moderators

[CROWalYeLikUrDEAD]

I agree with tranztaz , dekers you commented very ignorantly on my post also, people are debating on subjects they want to know more about not some ignorant man coming in asking them "what are they on?" The answer is there on pigeon watch forum asking for some answers and what people think, nothing nice to say - sit back out off the conversation, your not debating about it you jump straight in condemning everyone if they think different to you.

[joe soapy]

There is some good footage of birds ducking airgun pellets on the tube

[Traztaz]

Its not ducking , its reaction to sound. What we would call jumping.

[Dekers]

I am on real time testing with thousands of pounds worth of equipment..............you? I did not say the target will duck I said flinch! You ever walked into something unexpectedly and had your body move so fast that you cricked you neck?

There is no hear and understand, its reaction, no more no less.

Maybe I am wrong , but I really really do not think so. I can prove what I say, can you?

 

The speed of sound is known, the speed of the bullet is known, what I don't know is how fast a bunny can react...DO YOU?

 

On top of which everyone seems to be forgetting these are Sub Sonic rounds, just how much noise do they make in the great scheme of things for anything to react to them at all?

[Dekers]

I dont see how people are saying it doesnt make much of a difference... It takes a huge brunt of the bang away, there is still the subsonic crack but its not half as bad.. And also when you're down range its a heck of a lot quieter.

 

I wudnt go without one on mine again

 

 

 

What's a subsonic crack?

 

 

no such thing I am afraid. Subsonic flight can not be heard. Its slower than the speed of sound, hence sub sonic...............do I need to expand?

 

My point entirely, perhaps I should have put it more bluntly.

 

 

 

 

 

Edited June 29, 2013 by Dekers

[Dekers]

I agree with tranztaz , dekers you commented very ignorantly on my post also, people are debating on subjects they want to know more about not some ignorant man coming in asking them "what are they on?" The answer is there on pigeon watch forum asking for some answers and what people think, nothing nice to say - sit back out off the conversation, your not debating about it you jump straight in condemning everyone if they think different to you.

 

Say, think and dream what you like, the physics are there for all to see, its nothing to do with thinking different, its about facts!

[Dekers]

Its not ducking , its reaction to sound. What we would call jumping.

 

Call it what you like, but the bunny is not going to react to anything until it hears something, unless you are also suggesting they are physic and know when you are going to pull the trigger.

 

If he can react in any way between the time he hears the noise of the bullet approaching/being fired and the time the bullet arrives I suspect he is on better pills than you!

[tjm160]

Call it what we will, I know what you mean Traztaz, I've had rabbits flinch/duck just before the crucial moment (with the HMR), causing the shot to go over their heads. Did they hear the round, certainly not, I hadn't (quite) fired at that stage, perhaps it was a sixth-sense Whatever, a .22 round is a lot slower than a .17 HMR, which does give bunnies (a little) more time to react. Do they react based on moderated vs. unmoderated sound on a .22 vs .17 HMR, I don't know but still wouldn't shoot without one. I also wouldn't wish to be very rude in forcefully and totally discounting your perspective.

[Dekers]

Call it what we will, I know what you mean Traztaz, I've had rabbits flinch/duck just before the crucial moment (with the HMR), causing the shot to go over their heads. Did they hear the round, certainly not, I hadn't (quite) fired at that stage, perhaps it was a sixth-sense Whatever, a .22 round is a lot slower than a .17 HMR, which does give bunnies (a little) more time to react. Do they react based on moderated vs. unmoderated sound on a .22 vs .17 HMR, I don't know but still wouldn't shoot without one. I also wouldn't wish to be very rude in forcefully and totally discounting your perspective.

 

Exactly, they appear to have reacted to something, it was certainly not the HMR as the sound would arrive after their head was removed, so why do people appear to think they react to a sub, which is very quiet anyway, it is co-incidence, it is nothing to do with hearing the sound of a sub on its way to their head!

 

It's happened to me on virtually every quarry I can think of, with centrefires as well, but I know it was simply that split second thing and it was their lucky day (or my unlucky day).

 

Suggestion of reacting to the bullet noise and therefore avoiding it is fantasy!

Edited June 29, 2013 by Dekers

[Dekers]

Dekers, have had a bad at the office? You seem to be a bit argumentative. I DON'T expect it to make the 17hmr silent but I do expect it to be longer lasting than the saks I have had before and a LITTLE BIT quieter, I don't expect the world but I think the sak can be bettered.

 

Paul

 

I totally agree, but I'm not sure how you equate costs with results, perhaps cost isn't a factor here.

 

Lifespan may be improved, and sound reduction may be marginally improved, but there have been many tests on mods with HMR and sound reduction remains good on a SAK, (there are better).

 

Also remember the SAK is Guaranteed for life against ANYTHING, Jacksons will replace it even if you run over it in your tractor for 60% of list!

 

I am not for one second suggestion experiment/development/innovation/invention/etc is not a good idea and I hope you get good results, will you be in a position to show us the finished product and get some dB measurements done?

[jeffo223]

Dekers,

The custom moderator is not a very expensive build, it's only cost me £65 which is not a great deal for full stainless steel .

I would love to give a full db report but I have only got a mk1 ear but I will give a honest opinion and pictures.

 

Paul

[Dekers]

Dekers,

The custom moderator is not a very expensive build, it's only cost me £65 which is not a great deal for full stainless steel .

I would love to give a full db report but I have only got a mk1 ear but I will give a honest opinion and pictures.

 

Paul

[dadioles]

Hi Dekers

 

For such an experienced shooter of rabbits I am surprised that you have never seen a rabbit move in reaction to the sound of a .22lr being fired and shifting position slightly before the bullet gets to the rabbit. I am not talking about great distances either, just 60 or 70 yards.

 

The word "flinch" is a much better use of language than "move". I contend that it is an involuntary response, a reflex action, hence very fast.

 

Rabbits are easily spooked and when they are in an "alerted" state they are charged with adrenaline, they will move as a "reflex action" in reaction to a sound or visual stimulus that spooks them in the same way that you will blink your eye in self protection before your brain has time to perceive the threat. Whether they are reacting to the sound or the sight of the flash I do not know.

 

Obviously as the muzzle of the gun is pointing straight at them, the rabbit is, in effect, looking straight down the barrel so maybe it is the flash of burning powder that triggers a response in the rabbit rather than the sound. The light emitted by the flash will get to the rabbit instantly (speed of light obviously), but the bullet has to accelerate from stationary and build up speed as it passes through the barrel and is then decelerating, albeit fractionally, as it makes its way to the target. That is a surprisingly slow process.

 

It is not just a matter of taking the distance from the rifle to the rabbit and calculating the time for sound to travel over that distance (as you have done). You also have to factor in the relatively slow burn of the charge and the acceleration of the bullet out of the chamber.

 

Have you ever watched the men with their antique black powder guns? The delay between applying the "fuse", the powder igniting, building up pressure and finally ejecting the lead ball is quite extraordinary.

 

A quick look on the internet suggests that a typical reaction time in a human being is about 160 milliseconds for a sound stimulus. For example hear a sound and in consequence press a button. That is much slower than a reflex action.

 

Hawke Chairgun Pro suggests that a subsonic bullet takes about 200 milliseconds to travel 60 yards and if you factor in the time after the bang and flash that the bullet takes to leave the rifle it will be even longer.

 

I contend that leaves plenty of time for a rabbit to react, even based on conscious reaction times in a human being where the nerve stimulation has further to travel, rather than the faster reflex response that a rabbit may exhibit.

 

Coffee anyone.....?

[Dekers]

I'd get a pot!

Edited June 29, 2013 by Dekers

[Dekers]

Hi Dekers

 

For such an experienced shooter of rabbits I am surprised that you have never seen a rabbit move in reaction to the sound of a .22lr being fired and shifting position slightly before the bullet gets to the rabbit. I am not talking about great distances either, just 60 or 70 yards. Yeah, seen lots of wildlife move as I pulled the trigger, but it was nothing to do with hearing the bullet heading for them!

 

The word "flinch" is a much better use of language than "move". I contend that it is an involuntary response, a reflex action, hence very fast. call it what you like, they still have to hear it to react!

 

Rabbits are easily spooked and when they are in an "alerted" state they are charged with adrenaline, they will move as a "reflex action" in reaction to a sound or visual stimulus that spooks them in the same way that you will blink your eye in self protection before your brain has time to perceive the threat. Whether they are reacting to the sound or the sight of the flash I do not know. they will not have any flash to react to until after the bullet has left the barrel, it will be behind it, that also assumes they are looking at you!

 

Obviously as the muzzle of the gun is pointing straight at them, the rabbit is, in effect, looking straight down the barrel so maybe it is the flash of burning powder that triggers a response in the rabbit rather than the sound. The light emitted by the flash will get to the rabbit instantly (speed of light obviously), but the bullet has to accelerate from stationary and build up speed as it passes through the barrel and is then decelerating, albeit fractionally, as it makes its way to the target. That is a surprisingly slow process. The bullet reaches maximum velocity in the barrel, before any possible flash becomes visible

 

It is not just a matter of taking the distance from the rifle to the rabbit and calculating the time for sound to travel over that distance (as you have done). You also have to factor in the relatively slow burn of the charge and the acceleration of the bullet out of the chamber....the noise (what little there is of it with a .22lr sub) almost exclusively comes out of the barrel, after the bullet has exited.

 

Have you ever watched the men with their antique black powder guns? The delay between applying the "fuse", the powder igniting, building up pressure and finally ejecting the lead ball is quite extraordinary. You could go for a stroll round the park waiting for these, but we are talking about .22lr subs

 

A quick look on the internet suggests that a typical reaction time in a human being is about 160 milliseconds for a sound stimulus. For example hear a sound and in consequence press a button. That is much slower than a reflex action. How do you fancy standing in front of a .22lr sub and testing the theory?

 

Hawke Chairgun Pro suggests that a subsonic bullet takes about 200 milliseconds to travel 60 yards and if you factor in the time after the bang and flash that the bullet takes to leave the rifle it will be even longer. As before, the vast majority of the bang and flash is after the bullet has left the barrel.

 

 

I contend that leaves plenty of time for a rabbit to react, even based on conscious reaction times in a human being where the nerve stimulation has further to travel, rather than the faster reflex response that a rabbit may exhibit...so why don't they all react, or are we talking about a mutant super rabbit here?

 

Coffee anyone.....? How are you getting on with that pot?

 

Edited June 29, 2013 by Dekers

[walt1980]

I'd get a pot!

👍👍

[dadioles]

I have had coffee now - best in South Cambridgeshire. If ever you are in the area Dekers pop in for one of my brews.

 

After a bit of a poke around on the net it seems as though what I have described is known as the "startle response" and research with rats has shown that there is only a 10 millisecond latency which is pretty amazing.

 

If an animal can react to a sound in only 10 milliseconds and it takes 200 milliseconds for a bullet to travel 60 yards or so, why do you have a problem accepting that, from time to time, a rabbit may react to the sound of a gun being fired at it and move slightly before the bullet strikes. Dropping its head one inch is all that it would take for a missed headshot although there may be room for earings.

 

I do wish that people would not keep describing the moderated .22lr as "virtually silent". It is not. Maybe their hearing is in a very poor state. Compared to an unmoderated .22lr it is very quiet, similar to a moderated air rifle. But certainly NOT almost silent.

A rabbit will hear the tiniest sound of a gun being cocked let alone being fired. What do you think those big sticky out things on the top of its head are for?

 

It seems that to cover 60 yards, very approximately, an air rifle pellet takes 300 milliseconds, a subsonic .22lr 200 milliseconds, an hmr 100 milliseconds.

[Deiseboy]

 

What's a subsonic crack?

It was obviously a typo

[Dougy]

Are 22lr silent when dry fired

 

(sorry another silly comment from me. But hey!!!)

 

NO they aint, so why would firing a bullet that needs a small amount of powder and lets not forget a little bit of lead styphnate to start it all in motion make it even quieter.

 

You can moderate the noise from a 17HMR muzzle better by using mod different than a Sak.

[Dekers]

I have had coffee now - best in South Cambridgeshire. If ever you are in the area Dekers pop in for one of my brews.

 

After a bit of a poke around on the net it seems as though what I have described is known as the "startle response" and research with rats has shown that there is only a 10 millisecond latency which is pretty amazing.

 

If an animal can react to a sound in only 10 milliseconds and it takes 200 milliseconds for a bullet to travel 60 yards or so, why do you have a problem accepting that, from time to time, a rabbit may react to the sound of a gun being fired at it and move slightly before the bullet strikes. Dropping its head one inch is all that it would take for a missed headshot although there may be room for earings.

 

I do wish that people would not keep describing the moderated .22lr as "virtually silent". It is not. Maybe their hearing is in a very poor state. Compared to an unmoderated .22lr it is very quiet, similar to a moderated air rifle. But certainly NOT almost silent.

A rabbit will hear the tiniest sound of a gun being cocked let alone being fired. What do you think those big sticky out things on the top of its head are for?

 

It seems that to cover 60 yards, very approximately, an air rifle pellet takes 300 milliseconds, a subsonic .22lr 200 milliseconds, an hmr 100 milliseconds.

 

Cambridge is my home town.....maybe one day...

 

I'm in Norwich on 8 July for the day, bit of a trip from Reading and I guess it would take me somewhere close(ish) to you, but no time then for anything but work, that will be a long old day!

 

I don't know about a rabbits reaction time, but I know a rabbit isn't a rat.

 

Time wise we are not talking about the time the bullet takes, we are talking about the "difference" between the time the bullet takes and the speed of sound!

 

If anyone can come up with a rabbits reaction time we may get somewhere, as we know the speed of sound and we know the speed of various sub sonic ammo, so its simple maths!

 

Like I said before though, anyone who believes this to be true please form an orderly queue to test the theory with live fire aimed at your head!

Edited June 30, 2013 by Dekers

[snipers eye]

Dekers,

The custom moderator is not a very expensive build, it's only cost me £65 which is not a great deal for full stainless steel .

I would love to give a full db report but I have only got a mk1 ear but I will give a honest opinion and pictures.

 

Paul

hi paul.i am waiting with interest for your results

[Traztaz]

You all seem to be missing a point. As I first pointed out its a flinch thing. 1 make bunny aware you are there, lamp, cycle bolt, take off safety, rest rifle on hood, what ever it is that makes that small thing that makes him aware and there is starts with the odd bunny that flinches to the shot. I am in no way saying they can hear and react to a bullet coming, its just the other things you did. As faras the sub sonic goes it might be the pulling of the trigger they hear , who knows, but sure as hell some get lucky with a flinch.

[Traztaz]

OH and for the guy making his own mod, if you like send me the original mod and yours and I will test them for you. Like I said at the beginning of this Mod development is what I do and have thousands of pounds worth of kit to measure the real results of what they do.

[Dekers]

You all seem to be missing a point. As I first pointed out its a flinch thing. 1 make bunny aware you are there, lamp, cycle bolt, take off safety, rest rifle on hood, what ever it is that makes that small thing that makes him aware and there is starts with the odd bunny that flinches to the shot. I am in no way saying they can hear and react to a bullet coming, its just the other things you did. As faras the sub sonic goes it might be the pulling of the trigger they hear , who knows, but sure as hell some get lucky with a flinch.

 

Precisely!

[snipers eye]

Jeffo,

moderating firearms is an interesting science, but the basics are this.

Subsonic ammo can be made through the use of a moderator virtually silent.

Standard ammo, will make a bang,most center fire rifles produce between 150 and 165 Db, this is loud and will damage your unprotected hearing.The HMR also comes into this bracket. A moderators job for these types of caliber is to bring the Db level down to an acceptable , ie non damaging to the hearing of the shooter, level.This means moderating the peak level of sound to less than 137Db, its still quite a bang. Some moderators will get you as low as about 125Db, but more than that without subsonic ammo you can forget.

Any further questions please feel free to ask as I develop and test moderators for a living.

Scott

hi there scot,with all your available equipment,and experience,can you tell me what is the name of the moderator that brings the hmr down to125db,?thanks