debouncer thoughts for the big bores

debouncer thoughts for the big bores

Joined: December 7th, 2008, 10:32 pm

March 18th, 2017, 12:46 am #1

Hello all,
I've done some browsing about various ideas for debouncers. But how about for the big bores? I have several Quackenbushes, from the 25 cal outlaw pistols (2) to the 50 cal Bandit and a 458 LA Outlaw. I love the DAQ's but they suck air like a Hoover on steroids. If I get 2-3 full power shots from my 9mm pistol I'm doing well. Even one more shot from a big bore while hunting could help.
Any thoughts?
Take care,
Evan in NC
Quote
Share

Joined: February 12th, 2017, 1:32 pm

March 18th, 2017, 1:40 am #2

Evan, Are you actually getting a bounce that you can hear? I have a .58 Quackenbush pistol that does not bounce at all. I wonder if it is because of the rather small transfer port of .225 inch? In any case, it shoots well and I get two shots about 530 FPS. without a detectable bounce.
Now, my own creation, the .58 Big John's Son, was getting a noticeable bounce. The gun is quite a bit shorter which means a shorter air tube. With a .312 transfer port, I got a bounce that you could hear but the exhaust valve would still close with about 800 PSI remaining. (from a 3500 PSI fill)
I finally got rid of all my bounce by increasing the preload on the hammer spring. Now it fully dumps with a 3500 PSI fill. No bounce and definitely more power. Velocity is 575 FPS with the 570 round ball. The drawback is, having to hold the hammer back a little bit as you start to fill the gun. I guess I was glad to get rid of the bounce, but like you, I wish there was another suggestion we could try. Hope my input helps some. John
Quote
Share

Joined: December 7th, 2008, 10:32 pm

March 18th, 2017, 3:25 am #3

I can't say I hear anything. But some time ago someone had a super slow motion video of a DAQ showing three distinctive discharges after a shot- a big one that propelled the bullet was followed by a smaller one followed by a third, smaller one. You could see the turbulence form each discharge. Perhaps the big bores "waste" a few debounce bursts of air that a debouncer could prevent.
Also, I saw the free-flight debouncer info but haven't time to closely examine it yet. I guess the hammer goes free from the spring before activating the valve. So there's no spring power to force the hammer to rebound against the valve after the initial strike?
Thanks for the response, would love to hear eveyone's input.
Take care,
Evan from NC
Quote
Share

Joined: December 11th, 2007, 4:23 pm

March 18th, 2017, 6:14 am #4

I don't remember if I posted it, but I did film a DAQ Bandit or LA 457 hammer bouncing in slow motion in 2009.. I agree that it bounced and off-gassed 3 times and this greatly increases the noise a PCP makes. I built a 2 part inertia striker that cured the bounce, but it also cut the power a bunch. I think some Theoben Rapid's had a similar striker? I think I sold the LA457 sized striker to Brent Schreiber with all my big bore guns about 4 years ago? I think there may have been a .308 design in the package also.

I drew several prototypes of a combination debouncer/ safety lever that I think would help big-bores in particular. I never hit on exactly the design I wanted because my Solidworks skills were weak, but picture a striker that has a recessed center so that it will rest flat on the valve body without touching the valve. When you pulll the striker handle back you rotate it forward and a cam or striker plate in the center of the handle rotates down to the level of the valve. After the trigger releases the striker the cam hits the valve once. The valve is pushed open until air pressure pushes it back. As the valve closes, it pushes the striker back.

Just after the valve face xonyaxts the seat and the striker moves away from it, the cocking handle/cam is rotated up by a spring or a weight that "teeter-totters" the cam or "safety gate" out of the way. When the striker spring arrests the striker and pushes it forward again the front of the striker hits the valve body (preferably with a rubber face) but it cannot hit the valve because the cam or gate is out of the way.

The safety feature is that the striker cannot touch the valve unless you deliberately rotate it forward until it clicks into position. The shooter could potentially have the bolt cocked in a hot hunting scenario but only rotate the cam forward when the grizzly starts actually climbing up his tree stand.

I've have an ink pen in my desk for years that has a triangle toggle visible through the clear plastic top. It sorta snags on a barb and rocks to the opposite side each time the button is pushed. One shelf is long and when the triangle tip rests on it it is rigid and holds the ball point out. When the tip flips to the short side the ink cartridge is pushed up insiide the pen. I've always thought it would be the perfect debouncer.

I'm in the process of downsizing, selling my maxhine shop and all but 2 of my airguns, but if someone is serious about colaberating on this debouncer idea I will see if my Solidworks 2011 version will let me retrieve these old models and maybe we can come up,wih something cool.



Last edited by rickpetersonms on March 18th, 2017, 6:19 am, edited 1 time in total.
Quote
Share

Joined: December 7th, 2008, 10:32 pm

March 18th, 2017, 1:59 pm #5

Rick,
Thanks for the info. The problem of course is that with the big bores one wants every bit of power you can get for the first shot as we use them for large game, and hopefully a second shot if we don't get the first one right. So the debouncer may take a little edge off that first shot to distribute it more evenly for the next shot or two, it may work ok.
If some experienced hunters would weigh in it would be valuable info.
Take care,
Evan from NC
Quote
Share

Joined: December 11th, 2007, 4:23 pm

March 18th, 2017, 2:37 pm #6

Evan, the 2-part Inertia-Striker did reduce power, but the design with a cam or "Safety Gate" that hits the valve one time and then retracts would not. When it is in position it hits the valve just as hard as a solid striker of the same weight would.
Think of a hole drilled into the center of the striker that is a little deeper than the distance the valve stem protrudes.
When the striker is pulled back and the cam or gate is clicked into position it essentially blocks this hole.

I'm assuming that the bullet is well past the muzzle and on its way before the heavy striker has time to bounce back and that all of the air that is exhausted in a non-debounced PCP after the initial release is wasted.

I think this is where we need Steve in NC or Mr. CO222 to bail us out with some math. Steeeeeeve, HELP!

Note- the "Safety-Gate" vision I have is similar to a revolver that has a little plate that gets between the hammer and the firing pin when the hammer is not at full cock. It prevents the hammer from striking the firing if the revolver is dropped. On this type of revolver, when the plate is in the way it stops the swinging hammer. If the hammer is fully cocked the hate drops out of the way.

In my "Safety/Debouncer" concept, the gate must be in the way in order for the striker to make contact with the valve. If the striker is released and the gate has not been rolled into position the base of the striker would bottom out on the valve body or the receiver. This would of-course require a stout design and another issue is that the striker hitting and no bullet being fired would probably be fairly loud and might scare game away.

A cure might be to have the cam or gate also prevent the striker from being released when it is in the "Safety" position, but then my Solidworks skills fall even farther behind. I can aaaaallllllmost picture a "teeter-totter" lever cut into the valve that would rock up into a notch in the breech when the striker is pulled back and would stop the striker from moving forward unless the striker handle is first ratated forward to lower it into the path of the valve. And I can almost, but not quite, envision a teeter-totter weighted and balanced so that when it is moving forward under full-cock spring pressure and traveling the full release length and time, would tip itself into position to be in the path of the valve, yet if moved forward with a weak rebound would remain up and out of the way. A design like this could be automatic, rather than require rotating the pull lever.

Oh, crap. I just found a dozen debouncer models and drawings from 2008-2010 and it looks like they still open in Solidworks. Now, if I can redeem my Photobucket skills, I suppose I'll have to post some pics.

Ah, this is why Airguns are a mental disorder
Last edited by rickpetersonms on March 18th, 2017, 3:23 pm, edited 1 time in total.
Quote
Share

Joined: October 11th, 2016, 2:27 pm

March 18th, 2017, 3:52 pm #7

Hello all,
I've done some browsing about various ideas for debouncers. But how about for the big bores? I have several Quackenbushes, from the 25 cal outlaw pistols (2) to the 50 cal Bandit and a 458 LA Outlaw. I love the DAQ's but they suck air like a Hoover on steroids. If I get 2-3 full power shots from my 9mm pistol I'm doing well. Even one more shot from a big bore while hunting could help.
Any thoughts?
Take care,
Evan in NC
pistols. They could have been turned into great carbines but I HATED the inconsistency and figured power is nothing when shots are dropping at 50 yards after the first sighted in one. If they got 22 useful shots from a .46-.51 lead ball out to 125 yards on 1800psi than what are we doing wrong? We have better projectiles that weigh less and should need less air. We have higher fill pressures more easily obtained. Not 1500 strokes to get 1800psi. Good God I'd rather have a Bow.
What we are doing wrong is number one being power hungry. I know States have mandated a minimum FPE and or caliber or combined but less is sometimes more. I would love a rifle that hits with 150 to 200FTLBS at 100 yards accurately but only if it got at least 10 consistent shots.
Do big Bores NEED to be big cast slugs? NO, they do NOT. They could make (and probably would if BB's were more standardized, which I'm seeing even out at .308,. 32, .40, .45, and .50) Big Bore lighter weight Diabolo pellets for less air consumption but long range shall we say medium power?
The Badger, and Corsair. Rifles I've considered but still shot count is too low for my liking. I don't need 400-600ftlbs for 2-4 shots. All I want is a rifle that is on par with a .22LR trajectory, BC, power, accuracy. That's everything I could ever hope for or want. WHAT should I be looking at or waiting for? Better heavier .22's or .25's? Bigger reservoirs on these air hogs? WHY no one has brought a double 500cc 4500psi carbon fiber big bore to market I have no idea. One in front, one in back like an Air force. Back tank for first high power shots and front tank regulated for more consistency and high shot count. This could work on everything from .177 (you could shoot for a week) to a .50 or those extreme like the 4 foot long barrel .72 that puts out over 1000FTLBS.
So, yeah, I'm interested in this thread. Improvements on Big Bore air consumption.
WHAT should I be looking at for 10-20 shots (or more) that can hit with (I'll compromise) 40-100FTLBS at 100 yards? Please, all advice is welcome. Can a big bore be DRAMATICALLY improved with a debouncer alone? I don't think it's the only engineering design needed. Can I get a Big Bore that can be restricted to hit with 40ftlbs at 100 yards and get 20 shots? Please, advise. Thank you











https://en.wikipedia.org/wiki/Girandoni_air_rifle
Quote
Share

Joined: December 11th, 2007, 4:23 pm

March 18th, 2017, 5:12 pm #8

Evan, the 2-part Inertia-Striker did reduce power, but the design with a cam or "Safety Gate" that hits the valve one time and then retracts would not. When it is in position it hits the valve just as hard as a solid striker of the same weight would.
Think of a hole drilled into the center of the striker that is a little deeper than the distance the valve stem protrudes.
When the striker is pulled back and the cam or gate is clicked into position it essentially blocks this hole.

I'm assuming that the bullet is well past the muzzle and on its way before the heavy striker has time to bounce back and that all of the air that is exhausted in a non-debounced PCP after the initial release is wasted.

I think this is where we need Steve in NC or Mr. CO222 to bail us out with some math. Steeeeeeve, HELP!

Note- the "Safety-Gate" vision I have is similar to a revolver that has a little plate that gets between the hammer and the firing pin when the hammer is not at full cock. It prevents the hammer from striking the firing if the revolver is dropped. On this type of revolver, when the plate is in the way it stops the swinging hammer. If the hammer is fully cocked the hate drops out of the way.

In my "Safety/Debouncer" concept, the gate must be in the way in order for the striker to make contact with the valve. If the striker is released and the gate has not been rolled into position the base of the striker would bottom out on the valve body or the receiver. This would of-course require a stout design and another issue is that the striker hitting and no bullet being fired would probably be fairly loud and might scare game away.

A cure might be to have the cam or gate also prevent the striker from being released when it is in the "Safety" position, but then my Solidworks skills fall even farther behind. I can aaaaallllllmost picture a "teeter-totter" lever cut into the valve that would rock up into a notch in the breech when the striker is pulled back and would stop the striker from moving forward unless the striker handle is first ratated forward to lower it into the path of the valve. And I can almost, but not quite, envision a teeter-totter weighted and balanced so that when it is moving forward under full-cock spring pressure and traveling the full release length and time, would tip itself into position to be in the path of the valve, yet if moved forward with a weak rebound would remain up and out of the way. A design like this could be automatic, rather than require rotating the pull lever.

Oh, crap. I just found a dozen debouncer models and drawings from 2008-2010 and it looks like they still open in Solidworks. Now, if I can redeem my Photobucket skills, I suppose I'll have to post some pics.

Ah, this is why Airguns are a mental disorder
Here are some of the De-bouncer models that I bounced-around a few years ago. All of them have one
or more deficiencies in concept, my Solidworks skills, production difficulties, or cost, but I think it would
be neat if someone wants to refine one of these designs for a big-bore in particular. I’ll briefly describe
these designs from memory.
On this design the shooter first pulls the striker back with a solid cocking lever. When he’s ready to
shoot, he rotates a knurled knob that sticks out of the back of the receiver like many power-adjusters
do. When rotated 180% it clicks into position with the half-moon now in the path of the valve stem.
Contact with the stem moves the half-moon plunger back just a hair to release it so that it can rotate to
the up position shortly after the striker moves rearward and breaks contact with the valve. All I can find
is a PDF of this design so I don’t remember if I ever modeled the release mechanism or not.


This one has a cocking lever on one side and a Safety/power-level/debouncer lever on the other. Once
the striker is pulled back the second lever is lifted into one of
3 power positions. Power is determined by how deep the hole in the disk is that the valve stem contacts.
After hitting the valve the disk is pushed back a hair so that it is tripped and it then rotates out of the
way after the striker is pushed backward and breaks contact with the stem. The disk is now in a position
where a through-hole aligns with the valve so it will not push the valve open.


This one has a ratchet that holds a plunger in place the first time the striker moves forward. The plunger
pushes on the valve with full force, then the ratchet drops down so that when the striker comes
forward again the valve stem can push the plunger back into the mainspring a bit. This would lessen the
slamming of the striker as it bottoms into the receiver. I don’t remember if I ever drew that trip
mechanism for the ratchet.

Hmm. It looks like this one is a modified version of the one above with an attempt at a trip
mechanism.
On this one it looks like the cocking lever gets pushed in to block the valve path and then pops out after
it breaks contact with the valve stem and heads backward.


I think the little rocker below the striker was spring loaded and supposed to snag the striker before it hit
the valve a 2nd time.


It looks like this red plate locks the plunger in place when it is pushed down.


Here is the ink pen that I’ve somehow managed to no lose for years. It says Slide Systems Inc 1418 40th Street
somewhere in California. It just dawned on me, after a decade, that I should have Googled this company
to see if this mechanism is what they use in their SLIDE SYSTEMS and if they could help with a
debouncer. What a dummy for never checking 
Note that when the triangular toggle is tipped LEFT the ink cartridge is retracted.
When it is tipped RIGHT it holds the cartridge firmly out. The triangle has a round rim at the bottom (like
a witches hat) that snags on a short barb on one side and a long barb on the other. This causes it to tip
alternate directions and change how far it lets the cartridge move.



This one has a side release. The release could pass forward over a ratchet as the striker carries the locked-in plunger to the valve. After the valve pushes the plunger/striker back the ratchet could release the trip so that the plunger is no longer held solidly.


OK, time to STEP AWAY FROM THE COMPUTER, Richard...............................

Last edited by rickpetersonms on March 18th, 2017, 5:41 pm, edited 1 time in total.
Quote
Share

Joined: March 9th, 2013, 1:47 pm

March 18th, 2017, 7:19 pm #9

Hello all,
I've done some browsing about various ideas for debouncers. But how about for the big bores? I have several Quackenbushes, from the 25 cal outlaw pistols (2) to the 50 cal Bandit and a 458 LA Outlaw. I love the DAQ's but they suck air like a Hoover on steroids. If I get 2-3 full power shots from my 9mm pistol I'm doing well. Even one more shot from a big bore while hunting could help.
Any thoughts?
Take care,
Evan in NC
Expecting more than 2-3 shots is not going to be improved by a de bouncer.
I excepted this fact, and just tether to a 3k output 90ci CF tank. Good for around 35 full power shots



As a carbine, this .58 Outlaw is exceptionally accurate, it's alot of fun to shoot.
Quote
Share

Joined: December 7th, 2008, 10:32 pm

March 19th, 2017, 4:01 am #10

Pretty awesome set up. That will work ok in some scenarios but for deer hunting I don't want to tether. Dennis rates his 458 LA at 500 ft lbs with a heavy 400+ gr slug. Guys have shot clean through Bison at the ribs with his 458's. My 458 will shoot a 457 rb at 970 fps for 300 fpe. Lots of guys have used 909's at around 200 ft lbs with good results. Maybe a heavy slug at 250-300 fpe would work well, and maybe a good debouncer will help get me there with a couple more rounds. Let's see what the tuners can come up with. Knowing your range and proper placement, of course, are critical.
Take care, Evan from NC
Quote
Share