within a few fps of  850 fps. With twice the air capacity we are only getting 2. I assume it will be a simple spring or adjustment change?

Here is Bob's chart if I linked to it correctly:



There seems to also be a considerable difference in top power. At 2000 psi Bob's was pushing the JSB's at just over 1000 fps and at 1550 they were still running over 900. It seems it's taking about 400 psi more to get the same power.

I'm excited that it's all coming together. Can't wait to go shoot.

Thanks

[CarsonRatSniper]

I'm using a different RVA/hammer/spring than Bob did...I'm *just* beginning tuning and will finalize what we will use in the rifles before they ship.
I may add weight to the hammer via a carbide spring guide.

Its coming along

Mike

[rsterne]

IMO, Mike's string indicates almost exactly the same performance I was getting, at the same pressure.... Look at the blue line on the graph, three usable shots of ~835-860-840.... If Mike backed his preload down JUST a whisker to drop the first shot to the about same 835 fps I had, I'm guessing he would have 4-5 shots within 4% ES.... In fact, I'd pretty much lay money on it.... If you want more power, just pile on the preload and burn a bit more air.... That's all I did with the red and black strings above.... I'm delighted that these initial results show consistency with my prototype....

Bob

[CarsonRatSniper]

Ok, weight unscoped is 8 lbs

We changed the bolt configuration - its butter smooth now and does not conflict with the magazine or cocking knob.
The cocking knob is *not* a production knob - it is a handle I borrowed from one of my other guns.
The cocking knob will most likely match the bolt handle and be closer to the gun.



The 1.25" CF shroud was slipped over the barrel and held in tension with another LDC I have.
The gap between the stock & forearm will be eliminated - we need to drill & tap the pump lever a bit farther back...each rifle will be fitted and marked before drilling and tapping from now on.



This is Jim...our metal master





Accuracy testing begins on Monday. I will test unsleeved, sleeved and sleeved/shroud tensioned.

The rifles *will* get a front band on both versions.

Pumping at 1800 psi is almost identical to a steroided 392 at 14 pumps.

Stay tuned!!!

Mike

[YEMX]

This rifle has come together well, I must say!!!!!  I can't wait to see more tuning data, and results of shipped rifles!!   

[CarsonRatSniper]

Trigger guards are on their way - accuracy testing is just with the barrel screwed into the breech = no bonded CF sleeve yet or front barrel band.
This is 5 shots @ 15 yards to get a baseline before cf sleeving.
These groups were shot without the LDC - the cf sleeve and LDC were just for a photo shoot.

I will also be developing Millennium specific slugs - the group dispersion of my slugs is clearly barrel harmonics.

Rifle was shot with a regged 1800 psi bottle attached via remote line.
The grids on the paper are 1/4".

Scope is a simple 4x Bug Buster and the bench was wobbly - we are building a concrete 50 yard shooting test range right now on Jim's property.

More to come in a few days...I'm finally shooting *Our* prototype!!! 

[Monkeydad1969]

Looking good.  So does this also mean that the valves are doing the job, and hopefully will be powering our rifles very soon? 

[CarsonRatSniper]

Jim is ordering more material and running 30 or 40 valves...you need to bear with us as I don't run the shop and we're doing everything we can finalizing the little details on these first 10 guns so we can ship them out...the valves are coming! Just have some patience please.

Mike

[Monkeydad1969]

Jim is ordering more material and running 30 or 40 valves...you need to bear with us as I don't run the shop and we're doing everything we can finalizing the little details on these first 10 guns so we can ship them out...the valves are coming! Just have some patience please.

Mike

I know it takes time.  I was just saying that in jest.

Joe

[c670809]

Looks like the same hole with the Kings.

Thanks for sharing the progress.

[Nomadic Pirate]

That gun looks really professional.

Will it have a barrel band ?

[Matt15]

Man, that looks COOL!!!!    I wish I could afford it but I can't right now.  Maybe in a couple years. 

[Matt15]

That gun looks really professional.

Will it have a barrel band ?

Manny it says right here:

Accuracy testing begins on Monday. I will test unsleeved, sleeved and sleeved/shroud tensioned.

The rifles *will* get a front band on both versions.

Pumping at 1800 psi is almost identical to a steroided 392 at 14 pumps.

Stay tuned!!!

Mike

[CarsonRatSniper]

Yes to the front band - we've extended the tube plug to accept one.
Its going to be really cool but you'll have to wait and see what we are doing with it

All aluminum is getting anodized black - I can't pay a $95 lot charge for parts on one or two rifles to get sealed clear. They'll look outstanding in black, I promise!!!

Running Kings @ 905 fps and 37gr Spitzers @ 775 fps takes 12 pumps per shot to top up to 1800 psi.

I will be posting large amounts of data over the next week - I would write it down if you're interested because I won't have time to answer repeat questions.

Mike

[CarsonRatSniper]

I'm going to be playing with carbide spring guide inserts inside the hammer - the goal is 905 fps with Kings with no preload and ? at max preload (intended for my slugs).
If you want to detune the gun to currently posted levels just remove the guide.



Mike