Anyone shooting .20 cal here?

[BackStop]

I've got a Veteran in .22 @ right under 20fpe. JSB 13.43.

I've got a USFT in.177 @ right under 20fpe. Jsb 10.34

I'll soon have a Raptor in .20 that can be setup for right under 20fpe.  JSB 13.73.

I know the first two are very accurate. Travis's vids sure make a compelling argument for the .20 as well. 

I'll wait for a nice windy day and shoot groups with all three to see how much wind drift each caliber experiences. With three very accurate guns at the same power but different caliber, should be interesting.

The most fair comparison will be between the Veteran and the Raptor as pellet weights will be very close there. They also both have traditionally rifled barrels. The .177 in the mix shoots best with 10.34gr and has a poly barrel so it won't quite be apples to apples. Still should be fun and possibly informative.

Look forward to seeing your results.   Even if the .20 does better against the wind, I will still be curious as to why?   If .20 caliber is truly better than .22 and .177, there has to be some definitive reason.

Good luck and thanks!

[Motorhead]

Think about blowing up a balloon.   You have to have volume, not just pressure.

That is an interesting thought; that the added volume in the base of the blown out pellet is enough to drop the system pressure.  I was thinking the same thing; except that the added volume was the pellet having moved pellet length down the barrel.

That said, if the valve closed with the pellet 25% down the barrel VS 50%, surely in both cases the pellet saw the same peak pressure; when the pellet was right close to the breech?

Generally an incorrect assumption they see equal pressure ...

Reason for is this in part,  The pellet will break free and start moving down barrel at far lower pressure than what the regulator, valve releases etc ...
The acceleration of the pellet happens in a very short distance and this is tied to PRESSURE pure and simple ( This we can agree upon )  Trick is a word some may not be familiar with ... AMPLITUDE. which is the strength and speed in which the pressure builds.   If the valve opens and closes doing so threw smaller ports, the pressure peak is reduced but duration in increased ( Lower amplitude ) If the valve is open and closes for the same period of time using LARGE ports the pressure peak is sudden and intense but has less duration. this would be  ( High Amplitude )

So a pellet subjected to lower & slower rise in pressure ( smaller ports ) it will break free and start moving before peak pressure is able to get behind it. Because valve is open / close in short time span you get what we''ll call a Blow gun effect.  Now take this same event threw BIG ports the pressure rises behind pellet really fast that when the pellet does break free and start moving there is more pressure packed in behind it.  More a cheek slap blow gun effect.


AMPLITUDE of the pressure that gets behind pellet BEFORE IT MOVES will change the pressure within the space between valve and said pellet BECAUSE as pellet starts moving the volume behind it increases exponentially & further it moves away from where it started the pressure pushing upon it is collapsing becoming less and less due too the increasing volume. 

 hope this makes some sense
 

[oldpro]

I've got a Veteran in .22 @ right under 20fpe. JSB 13.43.

I've got a USFT in.177 @ right under 20fpe. Jsb 10.34

I'll soon have a Raptor in .20 that can be setup for right under 20fpe.  JSB 13.73.

I know the first two are very accurate. Travis's vids sure make a compelling argument for the .20 as well. 

I'll wait for a nice windy day and shoot groups with all three to see how much wind drift each caliber experiences. With three very accurate guns at the same power but different caliber, should be interesting.

The most fair comparison will be between the Veteran and the Raptor as pellet weights will be very close there. They also both have traditionally rifled barrels. The .177 in the mix shoots best with 10.34gr and has a poly barrel so it won't quite be apples to apples. Still should be fun and possibly informative.

Look forward to seeing your results.   Even if the .20 does better against the wind, I will still be curious as to why?   If .20 caliber is truly better than .22 and .177, there has to be some definitive reason.

Good luck and thanks!

I can tell you this it shot better at 800 fps with the .20 cal JSB than my Veteran .22 did at 920 with a CZ barrel. shotting the 15 grain JSB thats saying something. Ill post the Raptor video you can see how hard it was blowing and how well it shot at only 800 fps so there is definitely something to the .20 I dont know of just yet but will get down to it.   

[BackStop]

Think about blowing up a balloon.   You have to have volume, not just pressure.

That is an interesting thought; that the added volume in the base of the blown out pellet is enough to drop the system pressure.  I was thinking the same thing; except that the added volume was the pellet having moved pellet length down the barrel.

That said, if the valve closed with the pellet 25% down the barrel VS 50%, surely in both cases the pellet saw the same peak pressure; when the pellet was right close to the breech?

Generally an incorrect assumption they see equal pressure ...

Reason for is this in part,  The pellet will break free and start moving down barrel at far lower pressure than what the regulator, valve releases etc ...
The acceleration of the pellet happens in a very short distance and this is tied to PRESSURE pure and simple ( This we can agree upon )  Trick is a word some may not be familiar with ... AMPLITUDE. which is the strength and speed in which the pressure builds.   If the valve opens and closes doing so threw smaller ports, the pressure peak is reduced but duration in increased ( Lower amplitude ) If the valve is open and closes for the same period of time using LARGE ports the pressure peak is sudden and intense but has less duration. this would be  ( High Amplitude )

So a pellet subjected to lower & slower rise in pressure ( smaller ports ) it will break free and start moving before peak pressure is able to get behind it. Because valve is open / close in short time span you get what we''ll call a Blow gun effect.  Now take this same event threw BIG ports the pressure rises behind pellet really fast that when the pellet does break free and start moving there is more pressure packed in behind it.  More a cheek slap blow gun effect.


AMPLITUDE of the pressure that gets behind pellet BEFORE IT MOVES will change the pressure within the space between valve and said pellet BECAUSE as pellet starts moving the volume behind it increases exponentially & further it moves away from where it started the pressure pushing upon it is collapsing becoming less and less due too the increasing volume. 

 hope this makes some sense

Scott, that makes perfect sense.  I had not even thought about the "blow gun" effect.   However, there still needs to be enough volume of HP air to keep the projectile moving down the barrel.  Right?   Not simply pressure alone?   Otherwise, would the projectile not slow down due to friction?

Thanks!

[oldpro]

 Here at speed 930 fps with the heavy 20 cal JSB 15.89 threw very poor wind conditions as well. It just cheats the wind somehow. Like i said I dont know why but it does.
 

[oldpro]

Think about blowing up a balloon.   You have to have volume, not just pressure.

That is an interesting thought; that the added volume in the base of the blown out pellet is enough to drop the system pressure.  I was thinking the same thing; except that the added volume was the pellet having moved pellet length down the barrel.

That said, if the valve closed with the pellet 25% down the barrel VS 50%, surely in both cases the pellet saw the same peak pressure; when the pellet was right close to the breech?

Generally an incorrect assumption they see equal pressure ...

Reason for is this in part,  The pellet will break free and start moving down barrel at far lower pressure than what the regulator, valve releases etc ...
The acceleration of the pellet happens in a very short distance and this is tied to PRESSURE pure and simple ( This we can agree upon )  Trick is a word some may not be familiar with ... AMPLITUDE. which is the strength and speed in which the pressure builds.   If the valve opens and closes doing so threw smaller ports, the pressure peak is reduced but duration in increased ( Lower amplitude ) If the valve is open and closes for the same period of time using LARGE ports the pressure peak is sudden and intense but has less duration. this would be  ( High Amplitude )

So a pellet subjected to lower & slower rise in pressure ( smaller ports ) it will break free and start moving before peak pressure is able to get behind it. Because valve is open / close in short time span you get what we''ll call a Blow gun effect.  Now take this same event threw BIG ports the pressure rises behind pellet really fast that when the pellet does break free and start moving there is more pressure packed in behind it.  More a cheek slap blow gun effect.


AMPLITUDE of the pressure that gets behind pellet BEFORE IT MOVES will change the pressure within the space between valve and said pellet BECAUSE as pellet starts moving the volume behind it increases exponentially & further it moves away from where it started the pressure pushing upon it is collapsing becoming less and less due too the increasing volume. 

 hope this makes some sense

Scott, that makes perfect sense.  I had not even thought about the "blow gun" effect.   However, there still needs to be enough volume of HP air to keep the projectile moving down the barrel.  Right?   Not simply pressure alone?   Otherwise, would the projectile not slow down due to friction?

Thanks!

Thats correct Kerry and how I did it was using a big .250 TP and machining a radial 6 TP design barrel thats indexable with 6x .120 ports. So high volume, high amplitude design. Scott really knows his stuff!!!

[BackStop]

Think about blowing up a balloon.   You have to have volume, not just pressure.

That is an interesting thought; that the added volume in the base of the blown out pellet is enough to drop the system pressure.  I was thinking the same thing; except that the added volume was the pellet having moved pellet length down the barrel.

That said, if the valve closed with the pellet 25% down the barrel VS 50%, surely in both cases the pellet saw the same peak pressure; when the pellet was right close to the breech?

Generally an incorrect assumption they see equal pressure ...

Reason for is this in part,  The pellet will break free and start moving down barrel at far lower pressure than what the regulator, valve releases etc ...
The acceleration of the pellet happens in a very short distance and this is tied to PRESSURE pure and simple ( This we can agree upon )  Trick is a word some may not be familiar with ... AMPLITUDE. which is the strength and speed in which the pressure builds.   If the valve opens and closes doing so threw smaller ports, the pressure peak is reduced but duration in increased ( Lower amplitude ) If the valve is open and closes for the same period of time using LARGE ports the pressure peak is sudden and intense but has less duration. this would be  ( High Amplitude )

So a pellet subjected to lower & slower rise in pressure ( smaller ports ) it will break free and start moving before peak pressure is able to get behind it. Because valve is open / close in short time span you get what we''ll call a Blow gun effect.  Now take this same event threw BIG ports the pressure rises behind pellet really fast that when the pellet does break free and start moving there is more pressure packed in behind it.  More a cheek slap blow gun effect.


AMPLITUDE of the pressure that gets behind pellet BEFORE IT MOVES will change the pressure within the space between valve and said pellet BECAUSE as pellet starts moving the volume behind it increases exponentially & further it moves away from where it started the pressure pushing upon it is collapsing becoming less and less due too the increasing volume. 

 hope this makes some sense

Scott, that makes perfect sense.  I had not even thought about the "blow gun" effect.   However, there still needs to be enough volume of HP air to keep the projectile moving down the barrel.  Right?   Not simply pressure alone?   Otherwise, would the projectile not slow down due to friction?

Thanks!

Thats correct Kerry and how I did it was using a big .250 TP and machining a radial 6 TP design barrel thats indexable with 6x .120 ports. So high volume, high amplitude design. Scott really knows his stuff!!!

Thanks Travis.   Slowly I am beginning to understand more and more about all of this stuff.  (grin)

However, most of the really technical jargon goes right over my head and makes it hurt!  (chuckle)

Edit:
Come to think of it, I shot blow guns when I was young and if you blew only from your mouth and didn't use your diaphragm to pump up the volume, the dart didn't have much velocity.It had to do with the volume of air along with the quick release/intensity of the blow.   So, amplitude I guess.

[Motorhead]

Think about blowing up a balloon.   You have to have volume, not just pressure.

That is an interesting thought; that the added volume in the base of the blown out pellet is enough to drop the system pressure.  I was thinking the same thing; except that the added volume was the pellet having moved pellet length down the barrel.

That said, if the valve closed with the pellet 25% down the barrel VS 50%, surely in both cases the pellet saw the same peak pressure; when the pellet was right close to the breech?

Generally an incorrect assumption they see equal pressure ...

Reason for is this in part,  The pellet will break free and start moving down barrel at far lower pressure than what the regulator, valve releases etc ...
The acceleration of the pellet happens in a very short distance and this is tied to PRESSURE pure and simple ( This we can agree upon )  Trick is a word some may not be familiar with ... AMPLITUDE. which is the strength and speed in which the pressure builds.   If the valve opens and closes doing so threw smaller ports, the pressure peak is reduced but duration in increased ( Lower amplitude ) If the valve is open and closes for the same period of time using LARGE ports the pressure peak is sudden and intense but has less duration. this would be  ( High Amplitude )

So a pellet subjected to lower & slower rise in pressure ( smaller ports ) it will break free and start moving before peak pressure is able to get behind it. Because valve is open / close in short time span you get what we''ll call a Blow gun effect.  Now take this same event threw BIG ports the pressure rises behind pellet really fast that when the pellet does break free and start moving there is more pressure packed in behind it.  More a cheek slap blow gun effect.


AMPLITUDE of the pressure that gets behind pellet BEFORE IT MOVES will change the pressure within the space between valve and said pellet BECAUSE as pellet starts moving the volume behind it increases exponentially & further it moves away from where it started the pressure pushing upon it is collapsing becoming less and less due too the increasing volume. 

 hope this makes some sense

Scott, that makes perfect sense.  I had not even thought about the "blow gun" effect.   However, there still needs to be enough volume of HP air to keep the projectile moving down the barrel.  Right?   Not simply pressure alone?   Otherwise, would the projectile not slow down due to friction?

Thanks!

This is true. But if we go WAY LEFT FIELD and look at spring piston guns where they start out at zero pressure within the compression chamber then when fired PEAK at pressures that can be 2000 PSI added to by heat of the rapid compression, you will understand AMPLITUDE and low volume. Thus why a Spring piston gun has such low muzzle report, energy / pressure created is a so fast to rise it launches the pellet then collapses having very little volume of air exiting behind the pellet at muzzle.  Along with many spring guns have very short barrels ( Side & under cockers ) because more barrel length buys you nothing but drag performance wise.
Longer overshrouds or barrels typically are for easier cocking in barrel breaks or longer sighting distance.
Our highly tuned PCP's are just starting to operate in this manor and why some are so oddly quiet at pretty high out output power.  The SSG devises controlling dwell have played a big part .... as have light hammers and when married to reduced opening / balanced valves we are starting to realize the Amplitude of the shot cycle can pay very large dividends. 

[BackStop]

Think about blowing up a balloon.   You have to have volume, not just pressure.

That is an interesting thought; that the added volume in the base of the blown out pellet is enough to drop the system pressure.  I was thinking the same thing; except that the added volume was the pellet having moved pellet length down the barrel.

That said, if the valve closed with the pellet 25% down the barrel VS 50%, surely in both cases the pellet saw the same peak pressure; when the pellet was right close to the breech?

Generally an incorrect assumption they see equal pressure ...

Reason for is this in part,  The pellet will break free and start moving down barrel at far lower pressure than what the regulator, valve releases etc ...
The acceleration of the pellet happens in a very short distance and this is tied to PRESSURE pure and simple ( This we can agree upon )  Trick is a word some may not be familiar with ... AMPLITUDE. which is the strength and speed in which the pressure builds.   If the valve opens and closes doing so threw smaller ports, the pressure peak is reduced but duration in increased ( Lower amplitude ) If the valve is open and closes for the same period of time using LARGE ports the pressure peak is sudden and intense but has less duration. this would be  ( High Amplitude )

So a pellet subjected to lower & slower rise in pressure ( smaller ports ) it will break free and start moving before peak pressure is able to get behind it. Because valve is open / close in short time span you get what we''ll call a Blow gun effect.  Now take this same event threw BIG ports the pressure rises behind pellet really fast that when the pellet does break free and start moving there is more pressure packed in behind it.  More a cheek slap blow gun effect.


AMPLITUDE of the pressure that gets behind pellet BEFORE IT MOVES will change the pressure within the space between valve and said pellet BECAUSE as pellet starts moving the volume behind it increases exponentially & further it moves away from where it started the pressure pushing upon it is collapsing becoming less and less due too the increasing volume. 

 hope this makes some sense

Scott, that makes perfect sense.  I had not even thought about the "blow gun" effect.   However, there still needs to be enough volume of HP air to keep the projectile moving down the barrel.  Right?   Not simply pressure alone?   Otherwise, would the projectile not slow down due to friction?

Thanks!

This is true. But if we go WAY LEFT FIELD and look at spring piston guns where they start out at zero pressure within the compression chamber then when fired PEAK at pressures that can be 2000 PSI added to by heat of the rapid compression, you will understand AMPLITUDE and low volume. Thus why a Spring piston gun has such low muzzle report, energy / pressure created is a so fast to rise it launches the pellet then collapses having very little volume of air exiting behind the pellet at muzzle.
Our highly tuned PCP's are just starting to operate in this manor and why some are so oddly quiet at pretty high out output power.  The SSG devises controlling dwell have played a big part .... as have light hammers and when married to reduced opening / balanced valves we are starting to realize the Amplitude of the shot cycle can pay very large dividends.

I only had one NP "springer" and it had SIGNIFICANT muzzle report.   It was really loud.

The volume of air released behind the pellet was substantial.   Of course, this was not a tuned springer, but a tuned springer still needs a certain volume of air to keep the projectile moving down the barrel before friction slows it down.   In a quieter airgun (PCP or springer) it is tuned so that the volume of air is used more efficiently and there is less air behind the pellet when it exits the barrel while keeping it moving without significant loss of velocity.   Of course, there is a trade off in either direction.   Too much volume and the air is wasted and the report is a lot louder.  Too little volume and the pellet actually slows down due to friction before it leaves the barrel, which may not be so bad if the fps is what is needed/wanted.

I shot blow guns when I was younger as I said in an earlier reply, and if you simply used your mouth air to shoot, the dart had little velocity due to little volume of air.   No matter how fast or abruptly you released/blew that air into the blowgun.   Only when you used your diaphragm to increase the volume of air were you able to get the velocity needed.   It really took the entire body to do it effectively.   So it is a combination of "amplitude" and volume of air.   Both are necessary to be effective.

Anyway, I don't think we really disagree for the most part.

[subscriber]

Inquiring minds would like to know if the velocity difference between the two pellets below, included changing transfer port restriction?  Or just hammer strike?  The FPE increase would be 40%, assuming identical pellets.

If only hammer strike, perhaps the valve did not open very wide on the 850 FPS pellet; and was actually acting as a restrictor similar to a TP restrictor, to lower peak pressure behind the pellet, as Motorhead explained.

Odd thing is that I don't think the pressure itself was higher...lower sped was a short "blip" of 3K air, high pseed was a loing "burrrrp" of 3K pressure....so a volume/duration thing rather than a peak pressure thing?

[Ribbonstone]

An old Sumatra 2500PCP...so by the way they did the 'power wheel" adjustment, was a matter of striker stock/valve stem protrusion (able to be hit/driven in my the striker).

Yeah...know it is an odd system...one that the Sumatra's seem to be alone in using,,,it's kind of like a B-Staley O-ring mod (that limits the valve stem rod's "hit length")...but it works..and pretty much changes valve dwell rather than anything else (so the pellets still get 200BAR pressure, just for a little "blip" at lower power rather than a long "phart at high power..

[subscriber]

Interesting.  I wonder of Bob has any wisdom to offer.  Not that this thread hasn't been diverted enough already

[BackStop]

Think about blowing up a balloon.   You have to have volume, not just pressure.

That is an interesting thought; that the added volume in the base of the blown out pellet is enough to drop the system pressure.  I was thinking the same thing; except that the added volume was the pellet having moved pellet length down the barrel.

That said, if the valve closed with the pellet 25% down the barrel VS 50%, surely in both cases the pellet saw the same peak pressure; when the pellet was right close to the breech?

Generally an incorrect assumption they see equal pressure ...

Reason for is this in part,  The pellet will break free and start moving down barrel at far lower pressure than what the regulator, valve releases etc ...
The acceleration of the pellet happens in a very short distance and this is tied to PRESSURE pure and simple ( This we can agree upon )  Trick is a word some may not be familiar with ... AMPLITUDE. which is the strength and speed in which the pressure builds.   If the valve opens and closes doing so threw smaller ports, the pressure peak is reduced but duration in increased ( Lower amplitude ) If the valve is open and closes for the same period of time using LARGE ports the pressure peak is sudden and intense but has less duration. this would be  ( High Amplitude )

So a pellet subjected to lower & slower rise in pressure ( smaller ports ) it will break free and start moving before peak pressure is able to get behind it. Because valve is open / close in short time span you get what we''ll call a Blow gun effect.  Now take this same event threw BIG ports the pressure rises behind pellet really fast that when the pellet does break free and start moving there is more pressure packed in behind it.  More a cheek slap blow gun effect.


AMPLITUDE of the pressure that gets behind pellet BEFORE IT MOVES will change the pressure within the space between valve and said pellet BECAUSE as pellet starts moving the volume behind it increases exponentially & further it moves away from where it started the pressure pushing upon it is collapsing becoming less and less due too the increasing volume. 

 hope this makes some sense

Scott, that makes perfect sense.  I had not even thought about the "blow gun" effect.   However, there still needs to be enough volume of HP air to keep the projectile moving down the barrel.  Right?   Not simply pressure alone?   Otherwise, would the projectile not slow down due to friction?

Thanks!

This is true. But if we go WAY LEFT FIELD and look at spring piston guns where they start out at zero pressure within the compression chamber then when fired PEAK at pressures that can be 2000 PSI added to by heat of the rapid compression, you will understand AMPLITUDE and low volume. Thus why a Spring piston gun has such low muzzle report, energy / pressure created is a so fast to rise it launches the pellet then collapses having very little volume of air exiting behind the pellet at muzzle.
Our highly tuned PCP's are just starting to operate in this manor and why some are so oddly quiet at pretty high out output power.  The SSG devises controlling dwell have played a big part .... as have light hammers and when married to reduced opening / balanced valves we are starting to realize the Amplitude of the shot cycle can pay very large dividends.

I only had one NP "springer" and it had SIGNIFICANT muzzle report.   It was really loud.

The volume of air released behind the pellet was substantial.   Of course, this was not a tuned springer, but a tuned springer still needs a certain volume of air to keep the projectile moving down the barrel before friction slows it down.   In a quieter airgun (PCP or springer) it is tuned so that the volume of air is used more efficiently and there is less air behind the pellet when it exits the barrel while keeping it moving without significant loss of velocity.   Of course, there is a trade off in either direction.   Too much volume and the air is wasted and the report is a lot louder.  Too little volume and the pellet actually slows down due to friction before it leaves the barrel, which may not be so bad if the fps is what is needed/wanted.

I shot blow guns when I was younger as I said in an earlier reply, and if you simply used your mouth air to shoot, the dart had little velocity due to little volume of air.   No matter how fast or abruptly you released/blew that air into the blowgun.   Only when you used your diaphragm to increase the volume of air were you able to get the velocity needed.   It really took the entire body to do it effectively.   So it is a combination of "amplitude" and volume of air.   Both are necessary to be effective.

Anyway, I don't think we really disagree for the most part.

I think I misspoke here.   Amplitude, like amps in electricity, IS the volume.   The pressure is like watts.

100,000 watts can be relatively harmless if the amps are low enough.   Increase the amps (volume) enough and 120 watts can be deadly.

Perhaps the dynamics of air don't work exactly that way, but at least it sounds good.  (grin)

[RichH]

I think I misspoke here.   Amplitude, like amps in electricity, IS the volume.   The pressure is like watts.

100,000 watts can be relatively harmless if the amps are low enough.   Increase the amps (volume) enough and 120 watts can be deadly.

Perhaps the dynamics of air don't work exactly that way, but at least it sounds good.  (grin)

Might want to stop here as you are still "mis-speaking". Replace "watts" with "volts" and you will be a whole lot close to being correct. Power (wattage) is the product of voltage and amperage. W=VxA
Amps are the "volume", but the "pressure" is the voltage.

[Iceman]

If we only had some .20 cal slugs to choose from,that would be great!!

[gendoc]

If we only had some .20 cal slugs to choose from,that would be great!!

+1...

[Franklink]

They're coming.

Nick from NSA has mentioned it a couple times on forum posts, here and AGN.

He also commented the same in a recent video where Dana (Crosman999 I think) went to NSA for a factory tour and Q&A with Nick.

[gendoc]

They're coming.

Nick from NSA has mentioned it a couple times on forum posts, here and AGN.

He also commented the same in a recent video where Dana (Crosman999 I think) went to NSA for a factory tour and Q&A with Nick.

thats great, Nick knows i'm waiting.....

[Ribbonstone]

Use to be a lot of choices in 5mm pellets...this certainly isn't all of them,but what I had on hand.



Most of them we're better off without...eveidently the makers found it profitible for a time, but no one really misses crappy pellets, and only decent 5mm pellets seem to have survived.

Just using PA as a reference...seems to be a chopice of 6 pellets now.  So long as at least one of the 6 shoots well,  who cares?

But If you do go 5mm, I'd buy a lot of pellets while I could...it's a shrinking market, and no airgun is real useful without ammo.

"Down" to 4 5mm's (which is still more than my .25 count). One co2 (HW rebarrel), one springer, two PCP's.



So I guess I like the caliber.  Other than a fondness,really don't see it as "stand alone better".

Can quote ballistics that show it to be "better" than most .177's...or some .22's...but PCP's velocity/power ability kind of changed the equation.

[Motorhead]

If we only had some .20 cal slugs to choose from,that would be great!!

Lets first realize for the time being and past, the .20 caliber is a PELLET caliber.  While over the years there have been a lot more choices in .20 that we don't see today, what we do have today covers the caliber quite well with all ( Except the benjamin) shooting VERY very accurately in most guns.

H&N FTT at 11.4 grains
H&N Crow Magnum at 12.8 grains
JSB Exact at 13.7 grains
H&N Barracuda at 13.6 grains
JSB Exact heavy at 15.9 grains
*While the Sam Yang / Eugun can be found overseas ( Korea ) there at 23.7 grains

Honestly that is not the desert of despair some make it out to be for the lowly .20 cal