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Adjustable Extended Probe

Started by quickster47 †, April 05, 2016, 11:49:28 PM

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quickster47 †

Quote from: CraigH on April 06, 2016, 10:30:27 PM
Carl,

Is the sleeve a stop setting device?  I was trying to imagine an ability to have a quick retraction and be adjustable in the same device.     :)

Looking forward to the next installment on this mod.   :-*

Yes and no.  As it turned out the longest 2-56 screws I had were just barely long enough by them-self to extend out the bolt by maybe a 1/4" but for my purpose that was a little bit short.  So I used a second screw and joined them with the sleeve.  It also worked out that it served as a stop setting device.

More to come...

Carl

I've never wanted something so useless in my life.
In Omnia Paratus
1947-05-19 - 2016-07-14 †

quickster47 †

Because I'm no longer using the conventional bolt to cock the gun I did have to change the cocking mechanism because of the adjusting rod. I made up my own rear cocking parts and must say I really like what I've created. Very easy to cock the gun. I am working on another cocking handle but for now this one works very well, just looks plain Jane.  I also am getting a heavier hammer as the one I made is Delrin and while it does work, it's a little bit light and takes at least three tries to pierce a Powerlet.

Carl

I've never wanted something so useless in my life.
In Omnia Paratus
1947-05-19 - 2016-07-14 †

CraigH

VERY attractive and a bit retro - like earlier Crosmans.   8)     I like it!    :-*

I have spent a few hours looking at a bolt and making crude hand drawings (need to get some rudimentary generic cad capability), and I think I understand what I was trying to say.    ???   Now I have a possible concept formed from the former imagined thing.  Hopefully can get a better plan for the rear of the breech - I'm thinking changing the lever idea to something like the ball-check bolt hold-open you posted a short time ago, but on an additional part, not the bolt.

And .... I knew there was a reason for the cocking change, but the light bulb only just became bright enough .... the hammer pin. Semi- :-[
Craig
Lone Tree, Colorado

With freedom comes a terrible responsibility

oldgearhead

#18
Carl -Did you need to modify the cocking pin? Or are you using the older model?
Wow! You posted that at the same time I asked the question.
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quickster47 †

#19
Quote from: CraigH on April 07, 2016, 12:40:01 AM
And .... I knew there was a reason for the cocking change, but the light bulb only just became bright enough .... the hammer pin. Semi- :-[

QuoteCarl - Did you need to modify the cocking pin? Or are you using the older model?

The old cocking method has several drawbacks.  1) Because there is no guide pin you can only use the old style breech, breech screw in the front position, because without the guide pin the hammer can rotate.  If you try and use a new style breech, breech screw in the rear location, the screw will go into the hammer and even if you notch the hammer, because there is no guide pin it can rotate and end up jamming into the rear mounted breech screw.  2) It is now a two step process to shoot the gun, you must load a pellet and then cock the gun or visa-versa.  Probably a couple more items I'm missing.

So what I'm doing now does not use the hammer guide pin and that makes for some interesting changes needed.

In this day and time it makes more sense to do it the way Crosman now does.

Carl

I've never wanted something so useless in my life.
In Omnia Paratus
1947-05-19 - 2016-07-14 †

WyoMan

Kudos  :-* from what I've read, no one has done a full-depth experiment with seating distance (on airguns)...and this has been discussed for at least decade. The only consensus I'm aware of is that seating the pellet beyond the transfer port is necessary.

One thing I've noticed with some unscientific probe chances...the degree of pellet engraving can change with the seating depth (depending on how the lead-in was cut)....i.e tight fitting hard antimony-lead pellets will benefit more from full engraving.

There are some other variables at play. Don't feel like you need to rush it for us...although I for one am very curious. Nice probe design, btw  :-*
Wyo
Welcome to your life :)
Member of the Western Heretic Alliance

CraigH

A Concept Not Yet Mature      (Since I brought this up and without pictures didn't happen, here is the thing, flawed as it is.    :)  :(    :)  )

What I was thinking (perhaps should be, What was I thinking?!!) is an ability to retract the probe, from whatever point it is adjusted to, by pulling back on the rear of the probe which runs through the entire assemblage.  First image is the parts, second is the rear of the bolt, showing thread and the beginning of the 1/8" I.D. diameter section.

The parts,left to right, are:      (the 2-56 machine screw which runs through all this not shown as it is not available)

1. Bolt, starting at its back - 10-32 I.D. thread 3/8" deep for cap to retain adjuster and spring
                                       - 1/8" diameter section for another 1 1/8" which contains the adjuster and spring
                                       - The remainder drilled 0.086  (#44) through the front of the bolt
                                       - Radial hole to pin adjuster sleeve  (There is no handle hole drilled in this bolt)

2. Adjuster Sleeve - O.D. ~ 0.120-0.0122 - I.D. tap 2-56 through

3. Spring - The spring shown is too small - and even if nominally correct, this is where problems develop.

4. Cap (not finished) - O.D. 10-32 thread x 3/8" long - I.D drill 0.086 (#44) - Could be longer and actually should be.

5. Sleeve for Ball Check - 3/8" long - O.D. 1/4" - I.D. tap 2-56 through - Radial hole for ball check.

Additional - drill a series of shallow holes in the interior wall at the rear of the breech.

Ok, a few of probably many issues; since pellets can hang up either on the tiny breech bolt or entering the barrel (especially .177s), the spring has to be pretty heavy, more than any spring that would fit the space.  There is no method of keeping the ball-check sleeve from rotating; an axial groove through the shallow holes in the breech might do that.

Definitely small return for the amount of work and parts (which when NOT added don't break  :D ).  There is not much space in the bolt for all this - Need a fatter bolt, larger I.D. breech.  I think I can live with a few less fps.   :)    Enjoy but don't fall out of your chain loling!
Craig
Lone Tree, Colorado

With freedom comes a terrible responsibility

quickster47 †

Well that is definitely some good food for thought.  And one thing you certainly have correct is that the whole thing is going to be small and can be somewhat fragile.

Building one or maybe even two can probably be done but for a mass market I don't think it is very feasible. However, time will tell.

Thanks much for your input Craig and keep thinking and coming up with ideas.  :-* :-* :-*  That's how we keep advancing.

Carl

I'm also stuck right now cause I don't have a sacrificial aluminum, or steel, breech to use for some of my needed modifications.

I've never wanted something so useless in my life.
In Omnia Paratus
1947-05-19 - 2016-07-14 †

Crosshairs

Saw this on Facebook Carl and as always another great idea.
        Mike
Treat people the way you want to be treated, Life will be so much better !!!

Gippeto

Agreed. :)

Slick idea and nicely executed. Look forward to the results. :-*

Al

JP_Quebec

HI very nice  work,
if I may suggest a little something,how about getting rid of the threads  and making it much smaller at the end to push the shot in ?

Just a suggestion

JP

quickster47 †

Quote from: JP_Quebec on April 14, 2016, 07:57:51 PM
HI very nice  work,
if I may suggest a little something,how about getting rid of the threads  and making it much smaller at the end to push the shot in ?

Just a suggestion

JP

A very good suggestion and one that makes sense.  So, I have made a couple of the extended probes now and one of them is threadless, has no threads on the end that will push the pellet.

Will take a picture of it later and post it so others can see what it looks like.

Testing will be interesting to say the least.  Not sure it will make a bit of difference but we shall see.

Carl

I've never wanted something so useless in my life.
In Omnia Paratus
1947-05-19 - 2016-07-14 †

droid

Once again Mr Carl shows he is the master of probes.

I must admit though I tend to use standard length probes as I prefer more loading room.

So I want a probe pin that retracts when I pull back and protrudes when I push forward.

So come on Carl get your nano machining going
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quickster47 †

Quote from: droid on April 16, 2016, 01:33:00 PM
So I want a probe pin that retracts when I pull back and protrudes when I push forward.

So come on Carl get your nano machining going

I've never wanted something so useless in my life.
In Omnia Paratus
1947-05-19 - 2016-07-14 †

quickster47 †

Worked on a couple more extended probes and messed around with ideas to make the thing somehow retractable.

There just ain't much room in a 1/4" bolt to allow for some of my ideas.  Sigh...

Carl

Still waiting on a donor breech so I can start messing around with this some more.

I've never wanted something so useless in my life.
In Omnia Paratus
1947-05-19 - 2016-07-14 †