Tuning A Tail of Two Lelya - Really - Really odd

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nugria

nugria

Member
Sep 7, 2019
169
5
Florida, United States
Hi All,

I'm pretty sure I need a reg tester. Currently I've a reg tester on the way. My Chrono was down. I did get a chrono back on-line. I've two Lelya and one is acting very weird. The weird one (call it #2) is new to me and arrived with a Huma Power regulator installed and the Edgun reg in the box.

Both Lelya are shooting 14.3gr Crossman hp right now for these tests. 

Lelya #1 I bought new. Later model, plastic trigger, plastic rollers, die-cast sled. It is not molested except the hst backed all the way down. It acts as expected. When on regulator it is shooting around 385 fps. As it rolls off regulator the velocity increases starting at 125 bar to 70 bar maxing out at about 622 fps at 70 bar. Pretty much what I'd expect. Likely a 125 bar reg pressure.

Lelya#2 Purchased used. Early model. Steel trigger, CNC sled, ball-bearings for rollers. It doesn't act as expected. I've assumed that the Edgun regulator was set to 125 bar. I have re-installed the Edgun regulator and removed the Huma Power regulator. Well? When the reservoir is above 125 bar, hst backed all the way out it is shooting at 790 fps! Yup. Shooting down the pressure it just starts loosing velocity below about 115 bar w/o a spike. Normally this is a sign of excessive HST for the regulated pressure from my limited understanding. The gun is much louder than Lelya #1. Maybe it should at about 2x the velocity. 

I examined both hammer springs (in place). Same number of coils visible, same gap when not cocked (there is no preload on the hammer spring w/o cocking the hammer and about 0.05" of "slop" fore & aft motion on both guns). I've had the valve out of Lelya #2. Looks good. Measures up per drawings I've found for stem length and such. I've not compared the spring that closes the valve as I really didn't want to open up the unmolested Lelya I purchased new.

Ok. Please throw the rocks at me underhand. Somehow I think I'm going to get pummeled. What makes me scratch my head is if the reg pressure is so low that the backed off hst is excessive, would it still be shooting near 800 fps?

This is why I decided to get a reg tester.

Thanks,

Nugria
 
Typical valve action:

Pressure too high = valve lock = low velocity

Pressure good = expected velocity

Pressure a little lower = valve ooens wider stays open longer similar velocity.

Pressure very low = valve opening wider and staying open longer cant compensate low pressure and velocity tapers down.

Maybe the original regulator isn't working and was replaced with Huma?

Maybe you are operating leyla 1 near valve lock and velocity goes up as pressure goes down.

Food for thought. It's 1am and Im rambling.

Good luck. 
 
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Hi Sergey1972,

Lelya #1 is certainly near valve lock. As #1 is shot down below the reg pressure the velocity increases quite a bit. I'm just somewhat surprised at Lelya #2 not being even close to valve lock with the same hammer spring setting. #2 has been shot quite a bit more than #1. Break-in?

From the chrono data I can see when each of the guns reservoir pressure drops below the regulator set-point. #1 increases in velocity. #2 rolls off in velocity.

Nugria
 
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Hi All,

I agree. 70b would be a good reg setting for Lelya#1 at this power level. I may do that as an Edgun regulator tester is in the works.

Dropped a Huma 12fpe set-up into Lelya#2 last night. Based on some info from the UK for the kit in an R5M Matador Std., set the reg @ 61 bar per the Huma tester and swapped out the factory hammer and valve springs for the Huma parts. (BTW, ordered the Huma kit from Huma on Thursday and had it on Monday. Buy lots of stuff as the shipping is 30 euro. Would have purchased it in the US but seems to be out of stock in the states.)

As expected with the Huma kit, the reservoir is now larger, the plenum is smaller, the shot count on the initial settings is decent. (I'll run the efficiency numbers when I get the chrono out.) The reservoir is currently dropping .73bar/shot. That is roughly 200 shots on a 200 bar fill. I'll get the chrono out on it this weekend. Might have to dial things up a bit as I'm thinking it is shooting at about 6 fpe right now :) 8-12 fpe is my goal. It is quiet. Maybe not HW100 12fpe quiet, but backyard friendly. Mechanical noise on firing is way down also which is good for my right ear. I'm going to leave it cocked for the rest of the week to "age" the hammer spring a bit. Some somewhat useful information below:

Springs removed from Lelya#2:

Hammer spring - 0.255OD, .057 wire, 24.5 coils, 2.324 free length

Valve spring - 0.299OD, 0.056 wire, 11 coils, 1.22 free length

Huma springs installed in Lelya#2 (note valve spring has a shorter pre-load length in the Huma design:

Hammer spring - .0.274OD, 0.056 wire, 28.5 coils, 2.28 free length

Valve spring - 0.280 OD., 0.040 wire, 11.5 coils, 0.99 free length

Enjoy,

Nugria

ps. Couldn't resist. Took it out for a moment to the chrono. Consistent 585 fps, about 8.8 fpe. Only ran 10 shots. Later to see how it settles-in and where I am with HST.
 
Upvote 0
Sergey1972,

I did examine the valve, valve stem, but didn't pull the barrel to check the porting on Lelya #2. From below everything looked stock with no signs of activity. 

I hate to tear down Lelya #1 as it is essentially new and will put 9 pellets in one ragged hole at 30 yards (easy for most, quiet an accomplishment for me shooting 14.3gr Crossman HP). I realize that Lelya #1 is in a less than desirable state of tune with low hst and high regulator pressure but it seems to shoot my shorter distances well.

With all said, I've posted the spring dimensions of the springs I removed from Lelya #2. Has anyone measured their springs while in their guns? Just wondering if those are factory springs.

Thanks,

Nugria
 
Upvote 0
Hi All,

Finally got a regulator tester for the Edgun regulator. Turns out for about $140 delivered you can get one of the old style regulator testers for the old Edguns. While it will not work with the new style regulators, if you add a 0.538" thick spacer on the regulated side and put face seal o-rings on the faces of the spacer, it is good to go. On the tester side you need an OD on the o-ring of .75 or better (as the inside of the tester has a bump) and on the regulator side it just needs to be about .50" or better OD. Here is a picture of the spacer I used. It worked the first time. My "mechanical guess" based on measurements and turns of the adjuster was only 10 bar from my desired set-point.
CIMG1926.1636569838.JPG


Enjoy,

Nugria
 
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