EDgun Leshiy2 "dwell time" tuning?

[Stubbers]

I am just bouncing with my ideas.
The Dwell tuning is seasonal in my mind, one low power for winter time in a basement fun with lightweight pellets, and one for summer outdoors at the gun range with high speed heavy pellets.
Missing a second dedicated Reg for indexing mechanism to work with both lightweight and heavy duty pellets - in my eyes is a collateral damage

Gotcha, that should clear the air a lot here. I hope what I said above makes sense with how increasing the 2mm screw orifice is no different than reducing your puck orifice, the latter being options available directly from Ed.

I would agree on your sentiment entirely regarding the 2nd reg. What you're trying to achieve is increased pressure available at the indexing mechanism which a smaller puck provides just the same as an increased 2mm screw orifice.

It's paramount that in lower power tunes you reduce the puck size for a reason, and not just increase jet size. GL

-Matt

 

[bigHUN]

The .22 mag backplate holes orifice size is 4.9 mm.
Reducing a puck orifice size below that diameter can make the only difference, I will try that first printing couple in 4.5 - 4.0 - 3.5 - 3.0.
Btw, what is a function for the item #13 in the forward plug diagram, I don't have that part in mine?
Also, the 2mm hole at 3 a clock is not "feeding" the indexing but "venting" it. The 6 a clock hole feeds it, also the cut through in center.

 

[bigHUN]

... trigger/valve disconnector ...
... orifice reduction piece ...
...disconnect piston spring ...

Sergey, can you please redo one more time with # numbers from diagram? We using learned language and I am getting confused

 

[Stubbers]

The .22 mag backplate holes orifice size is 4.9 mm.
Reducing a puck orifice size below that diameter can make the only difference, I will try that first printing couple in 4.5 - 4.0 - 3.5 - 3.0.
Btw, what is a function for the item #13 in the forward plug diagram, I don't have that part in mine?
Also, the 2mm hole at 3 a clock is not "feeding" the indexing but "venting" it. The 6 a clock hole feeds it, also the cut through in center.

Ah makes sense, I thought the 2mm screw orifice being drilled open was going to feed more air through, same premise as the reduction of the vent size as @Sergey1972 suggests accomplishes the same thing, more pressure available at the indexing mechanism. Certainly can see it being a fix, but again for low power tunes as you're after, a smaller puck is highly recommended.

-Matt

 

[Sergey1972]

Piston that moves trigger pin to the left (trigger disconnector piston don't know proper name, would love a proper pdf of the parts diagram)
2mm screw actually reduces flow in the 3 o'clock hole. Screw or simple bushing accomplishes same thing - reduce orfice.
Too much air is wasteful and in my case may give the magazine cycling piston too much speed causing it to skip (my guess for my particular gun).
Puck hole being smaller is a legitimate way to improve ES. Can't remember what mine is for .22.
Using puck to reduce a lot of power, puts undue stress on the hinge locking mechanism (think of puck as acting as piston trying to open the folding system).

 

[bigHUN]

What is the function of #13?
Look to me something to limit either a space or travel?

 

[bigHUN]

cycling piston too much speed causing it to skip (my guess for my particular gun)

As you said in your way interpreting in English, I almost said it this way "the indexing made to the mag jump faster = earlier and the heavier pellet didn't had enough time transferring from mag into breach resulted jamming it"
Would this be correct somehow?
I am speculating only, but if I would put a piece of full length tube below inside setscrew #34 how much that could slow the flow? In a same way as the 2mm sets crew inserting into the 3 a clock hole to slow the venting?

 

[Sergey1972]

View attachment 401128
What is the function of #13?
Look to me something to limit either a space or travel?

Haven't gotten to this one yet. Closes of volume that is filled when main valve opens. This volume softens the burst of air as far as I can tell. Great place to mount sensor to graph the firing pulsewave. Reducing volume will change dwell time and be rougher on the pellet ( increased firing chamber pressure)

 

[Jack.K]

Ed did a video of the internal differences in the forwarding plug version. Not sure if this applies to the dwell time tuning.

 

[Stubbers]

#13 is basically similar to what I was suggesting in earlier posts (too lazy to go back) about altering the volume to reduce dwell...heh. Anyways...Jet sizing isn't the ONLY way to reduce dwell as others have mentioned. You can increase volume in one location or reduce it in another to reduce dwell.

-Matt

 

[bigHUN]

I

Haven't gotten to this one yet... reducing volume will change dwell time and be rougher on the pellet ( increased firing chamber pressure)

II will put a thread in the hole at 3 a clock, also will make a piece of tube for that hole what the #34 plugs. I want to see which works better.
Don't care at the moment how much rough on pellet until inside rifling, I just hoping to minimize that pulse at the muzzle.
But I need to fix my YH first stage piston first, because these testings will need a lot of degassing.

 

[Sergey1972]

Ed did a video of the internal differences in the forwarding plug version. Not sure if this applies to the dwell time tuning.

Power is affected by dwell time and firing chamber volume. The new model front plug has a little less firing chamber volume due to a lack of internal groove. Tolerance stack up of bore for jets and length of Jet valve tip can affect protrusion and main valve travel time. This would explain the difference in velocity between 2 otherwise identical guns. Sanding the tip of the valve pin in the jet will increase dwell time but if you overdo it, you'll need to buy a new valve pin.
Also, he mentioned that the 2mm (3 o'clock hole) we've been discussing is now 1.5 mm in newer Front Plug bodies.

I'll check both of mine before I restrict the size. One of them is completely reliable and one has indexing issues at mid-pressure. Once I see which one is bigger I'll know what to do. Maybe it's the 1.5 I need to increase to 2mm ..... who knows?

 

[Stubbers]

Power is affected by dwell time and firing chamber volume. The new model front plug has a little less firing chamber volume due to a lack of internal groove. Tolerance stack up of bore for jets and length of Jet valve tip can affect protrusion and main valve travel time. This would explain the difference in velocity between 2 otherwise identical guns. Sanding the tip of the valve pin in the jet will increase dwell time but if you overdo it, you'll need to buy a new valve pin.
Also, he mentioned that the 2mm (3 o'clock hole) we've been discussing is now 1.5 mm in newer Front Plug bodies.

I'll check both of mine before I restrict the size. One of them is completely reliable and one has indexing issues at mid-pressure. Once I see which one is bigger I'll know what to do. Maybe it's the 1.5 I need to increase to 2mm ..... who knows?

Alternatively extending the jet valve tip with a custom made one if there is clearance between it and main piston can reduce dwell time, or adding / affixing a tiny spacer on the main piston as I mentioned earlier as this will also reduce the volume minimally in that chamber that the check valve/jets feed, two birds one stone..but it would have to be a custom made spacer that leaves the original delrin balls seal unscathed and possibly require other clearances, only applicable if say there is .02"-.025" clearance or so, and you take it down by either method to .01" or even .005", so the jets are opening sooner. Heck you could even have the check valve/jet pre-activated by .005-.01".


My pilot valve's check valve tip that I made touches my main piston at rest.

Got to love skinning cats 6 ways to Sunday.

-Matt

 

[bigHUN]

... I'll check both of mine before I restrict the size. One of them is completely reliable and one has indexing issues at mid-pressure. ...

My Leshiy2 Serial Number: 4093
Purchased Aug.2021 that makes me calculate the built date minus 3 months including freight.
The 2.05 mm hole was drilled first and pocket milled afterward, resulting a slightly oval hole in bottom corner.
Only way to convert 2mm into 1.5mm is oversizing the setscrew to 4mm and drill that with a 1.5mm for venting.
I don't think restricting the "feeding" with other parts could be done better because the indexing is already ported way to open. Either plug the hole @6 or insert a tube below the #34. Depend which one is feasible at home workbench.

 

[Sergey1972]

My Leshiy2 Serial Number: 4093
Purchased Aug.2021 that makes me calculate the built date minus 3 months including freight.
The 2.05 mm hole was drilled first and pocket milled afterward, resulting a slightly oval hole in bottom corner.
Only way to convert 2mm into 1.5mm is oversizing the setscrew to 4mm and drill that with a 1.5mm for venting.
I don't think restricting the "feeding" with other parts could be done better because the indexing is already ported way to open. Either plug the hole @6 or insert a tube below the #34. Depend which one is feasible at home workbench.

View attachment 401293

The 6 oclock hole you have circled is for bleeding the gun. The 3 oclock hole is the one that was reduced.

 

[bigHUN]

The 6 oclock hole you have circled is for bleeding the gun. The 3 oclock hole is the one that was reduced.

I didn't wanted to open the Forward Plug to check with a pin, but looks like me better measure and make it in a CAD file. Thanks for a warning.

 

[bigHUN]

...in my case may give the magazine cycling piston too much speed causing it to skip...

There is always a way to slow down the magazine advancing speed with the #12 screw, but I never wanted to wear the mag shaft that way.

 

[Sergey1972]

There is always a way to slow down the magazine advancing speed with the #12 screw, but I never wanted to wear the mag shaft that way.

View attachment 401454

DId that got it working, when I first received it. Heavy pellets no issues. .22 Hades 90-110 bar doesn't cycle well, above and surprisingly below cycles fine. Plastic mags are lighter and cycle worse.

 

[bigHUN]

DId that got it working, when I first received it. Heavy pellets no issues. .22 Hades 90-110 bar doesn't cycle well, above and surprisingly below cycles fine. Plastic mags are lighter and cycle worse.

Asked Brian today about the 2mm hole and he advised to try the #12 first (back in time I didn't wanted to do that mine screw is all the way out).
My version L2 has about a same issue as your with indexing with jets bigger then 0.7+0.7, smaller working fine.
Back in time I had the gauge mounted and if I can recall the issue was somewhere 140 bars and higher on the Reg and the mag was pinching the heavy 25gn MRD's.
My attention was always toward using bigger jets possible to shorten the Dwell for target shooting. Up to 50 meters with MRD's it was MOA, but for longer distances I needed more power this where the air blast started kicking the pallet skirts and the accuracy broke.
I don't shoot slugs with L2 I did not needed plastic mags.

 

[Sergey1972]

Asked Brian today about the 2mm hole and he advised to try the #12 first (back in time I didn't wanted to do that mine screw is all the way out).
My version L2 has about a same issue as your with indexing with jets bigger then 0.7+0.7, smaller working fine.
Back in time I had the gauge mounted and if I can recall the issue was somewhere 140 bars and higher on the Reg and the mag was pinching the heavy 25gn MRD's.
My attention was always toward using bigger jets possible to shorten the Dwell for target shooting. Up to 50 meters with MRD's it was MOA, but for longer distances I needed more power this where the air blast started kicking the pallet skirts and the accuracy broke.
I don't shoot slugs with L2 I did not needed plastic mags.

My plastic mags are just the new black mags. Nothing having to do with slugs. I think the new mags are all Delrin (except the 9mm). I have red and black aluminum mags and bunch of black plastic mags in .22.