LGV Master Ultra .22 cal baseline chronoing

[Toxylon]

Some may remember I bought a nice LGV Master Ultra .22 cal a while back. I also got me a Medina Custom 23 J guide set for the Walther, still waiting assembly. My airgunning advances at a glacial pace these days, but every little bit helps.

So far I've broken the LGV in for some 250 shots. Still got a ways to go, but since I'm planning to switch her innards, I wanted to get a baseline chrono session done at this point.

With the weather finally co-operating, I rigged up my chrono in the backyard. The LGV is the only gun I have that I can chrono this way, since it can be fitted with a silencer. So, I screwed on a Decimeater to cut down the noise. People often say silencers don't do much with springers, but my LGV goes from a echoy bark to a dull "plat" with the Decimeater, making stuff like backyard chronoing a reality.

I chronoed Exacts, FTT 5.53's and Superdomes, shooting 10 pellets per make. The LGV shoots very consistent velocities (+/- a couple of fps) within a pellet type. The following figures are 10-shot averages:

Walther LGV Master Ultra .22 cal (2018), fully OEM, after 250 shots:

Exact 1.03 g

609 FPS / 13.1 FPE

FTT 5.53 0.95 g

629 FPS / 12.7 FPE

Superdome 0.94 g

642 FPS / 13.2 FPE

Surprisingly hot figures, considering this is the 12 fpe / 16 J version. A Brit would be in legal trouble with those kinds of stats.

Exacts being the slowest, and Superdomes being the fastest, matches every .22 cal springer I've tested. However, the velocity difference between those two with the LGV is only one half of what my HW95L does, with close to a 70 fps difference with the HW. As is evident with the FPE figures above, with the LGV the velocity difference is explained by the higher mass of the Exacts.

I expect the Exacts to be the most accurate pellet for my Walther, but that remains to be seen. Just recently I bought a PelletGage to see what my tins of .22 cal pellets actually contain. Hope to get spectacular accuracy out of this lovely air rifle.

[Yogi]

Hope you enjoy it!

I was bummed when they were cancelled...

Love to know if Hector's "hot spring" boosts power + 100 FPS?

May we assume that at 12 fpe, it shoots dead calm?

-Y

[MartyMcFly]

Duke, are you planning to open up the TP on your LGV or will this just be guide and spring work? Just curious as I have an LGV too - love it except the trigger, which I’m experimenting with first on my LGU before touching the LGV.

-Marty

[Toxylon]

Thanks, Yogi

I go by Hector's account of up to 16.9 fpe after this mod. Haven't calculated the fps, but you go ahead 

My LGV at present is the smoothest springer I have (small wonder). Would I call it dead calm? Pretty close.

Marty,

I will only perform reversible mods on this discontinued marvel of engineering. So, this is a spring & guides change only. Will be really cool to see how the gun performs after it, but also important that I can go back if so inclined.
 

[HectorMedina]

Hope you enjoy it!

I was bummed when they were cancelled...

Love to know if Hector's "hot spring" boosts power + 100 FPS?

May we assume that at 12 fpe, it shoots dead calm?

-Y

Just a comment:

I supplied the guide and tophat turned to average dimensions of the Titan #1.
It's up to Ilimakko to fit the right sized spring.
I've found up to 20 fps differences in output MV just on account of "guide-to-spring" fit. And looseness is not a solution. I've also found more than 20 fps differences between loose guides and tight (but not "nailed in") guides. 20 fps in FAVOUR of the tight guide.

It's a bit astonishing how much energy is lost when the spring is allowed to vibrate and reverberate.

As good as Titan springs are, tolerances in spring making are, by necessity, not too tight. So I hope that Ilimakko can find two or three springs that fit properly.
It is also ABSOLUTELY essential to "de-horn" both ends of the spring.
The common/commercial way of forging, squaring and grinding the ends leaves a "horn" on the inside that needs to be taken care of BEFORE installation.

This is not a Titan, it's a JM spring, but it's the handiest image I have at hand:



And this is how it should end up:


A "horned" spring will make you feel that the guide is tight, but it is an illusion.

Hope this clarifies things.

Keep well and shoot straight!





HM

[Mossonarock]

Marty asked about opening up the TP. I want to be certain about this too.
Is it true that the 16j and 23j LGVs have the same size TP and therefore "opening up the TP" is unnecessary?

[MartyMcFly]

Marty asked about opening up the TP. I want to be certain about this too.
Is it true that the 16j and 23j LGVs have the same size TP and therefore "opening up the TP" is unnecessary?

I can’t confirm for sure but I remember reading that the German low power version had a 2.6mm port,  while the others are around 3.1mm. That said, I’ve read on some UK or SA forum about guys enlarging them all the way to 3.4mm. I’m sure someone around here has better info.

-Marty

[HectorMedina]

My TP is about 3.2, hard to measure without removing the barrel. And it is a 0.177" cal version, theoretical 23 joules, but it never yielded that until I replaced the powerplant.

In 0.22" it should be the same.

Keep well and shoot straight!





HM

[Mossonarock]

I recently acquired a .177 LGV Challenger that produced up to 22J when new according to the AoA paperwork supplied with the gun by the previous/original owner- 8.2gr pellets at 940fps. This gun has been through several hands. The person I bought it from had no idea who did what to it. I took it apart to clean and relube and whilst I had the barrel off I measured the TP as best as I could. I measured approximately 3.32mm. I received the gun in a detuned state and it currently produces 17J- 9.57gr pellets at 780fps. Soon, I'll take a measurement from my fully OEM 16J .22cal LGV Competition Ultra. I'll post a separate thread about all that.

[Toxylon]

Cool, Tim! Information rulez

Got to wonder if there's something wrong with the Challenger, having been through several hands? Hope not, or at least that you got it for a reasonable price and can coax a real shooter out of it.

[HectorMedina]

Hate to rain on your parade, but Walther/UMAREX used to run their OEM guns in the "Diesel" gun range.

Based on the Cardews' terminology, these are my definitions: an airgun is operated in the "blow gun/bellows gun" regime/region when the transfer port transfers air, there is little high temperature in the cycle.
A "Pop gun" does develop a temperature spike with the pressure spike, this creates a plasma that is what gets moved through the transfer port
"Diesel" gun is a gun that uses part of the lubricant in the cylinder on each shot to add energy to the shot cycle.

The Walther lube, the size of the spring, the TP, the seal, everything is somewhat designed to run with some degree of combustion. Even the amount of lubricant provided by Walther in their kits tell you that they EXPECT you to use a lot more piston lubricant than spring lubricant.

Run the Walthers as "pop-guns" (the quasi-adiabatic, plasma producing shot cycle of a HP AIR gun lubed with modern, non-diseling lubes) and they drop a few ft-lbs from the initial shots chrono data.

"Diesel guns" are not as steady and consistent as "Pop-guns", and so, for maximum accuracy, the "Pop gun" regime is more desireable for target guns. For hunting guns, a "Diesel" regime might be acceptable.
There truly is no right nor wrong answer/decision. It all depends on the user, as long as the user is well informed and the decision is taken with full conscience of the consequences, everything goes.

;-)

Keep well and shoot straight!





HM

[Toxylon]

Hector,

Rain has almost zero effect on my parade

Upon reading the Cardews' later, 1995 book a year or so back, I was blown away by their experimental result of a .22 cal HW35 relying on combustion for more than one-half of pellet KE - this basically means many springers are firearms, not air arms! I'm happy with that.

Just like the Cardews point out, combustion (note, not "Diesel" anymore) is the "phase in which most high powered sporting spring rifles operate." In other words, it's business as usual, outside the target competition realm.

"Diesel guns" are not as steady and consistent as "Pop-guns", and so, for maximum accuracy, the "Pop gun" regime is more desireable for target guns. For hunting guns, a "Diesel" regime might be acceptable.

I fully expect all of my spring-powered airguns to work in the combustion mode. Literally millions of game animals have been harvested, as well as millions of titillatingly small groups on target faces shot, with combustion phase sporting airguns. I think there is zero need for the qualifier "might be acceptable".

[HectorMedina]

I fully expect all of my spring-powered airguns to work in the combustion mode. Literally millions of game animals have been harvested, as well as millions of titillatingly small groups on target faces shot, with combustion phase sporting airguns. I think there is zero need for the qualifier "might be acceptable".

Ilimakko;

Research proves that when you use a gun in the "Diesel" (it IS a "diesel" cycle when the compression acts as the ignitor of the fuel) region, the piston bounce back can reach between 40% and 99% of the complete stroke, in extreme instances, guns can be made to re-cock.

Using the springs in that region makes them work twice or thrice per shot.

Life of the springs goes with cycles. Life of seals goes with cycles. Forces goes with the direct proportion of pressure, and that spikes dramatically between the "pop gun" regime and the "diesel gun" regime. Pins, holes, retaining elements' lives go with the square of forces applied.

As long as that is understood, it's OK to use the gun in whichever way you want. My problem comes when someone complains about springs "only" lasting 5k shots. Of seals burning. Of pins elongating their holes, or screws loosing a bit of threads.

All these, to ME, warrant the use of the "might".

But, to each his own. My "mission" here is just to make sure that shooters are informed.

Keep well and shoot straight!




HM

[Toxylon]

Hector,

In the interest of clarity, let us use the terms as the Cardews laid them out in their seminal 1995 work "The Airgun from Trigger to Target".

You have already admirably covered the 1) Blowgun phase, as well as the 2) Popgun phase. But you seem to have a mixup or misunderstanding, maybe an exclusion of the middle-type, of the following 3) Combustion and 4) Detonation phases.

In the comments above, you equate any gun that ignites combustible substances in the firing sequence as "Dieseling", supplied with catastrophic results such as airguns re-cocking themselves upon firing (straight off the Cardews' book, p. 27). But this is a part of the Detonation phase, that the Cardews' renamed from "Dieseling", to clarify the issue.

The key here is that between the desireable Popgun phase of the target springer, and the catastrophic Detonation phase of the misfunctioning, mis-lubricated springer, there is the desireable Combustion phase, in which most powerful field springers operate in, without issue. The Cardews are very clear on this.

When it comes to the perks of the gentle Popgun phase, sans combustion, the Cardews write:

"Spring guns designed for high-level competition shooting, work in this [Popgun] phase, and are capable of producing shot to shot velocity variations of only a couple of fps."

When I chronoed my factory-lubed, by your description well in the "Diesel range" (sic) OEM LGV, the velocity variations were within 4 to 6 fps within pellet make. Maybe they would have been 1 to 3 fps, if the gun had operated in the Popgun phase. I'll take that drastic reduction in stability for the lethal KE and flat trajectories in exchange.

[Toxylon]

re: TP size of LGV's .:

I found a note of mine, gleaned off a tapatalk LGV discussion from 2014:

"The port on the 22 cal is aprox 20 % smaller [than the .177 cal]. Drilling out actually slows it down 15fps or so."

In the same discussion the extremely thick receiver front end of the LGV, and the resulting abnormally long transfer port, was named as a literal bottleneck in the power production of the LGV; with a normal, 6 mm or so TP length instead of the 25 mm or so in the LGV, the piston stroke of the gun would've reportedly easily produced 18 fpe in .22 cal.

[Mossonarock]

Regardless of dieseling (interesting turn this conversation took), I'm sure my gun was deliberately detuned by swapping the 23j spring for a 16j. The current spring is kinked on the end towards the top hat and it doesn't fit so tightly on the spring guide. The current spring probably isn't even made by Walther and was lightly greased with moly. The spring twanged and buzzed a lot before I cleaned and greased it but its still not completely settled down. I'm sure I need a new spring/guide/top hat to make that happen. I'm not sure I want to go full 23j; I'm afraid I'll need to use a spring compressor if I did that. Currently, I don't need a spring compressor to open the gun up and I like that. Perhaps someone can chime in on their experiences with working on an LGV with a 23j spring. My current project with it is to cut the stock down to make the LOP fit me and to fill the stock with something to deaden the sound. I'm also trying to figure out how I want to scope it but for now I have a peep sight on it.

I never knew that airgun manufacturers actually expected their guns to diesel even after moving away from leather piston seals, and engineered their guns around that expectation. I'm not sure what to think about that.

After cleaning and regreasing and a bunch of shots to settle it in, this gun produced avg standard deviations of 1fps, rarely as much as 3fps, with 20 shot strings. Very consistent this gun is even with the kinked spring in it.
This gun will never win a beauty contest but it definitely has potential.

[Toxylon]

I never knew that airgun manufacturers actually expected their guns to diesel even after moving away from leather piston seals, and engineered their guns around that expectation. I'm not sure what to think about that.

May I suggest taking it with a grain of salt.

Combustion is a normal phenomena with high-power springers. Detonating (Dieseling) is not. Combustion is not harmful to the gun. Detonating (Dieseling) is. 

[Mossonarock]

I really think there is a lot of confusion misunderstanding regarding dieseling/detonation. In the automotive industry, diesel engines combust their fuel; therefore, combustion is dieseling and that's how I personally view it. I have a strong chemistry background. Detonation is when your gun blows up, imo anyway. There's low levels of dieseling and there's high levels of dieseling, and a lot of variables that go into how strongly a gun will diesel.

So, to get back on track, how about those TPs, 16j vs 23j springs, and chrono data? lol.

[subscriber]

Combustion is a normal phenomena with high-power springers. Detonating (Dieseling) is not. Combustion is not harmful to the gun. Detonating (Dieseling) is.

What starts combustion in a spring airgun, if not compression ignition?  What is compression ignition, if not dieseling?

The correct definition of detonation is combustion so rapid, the flame front travels through the material being burnt as a shock wave, at the speed of sound in that material, at that temperature and pressure. 

In the context of spring airguns, "detonation" simply indicates that a large enough volume of fuel (usually oil mist)  burned rapidly enough to potentially cause damage - especially if it is repeated too many times. 

You become aware of "detonation" because of the noise heard and vibration felt.  If after shooting the airgun a number of times while producing unusually strong vibration and noise, the spring broke, or the piston or breech seals started leaking, then you know it was "detonating" for sure.

You can also be aware of dieseling that is strong enough to drive a typical pellet out the muzzle at just over the speed of sound - producing a loud crack.  That need not be damaging to the airgun, if it is caused by excess factory grease burning off.  If dieseling started directly after someone oiled the compression chamber, then the dieseling could be much more violent, depending on what oil, how much; and what airgun.

There is a myth that you can stop an airgun from dieseling by shooting heavy pellets.  All that does is reduce the velocity of the pellet below the speed of sound; thus usefully removing the loud crack.  However, heavier pellets typically produce higher peak pressures and temperatures than lighter ones, thus increasing the tendency to diesel.  What is useful about shooting heavy pellets then, is that they burn off excess lube faster than light ones, without disturbing the neighbors.  They do this, not by preventing dieseling, but by encouraging it - just without announcing it.  After the excess lube is burnt off, the velocity of lighter pellets should have dropped below the speed of sound.

I have a "magnum" gas-springer with original factory lube that has no visible haze in the barrel, directly after shooting 7 or 8 grain pellets.  But, when breaking the barrel directly after shooting 10.5 grain pellets there is a brown haze visible, so thick one cannot see through the barrel.  Strong evidence of compression ignition caused by higher peak pressure and temperatures, due to shooting the heavy pellets, liberating some of the oil fraction of the factory grease in the compression chamber.  Along with the brown haze, is a faint burnt oil smell.

Many people would not notice such combustion until it is so heavy that there is a smoke cloud on the shot; with a wisp leaving the muzzle after wards.  And a strong burnt oil smell.

Arguing that something is combustion, or dieseling, or detonation is like arguing about dropping a pellet, a can of pellets, or a pallet of pellets your foot.  Calling the latter a "projectile" because it did some damage; while arguing that the other two are not projectiles...

[phoebeisis]

Hate to rain on your parade, but Walther/UMAREX used to run their OEM guns in the "Diesel" gun range.

A "Pop gun" does develop a temperature spike with the pressure spike, this creates a plasma that is what gets moved through the transfer port
"Diesel" gun is a gun that uses part of the lubricant in the cylinder on each shot to add energy to the shot cycle.

The Walther lube, the size of the spring, the TP, the seal, everything is somewhat designed to run with some degree of combustion. Even the amount of lubricant provided by Walther in their kits tell you that they EXPECT you to use a lot more piston lubricant than spring lubricant.

Run the Walthers as "pop-guns" (the quasi-adiabatic, plasma producing shot cycle of a HP AIR gun lubed with modern, non-diseling lubes) and they drop a few ft-lbs from the initial shots chrono data.

"Diesel guns" are not as steady and consistent as "Pop-guns", and so, for maximum accuracy, the "Pop gun" regime is more desireable for target guns. For hunting guns, a "Diesel" regime might be acceptable.



Oh I  screwed up this quote cut-the below are my questions for everyone
Hector et al-

1) by modern, non-dieseling lubes do you mean those described as silicone lubes-harder to ignite than carbon based lubes ?

2)The -crossman-silicone chamber oil-colorless transparent stuff tiny tubes-  it is less likely to ignite or mostly impossible to ignite?

3) the crosman silicone chamber lube-"feels pretty slippery" why not use it on various moving parts-if you want no combustion/detonation?


Thanks

Charlie