Low friction linear slide for springer

Low friction linear slide for springer

Joined: September 25th, 2006, 2:19 pm

April 7th, 2012, 2:52 pm #1

Thinking about trying this. Its only an outer tube where coil springs are used for the low friction and hopefully zero clearance linear motion between the outer tube and the springer action. Note that the scope will not travel with the piston recoil.

I desire to have the sliding friction distributed entirly around the compression tube although it will be impossible to completely eliminate friction.

Spring bearings are nothing more than springs from a common cig lighter held in position by a wire loop as shown

Before installing the compression tube into the outer tube, the entire springer action, including trigger group. will be spun ballanced to ensure that all the mass will be equally distributed around the centerline of the spring piston. This is to insure a "straight backward" path of the recoil hopefully reducing angular momentum thereby hold sensitivity.

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Joined: November 28th, 2002, 6:26 pm

April 7th, 2012, 3:13 pm #2

...and aiming for inclined (i.e., uphill or downhill) shots - that is to say, when there are substantial longitudinal forces?

Steve
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Joined: September 25th, 2006, 2:19 pm

April 7th, 2012, 4:02 pm #3

Although every effort must be taken to ensure free movement of the action within the outer tube.

To be honest, I havent nailed anything down yet on both accounts.
The outer tube will have to be slotted to clear the trigger group. Perhaps the slot might offer a means to eliminate rotive movment sorta like a K-way.

Keeping the action in the forward position with the least amount of force to be overcome before backward movement will be tricky. I actually entertained magnets but there should be a better way. However anything mechanical attached to the action would have to be included in the spin ballance procedure.

I believe cocking could be managed while the action was arbitrarily completely forward or completely rearward in the outer tube. I'm thinking that the directional forces of cocking would throw the action to the rear so a slight tug on the barrel after closing would be needed to lock the barrel, under minimal tension, in the forward firing position.

Any ideas?
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Joined: April 12th, 2002, 5:26 am

April 7th, 2012, 5:21 pm #4

Thinking about trying this. Its only an outer tube where coil springs are used for the low friction and hopefully zero clearance linear motion between the outer tube and the springer action. Note that the scope will not travel with the piston recoil.

I desire to have the sliding friction distributed entirly around the compression tube although it will be impossible to completely eliminate friction.

Spring bearings are nothing more than springs from a common cig lighter held in position by a wire loop as shown

Before installing the compression tube into the outer tube, the entire springer action, including trigger group. will be spun ballanced to ensure that all the mass will be equally distributed around the centerline of the spring piston. This is to insure a "straight backward" path of the recoil hopefully reducing angular momentum thereby hold sensitivity.

rolled back in itself in the clearance between inner and outer tubes. I shot a springer set up this way, and it was essentially reconciles. Also very quiet and vibration free.
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Joined: September 25th, 2006, 2:19 pm

April 7th, 2012, 6:27 pm #5

Good idea. I was concerned how the rolling spring bearing would handle dirt.

The gun will be a mid-power Beeman Grizzly (2 barrels).

What would you guess the travel should be allowed for the recoil? One inch too much??
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Joined: November 28th, 2002, 6:26 pm

April 7th, 2012, 7:04 pm #6

...R = S x (Pw + Sw / 2) / (Aw + Sw / 2)

where...

R = recoil distance
S = piston stroke
Pw = piston weight
Sw = spring weight
Aw = action weight not including piston or spring


Steve
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Joined: September 25th, 2006, 2:19 pm

April 7th, 2012, 8:20 pm #7

Thanks, Steve nt
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Joined: November 28th, 2002, 6:26 pm

April 7th, 2012, 9:43 pm #8

It's just the idea that, because the 1st Law of Motion requires the center of mass of the springer system to stay stationary while the mass of the piston moves forward, the rest of the springer has to move backward just enough to balance it, with the motion required being given by the ratio of masses times the piston's stroke.

Steve
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Joined: September 25th, 2006, 2:19 pm

April 7th, 2012, 11:05 pm #9

Will there be a vector quantity involved regarding recoil distance when shooting "uphill"?

PS edit
Some how I thought gravity would effect the action shooting up at a steep angle. But forget the spring and piston would also be counteracting. So recoil should not then be effected.
Last edited by oo7fuzz on April 8th, 2012, 11:13 pm, edited 1 time in total.
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