GTA
All Springer/NP/PCP Air Gun Discussion General => Air Gun Gate => Topic started by: Mossonarock on November 23, 2018, 02:57:21 PM
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I've had a Hatsan Dominator with a metal "spring" and just today received a Hatson Dominator with a gas piston "vortex". Both in .25 cal.
I wanted to compare the two rifles in all respects.
So, as soon as I got the Dominator Vortex, I chrony tested it. The first couple shots were about 915 fps with Barracuda Green 19.91gr. My jaw hit the floor. I was not expecting to see that. However, each shot was slower and by the tenth shot or so the fps was down to 815fps. Unfortunately, for some reason my chrony was only registering every third shot or so. hhmpf.
What I am wondering if the initial high fps was from an extra push provided by detonation of the factory lubes and as it burned off the fps dropped or what? Any ideas? The smoke coming out of the barrel was quite dense.
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If the gun sounds like a .22lr going off, it's dieseling (detonating). There can also be some combustion going on without the detonation. The smoke is another indication. That usually goes away after a few shots, and the gun will continue to "settle/break in" over the next few hundred shots.
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Dieseling is accompanied by an increase in velocity and detonation by a decrease although detonation is a a more violent occurence. All depends on the fuel available.
There was a thread just recently that detailed the two events that explained it well.
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When I get a new spring or gas ram gun (new or refurb) or a spring/gas ram gun I've tuned and lubed myself I never do the first few break in shots with lite for caliber pellets. And I never use lite for caliber alloy pellets either for break in. I always shoot the first few shots with mid to heavy weight for caliber lead pellets. Your opinion and experience may be different.
Nathan
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yep thats what is happening, just got a new one today. it's still smok'n after maybe 20+ shots. first shot sounded like a BB cannon, had to wait for the smoke to clear, so I could see to reload. Kinda like shooting a chinese Black powder gun
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Yes, 919 fps in a box stock .25 cal springer is, for sure, dieseling.
Detonation is what explosives do. It's dieseling, or burning. Even gunpowder burns. Burns all the way down the barrel. Detonation? That's explosives. The airgun world is confused on this.
Don't fret or sweat, most new springers dielsel a bit. Clean the barrel very well. Shoukd help calm it down a bit and enhance accuracy. Then get back to us after 20-30 rounds downrange, after a good barrel cleaning, and a few groups.
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There can also be some combustion going on without the detonation. The smoke is another indication.
I have had this "issue" since i bought my fire NP. Every single shot causes smoke in the barrel, even a year and thousands of pellets shot....
Anything else that can cause smoke?
This to me would indicate there is to much lube in the gun, and it's getting past the seal. I've had a few new guns that had to be cleaned up, and lubed the right way. Not to mention some nicked seals from the factory.
Tom
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About smoke- if it is accurate, don't worry about the smoke.
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...Every single shot causes smoke in the barrel, even a year and thousands of pellets shot....
Ah memories...Does it smell like a candle that had just been put out?
I bought my CFX refurbished. Every now and then I'd get a cracking shot. ("Ooops! Was that me?"...and look around for witnesses.) I forget how many shots I put through it before those stopped, but it was way more than 200. I got smoke a lot early on, but that would happen off and on for a longer while.
No smoke these days, but I can still smell the candles :)
One of these days I'll replace the seal and try to lube it right.
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I've cleaned out the compression chamber and all that. Relubed it. No more smoke now.
The fps settled down to about 700 with the Barracuda Greens.
Yeah. In my opinion, dieseling vs detonation is kinda like six of one or half a dozen of the other.
Either way, lubes combust whether its an explosion or smolder.
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There is much dogma expressed about dieseling; even when it is patently wrong:
1. "To stop a new spring airgun from dieseling, use a heavier pellet".
2. "if it cracks like a .22 rimfire it is dieseling". Thus; "if it stops cracking like a rimfire, it is no longer dieseling."
Obviously, belief #1 stems from #2:
Heavier pellets raise the peak pressure in spring airguns, thus more readily generating air temperatures high enough to ignite any lubricant mist that may be present. Therefore, heavy pellets (for the caliber) are more likely to diesel than light ones.
The above dogma about using heavy pellets to suppress dieseling stems from the fact that heavy pellets are less likely to be travelling over 1100 FPS (or whatever the speed of sound is at your location), even when dieseling is involved. Thus heavy pellets will induce significant dieseling more often than light pellets.
Yet, they won't announce with the sharp crack that lighter pellets often produce when dieseling occurs with them.
Just like with an engine, if your airgun runs rough, stop to consider what you can do to smooth out its operation.
If a spring airgun smokes, it is burning something, probably lubricant. That oil or grease is being lit via compression ignition; AKA dieseling. Unless your airgun is extremely loud and jolts unusually in your hands, it is not going to self destruct. So, the idea that your airgun could be dieseling without you knowing, and thus secretly destroying itself is rather ridiculous.
Early spring airguns had leather piston seals that had to be generously oiled, or they would leak air. That meant oil was always present in the compression chamber (oh the horror). Such airguns burnt oil at a slow but steady rate, and were quite accurate; despite their continuous "secret dieseling"...
What some call detonation, is just heavy dieseling. It is so severe that the airgun is "protesting" by means of obviously loud sounds and heavy vibration. Not unlike when someone lugs an old gas engine, running on too low octane fuel to the point of making it sound like a diesel. It is really saying, "if you want me to last, don't do that to me".
Heavy dieseling is likely to raise the projectile velocity by hundreds of feet per second. It is likely to vary from on shot to the next by over 50 FPS. The dispersion this causes on target should be reason enough to find a permanent "fix" or at least a mitigating factor (like using a different pellet).
For the deniers out there. Those who would be grossly insulted by claims their spring airguns are dieseling, consider this: Just because you don't see smoke bellow forth from the muzzle on every shot does not mean lubricant is not being burnt: Break the barrel on your spring airgun and look through it against the light, directly after shooting each of 10 shots in quick succession. That brown haze you see and can blow out, is smoke. Smoke is partially burn hydrocarbons. How do you suppose that got there...
Just because some airguns have an obvious haze hanging in the barrel after the shot does not mean they are in danger of disintegration. Or, in need of stripping down, degreasing and re-lubing.
If a spring airgun has a shot to shot velocity difference of less than 25 FPS, and is sufficiently accurate at your intended range; who cares if it burns a little lube along the way?
Arguing about dieseling VS detonation; and that there is a fundamental difference, sounds political; and is about as useful. Large abrupt releases of thermal pressure energy into a system not designed for it may lead to damage; especially if repeated many times. Smaller and less abrupt releases of thermal pressure energy are not going to do much at all, even if they happen hundreds of times; except make you miss your shot. Especially, if the events are inconsistent.
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"Arguing about dieseling VS detonation; and that there is a fundamental difference, sounds political; and is about as useful"
I agree hence my analogy to an explosion vs a smolder. You accurately described scenarios where an "explosion" would dramatically increase fps vs scenarios where a bit of lube may "smolder" a bit but not significantly increase fps. Either way some lube burned.
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Still just waffly opinions with no back up to them.
This information falls far short of that provided by T Domingo and others in a previous thread. They at least gave the apppearance of knowing what they were talking about and probably did.
Perhaps reading that and making some criticism of it would advance the topic.
A declaration of qualification to comment might add weight.
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"Waffly opnions"? You mean like this one?: "Dieseling is accompanied by an increase in velocity and detonation by a decrease although detonation is a a more violent occurence."
My qualifications? I understand how diesel engines work. Did you know that diesel fuel detonates/combusts in a diesel engine without sparkplugs? Anyone ever wonder how that happens? I also have a lot of experience with the requirements for fuel combustion in campstoves- alcohol, white gas, kerosene and even veg oil.
One thing I find missing in the discussions of detonation vs dieseling that I've come across is mention of lube "vaporization". When the air in the compression cylinder is compressed during the shooting cycle, the temperature of the air increases. That increase of temperature can "vaporize" some lube and it can do so without that lube combusting/dieseling/detonating. There's a lot of variables that go into play on how much so the lube vaporizes and whether or not it will diesel/detonate/etc. However, anytime that lube combusts/diesels/detonates/blah blah, it had to have vaporized first. Its just like in campstoves, fuel has to be vaporized first before it can be ignited. So, in campstoves, we have vaporizing tubes that the fuel goes through before the fuel is fed into the burner head. The trick in airguns is knowing when you merely have vaporization of lube or if that lube burned/dieseled/etc.
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Not my opinion. Relayed from those who seem to know. At least know more than I do.
Maybe they have some specific training. They write as if they do and refer to scientific papers.
I will try and find the thread.
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what is dieseling ?
« on: August 03, 2018, 04:20:37 PM »
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I hear that term in here, and no clue what it means ?
Thanks
Here is the thread. My contribution was limited to trying to understand and describe the original question but including detonation.
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One thing I find missing in the discussions of detonation vs dieseling that I've come across is mention of lube "vaporization". When the air in the compression cylinder is compressed during the shooting cycle, the temperature of the air increases. That increase of temperature can "vaporize" some lube and it can do so without that lube combusting/dieseling/detonating. There's a lot of variables that go into play on how much so the lube vaporizes and whether or not it will diesel/detonate/etc.
This inconsistency is exactly why I completely degreased the compression chamber of my D34 and only use Krytox lubrication. It has zero flash point and cannot cause or contribute to combustion. My gun never diesel's. That variable has been eliminated.
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A declaration of qualification to comment might add weight.
Now that really sound political. :)
Facts and logic trump appeals to authority; and real or claimed qualifications, every day of the week.
The textbook definition of detonation means an "explosion triggered by a shock wave, travelling through the medium at the speed of sound; where all the mass participating in the reaction is converted to gas nearly instantaneously".
This, in contrast with a flame front moving through the medium from one end to the other, or from a point radiating outwards. In deflagration, the medium is converted to gas only at the flame front; not everywhere at the same time.
The word "detonation" sounds "bad", but does not really tell you if it was a big bang; only that it was a short lived.
Detonation on a small scale might still be damaging, just like cavitation causes erosion of pump impellers: Very small events, but intense enough to flake off surface material. Especially when repeated so many times that it fatigues the material; even if only superficially. Once, some material has flaked off, it exposes new material to the small shock events, so the erosion continues.
"Detonation" in a gasoline engine can damage bearing when heavy; and erode holes in piston crowns when light, but continuous. With the latter, it flakes off the protective aluminum oxide layer, exposing the fresh aluminum to further oxidation; until there is a hole through the piston crown...
If your springer diesels or detonates so heavily that it recocks itself, you are not going to enjoy shooting it very much, or for very long...
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One thing I find missing in the discussions of detonation vs dieseling that I've come across is mention of lube "vaporization".
Wasn't this close enough for you?
Heavier pellets raise the peak pressure in spring airguns, thus more readily generating air temperatures high enough to ignite any lubricant mist that may be present. Therefore, heavy pellets (for the caliber) are more likely to diesel than light ones.
After all, the fuel in a diesel engine is just a fine mist after injection, yet it ignites. True vaporization happens after the fuel mist temperature goes up from compression; and much more from the early combustion. Thus the smaller the initial droplets, the easier they ignite; because it takes less energy to actually vaporize them.
What is the difference between mist and vapor? Mostly particle size: Mist droplets are composed of clusters of multiple molecules, while vapors (gases) are composed of single molecules of a given substance.
Hence, higher viscosity sticky grease is harder to whip up into a mist than a thin oil; which is why magnum springer compression chambers should never be lubed with regular oil...
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Good grief.
Since somebody is all in a a tizzy over my waffly comments...
Long story short, 900+ fps .25 cal at 19+ grains is a sign of a load of oil in the barrel and/or compression chamber, either brand new gun or a bad seal, or etc.
With the really light 14-16 grain .25 ammo, yeah I could see 900 fps a realistic achievement in a very powerful springer, without the "extra burning oil".
FYI cleaning a barrel really well before the first shot really cuts down the dieseling of a brand new springer.
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I hope some of you find this thread both entertaining and informative. Here, the secret life of machines video series examines the energy released inside internal combustion engines; petrol and diesel:
Petrol compared to black powder:
https://www.youtube.com/watch?v=83z--znNBcA&feature=youtu.be&t=179 (https://www.youtube.com/watch?v=83z--znNBcA&feature=youtu.be&t=179)
Compression ignition principle:
https://www.youtube.com/watch?v=gfr3_AwuO9Y&feature=youtu.be&t=984 (https://www.youtube.com/watch?v=gfr3_AwuO9Y&feature=youtu.be&t=984)
Rewind the second video to see the rest of whole program from this amusing series.
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I know I shouldn't but ,somewhere I read that a new springer or NP rifle should be dry fired a couple times to remove excess lube and to "set" the piston seal. Don't remember where I read it.Please correct me if I'm wrong! This ought to be good.
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I know I shouldn't but ,somewhere I read that a new springer or NP rifle should be dry fired a couple times to remove excess lube and to "set" the piston seal. Don't remember where I read it.Please correct me if I'm wrong! This ought to be good.
Actually, Richard, the Beeman P1 / HW45 has a teflon piston seal that is seated by try firing it a few times. That forces into a shape close to the cylinder it runs in, and ensures a good seal. Quite likely that some other airguns manufacturers use the same "hammer forming" process. Depends on the seal type, I think.
The Slavia 634 (new old stock) I got recently states something in the user manual about blowing the oil out of the barrel via dry firing. I assumed that was a typo, as elsewhere it states not to dry fire it...
The barrel looked shiny and pretty dry when I got it; to the point of making me wonder if someone had perhaps already shot with this particular gun. I have another new (old stock) Slavia on the way, and will see if it arrives full of oil.
My way of cleaning the barrel on a new airgun, is to saturate a cleaning pellet with thin oil, load it; then load a wadcutter behind it and shoot them through together (never just a cleaning pellet). If I think it necessary, I will repeat this a few times; then go straight to just lead pellets, without drying the bore. Everyone has their own way of doing cleaning their guns; and that is all good.
I don't care if there is a little smoke initially when switching over to "dry" pellets. What I can tell you, is that if you fill the rear of the pellet skirt with a drop of the same oil, it will diesel so energetically that the pellet goes supersonic. When the oil is partitioned off in front of the pellet the discharge sounds just like with a dry lead pellet.
The fact that trace oil clings to the bore afterwards is a good thing in my opinion, rather than something that should be avoided at all costs: Such trace oil and the manner of placing it there, is how I prepare my airguns for storage at the end of a session; unless I know I will shoot some more the same day. I simply never want to see rust in the barrel, and my method of oiling the bore works without dragging a cleaning rod through it.
If I had need to shoot critters on an opportunistic basis, then each shot taken with trace oil in the barrel would probably have a first shot or three deviation from the normal POI; so I understand why some people never pull oily patches through their barrels (only dry ones, to remove lead "lumps"; not all traces of lead). For them, it takes too many shots to re-stabilize the point of impact. I don't mind if the first 5 shots land a little off. The paper rat targets I might shoot never move, even when I miss a perfect head-shot...
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Sorry if some of us use the terms diesel and detonation in a manner the is not scientifically accurate, but it's easier to explain to a new airgun shooter. To me a little whiff of smoke from cosmoline burning off the rifling and an extra 50 fps is one thing and a loud crack that is louder than a CCI Stinger at 2000 fps, where I'm surprised that I don't have pieces of the spring in my forehead is the other. Calling them the same might be scientifically accurate, but I think we need to discourage the latter.
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Sorry if some of us use the terms diesel and detonation in a manner the is not scientifically accurate, but it's easier to explain to a new airgun shooter. To me a little whiff of smoke from cosmoline burning off the rifling and an extra 50 fps is one thing and a loud crack that is louder than a CCI Stinger at 2000 fps, where I'm surprised that I don't have pieces of the spring in my forehead is the other. Calling them the same might be scientifically accurate, but I think we need to discourage the latter.
I think if the air rifle comes apart in your hands, calling it detonation is perfectly appropriate :)
I honestly believe that oil in the barrel burning off is not as serious as the same oil layer in the compression chamber igniting, for these reasons:
The amount of oil that can cling to the barrel wall is limited by its tiny circumference; VS the very large space between piston and compression chamber.
The transfer port will limit the flow of air in the event the pressure suddenly rises due to a significant combustion event. With combustion in the barrel, the TP acts as a restrictor that creates a pressure drop and limits back-flow, thus shielding the piston somewhat from the pressure spike in the barrel. If a large combustion event occurs in the compression chamber, then TP flow restriction acts to make the event in the compression chamber harder on the piston and spring.
The barrel wall is way stronger than any pressure you can generate via compression ignition by means of a lead pellet as a plug (Glue the pellet in place and all bets are off :) ). The compression cylinder has a much larger diameter and a thinner wall, hence it is much more fragile than the barrel to over-pressure. Even then, the compression chamber has a "blow-off" safety valve protecting it, in the form of the piston and mainspring.
The O-ring at the breech on break barrel is likely going to leak and act as anther release valve. Of course, this is not good for the O-ring; if repeated many times.
Thus, the idea that you could disintegrate a spring air rifle by dieseling oil seems absurd. Perhaps if you filled it with a stoichiometric mixture of nitromethane and pure oxygen, you might break the spring, bulge the compression tube and split the stock.
Consider the pressure event that results from the piston slamming into the air column at the front of the cylinder in normal operation. That resulted from the piston running all the way from the rear of the compression cylinder after de-latching from the sear. If a dieseling event does not manage to push the piston all the way to the rear of the piston stroke, just how much energy did that event have, compared to the energy normally released by the spring?
Peak gas pressure is another consideration and an important one, but short of bulging the compression tube (or blowing the end off), it is really the spring, piston seal and breech O-ring that suffer from heavy dieseling.
Injecting several drops of CLP into the transfer port of a spring air rifle is definitely contraindicated, and new airgun owners should be warned about proper lubricants and how to apply them. CLP's light hydrocarbon detergent content makes it even easier to ignite than pure mineral oil, or diesel. So, rather than preserving your airgun by lubing the piston with whatever oil you happen to have, you may be damaging it. Certainly, a number of heavy diesel events, or frequent ones that increase the report, may drastically reduce the life of the spring and burn the piston seal. This is the opposite of making choices to increase the life of your new air rifle.
Burning off the two drops of oil that adhere to the surface of a new barrel don't qualify as abuse in this regard. In addition to the reasons why in-barrel combustion are not "as bad", the fact that the first two pellets will squeegee out the bulk of this oil without burning it, is the other reason.
I shoot firearms with trace oil in the barrel based on these criteria:
Is the oil just enough to make the barrel shiny; or does it obscure the rifling, or pool at the bottom? If the latter, patch it out before shooting; else blast away.
If it is a bottle neck case centerfire rifle and the situation is not an emergency, then patch the chamber wall dry and check the bore for any obstruction before shooting.
Most handgun calibers get shot directly with trace oil still in the chamber and barrel. There are exceptions where the lack of case grip due to oil causes case head flow, causing sluggish cylinder rotation, such as .44 Mag.
Service pistols with "carbon steel" barrels carried in holsters a lot and shot very little should have trace oil in the barrel. Else they will rust. Rust impedes projectile travel a lot more than a little thin oil...
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I, too, seriously doubt you could break a quality spring gun with a few drops of oil.
But if you do it a few times, I can tell you for certain it will break the spring. As sure as heavy pellets can break a spring, deiseling it will break it so much faster.
And it has been documented, deiseling a springer could possibly re-cock the gun if it is violent enough, something to keep in mind. That is alot of force.
Not to mention, pellets blown down the bore without their skirts, leaving the barrel plugged, and etc.
It is certainly not a big deal, a little bit of deiseling in a new rifle. But it can do a lot of damage if you make it a habit.
Depending on the chemical you choose, it certainly could do serious damage. Weihrauch tried to build a rifle built for deiseling with ether, didn't work out because the piston seal couldn't hold up to it. That, and it was too erratic.
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But if you do it a few times, I can tell you for certain it will break the spring. As sure as heavy pellets can break a spring, deiseling it will break it so much faster.
Absolutely right. People worry about shooting heavy pellets reducing spring life (when that is their most accurate pellet). Frequent heavy dieseling will be very hard on the spring; and break it in short order.
And it has been documented, deiseling a springer could possibly re-cock the gun if it is violent enough, something to keep in mind. That is alot of force.
A lot of force, but no more than you apply when you cock it. So, not really that much; except if the piston slams into the endcap, as if it were compressing a spring twice as long.
Certainly, if your spring air rifle recocks itself, stop what you are doing and call a professional...
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But if you do it a few times, I can tell you for certain it will break the spring. As sure as heavy pellets can break a spring, deiseling it will break it so much faster.
Absolutely right. People worry about shooting heavy pellets reducing spring life (when that is their most accurate pellet). Frequent heavy dieseling will be very hard on the spring; and break it in short order.
And it has been documented, deiseling a springer could possibly re-cock the gun if it is violent enough, something to keep in mind. That is alot of force.
A lot of force, but no more than you apply when you cock it. So, not really that much; except if the piston slams into the endcap, as if it were compressing a spring twice as long.
Certainly, if your spring air rifle recocks itself, stop what you are doing and call a professional...
But consider the violent change in direction to re cock the gun. That spring just went from coming freely uncoiled, to be snapped back to nearly coil bound, in an instant. That is a whole lot more force that what it recieves in a cocking stroke. If you tried to re cock it as soon as you pulled the trigger, it would for certain damage the cocking shoe, tip of the cocking arm, whatever it connects to the piston with. Liable to shear it off completely.
That much force, can do a whole lot of damage!
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But consider the violent change in direction to re cock the gun. That spring just went from coming freely uncoiled, to be snapped back to nearly coil bound, in an instant. That is a whole lot more force that what it recieves in a cocking stroke.
Yes. Bad for the spring. Very bad.
The rest of your statement about recocking the gun just after it fires being hard on the cocking shoe is not relevant, as those components are not involved in dieseling.
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But consider the violent change in direction to re cock the gun. That spring just went from coming freely uncoiled, to be snapped back to nearly coil bound, in an instant. That is a whole lot more force that what it recieves in a cocking stroke.
Yes. Bad for the spring. Very bad.
The rest of your statement about recocking the gun just after it fires being hard on the cocking shoe is not relevant, as those components are not involved in dieseling.
Maybe you should think it through before posting such a hasty reply.
I never implied the cocking shoe would be damaged by deiseling.
You posted that the pressure that occurred When a gun was recocked after deiseling was no more than when you cock it by hand.
Well? It is actually a WHOLE LOT MORE than when you cock it by hand.
Possibly enough to even bulge the tube. Might even create enough pressure to bulge the tube without cocking it!
Unless you can cock the gun faster than it can complete a shot cycle, you will never apply marginally the same amount of force as would be generated under those circumstances.
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But, I guess I should depart from the thread.
No waffles being served here, only logic.
Thanks, and you're welcome.
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You posted that the pressure that occurred When a gun was recocked after deiseling was no more than when you cock it by hand.
Well? It is actually a WHOLE LOT MORE than when you cock it by hand.
What I said is quoted below. I compared the energy seen in recocking; then went to state that the pressure was another matter. So, you are getting ahead of yourself with your speed reading.
Consider the pressure event that results from the piston slamming into the air column at the front of the cylinder in normal operation. That resulted from the piston running all the way from the rear of the compression cylinder after de-latching from the sear. If a dieseling event does not manage to push the piston all the way to the rear of the piston stroke, just how much energy did that event have, compared to the energy normally released by the spring?
Peak gas pressure is another consideration and an important one, but short of bulging the compression tube (or blowing the end off), it is really the spring, piston seal and breech O-ring that suffer from heavy dieseling.
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You posted that the pressure that occurred When a gun was recocked after deiseling was no more than when you cock it by hand.
Well? It is actually a WHOLE LOT MORE than when you cock it by hand.
What I said is quoted below. I compared the energy seen in recocking; then went to state that the pressure was another matter. So, you are getting ahead of yourself with your speed reading.
Consider the pressure event that results from the piston slamming into the air column at the front of the cylinder in normal operation. That resulted from the piston running all the way from the rear of the compression cylinder after de-latching from the sear. If a dieseling event does not manage to push the piston all the way to the rear of the piston stroke, just how much energy did that event have, compared to the energy normally released by the spring?
Peak gas pressure is another consideration and an important one, but short of bulging the compression tube (or blowing the end off), it is really the spring, piston seal and breech O-ring that suffer from heavy dieseling.
Energy in a gun that deiseled so hard, it recocked itself, still far greater than when you cock it. Think about the velocity of the piston reversed hard enough to recock it, how fast it must return.
You want to catch me up on verbiage, or even to continue this with me at all, we can do it in private messages. I'm done with you, and this thread.
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Energy in a gun that deiseled so hard, it recocked itself, still far greater than when you cock it. Think about the velocity of the piston reversed hard enough to recock it, how fast it must return.
The bold portion is true, but only if the piston slammed into the back end of the compression tube (as made clear in my earlier post).
This is like throwing a bowling ball up in the air (with gravity instead of a spring, pushing it down). If you can manage to ignore air resistance due to its insignificance; all of the ball's velocity is converted to height on the way up. All of its height is converted to velocity on the way down.
No matter how large your peak force and peak acceleration when throwing that bowling ball upwards, the velocity at which it leaves your hand dictates how high it will go. The height reached at the top of its travel dictates the ball's velocity on the down. Just as if it were driven by a very large volume gas ram, with a near constant "spring rate".
Now, consider that you are throwing the bowling ball upwards in a room with a vaulted ceiling. As long as the ball just kisses the ceiling on the way up, the energy you imparted is the same as the energy the ball has on the way down. It matters not if you used 160 lb applied over one foot, or 80 lb over two feet to launch it. It is only if the ball slams into the ceiling that "extra energy" can damage anything.
What damages the spring in a dieseling airgun is not the fact that the piston is driven backwards, but making the spring coils clash into themselves violently. So it is acceleration and jerk, driven by gas pressure that does the damage, rather than too much energy. Even if the piston never comes close to traveling far enough to recock.
We suffer from the flip-sides of the same disease: You want to prove me wrong. I want to prove me right. What is amusing, is that we agree in principle about all the important details, But, you need to have the last word. So, go for it. I am done with this thread; unless someone says something sensible that has not been said before.
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I would like to publicly apologize to Bryan H for having more sport with him than really necessary.
I just found his insomnia thread in the Backroom that made it clear to any thinking person, that such arguments are contraindicated.
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Good grief.
Since somebody is all in a a tizzy over my waffly comments...
IKR......
I'm sure I had a screwed up expression on my face when I read that too.
Why... Eh, I'm not going to bother asking.... I know its pointless but I wish my opinion that its pointless was a waffle served up.
I agree that the term "detonation" ought to be dropped by the airgun community.
I also want to express my concerns with metal fatigue after my experience last night. What happened was... I broke a manual log splitter with nothing more than my own bones and muscle. Who'd a thunk a wirey guy like me could do that?
I'd say, if your airgun blew up in your face and blew to pieces, that was an explosion caused by extreme dieseling. Dieseling is when the vaporized lube particles actually combust whether just a wee poof or it blows your airgun up and sends shrapnel flying. If that's a waffle for you, then eat up!
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Hahahaha! All I am saying is, I never saw a shockwave coming from a springer. Or a firearm for that matter.
That's the difference. A supersonic shockwave that moves ahead of the explosion, you can see it if you are far enough from it. Detonations are extremely violent and fast.
I'm guilty of calling it detonation as well. I agree we gotta stop using that terminology. More like ignotion, or combustion??? Combustion I think is the correct term according to the Googles. For sure it ain't detonation!