PCPs and supersonic pellets

[Lucifer]

look its easy. look at wind tunnles. how do they get air velocities in excess of 14X the speed of sound.

simple let air expand at its fastes rate (around the speed of sound), and then channel this through a cone shaped nozzel. using the correct ratio for the change in dimater, and a high enough starting pressure you can obtain very high speeds.

Its true that the the air temp drops greatly which may affect the spped of sound localy. but as soon as the pellet exits the barrel it is travely through standard temp and pressure. so they can all be ignored.

speeds in excess of 3X speed pf sound can be produced in open ended wind tunnles. so a supersonice air gun could be produced.

Has one been made is another matter, im a sub 12ftlb guy

[David Snook]

All you have to do is post specific chrono readings over 1170 fps and then "certain individuals" will acknowledge the fact.

Lionel

Lionel

I am happy to oblige, please find an extract from an advertising broadsheet for various velocity and energy levels on the new Beaumont air rifle based on the Air Ranger/RWS 500:

.22 - 75 ft/lbs. 30,5gr. Pellet in excess 1050 ft/s. (5,50mm.)
.22 - 90 ft/lbs. 30,5gr. Pellet in excess 1150 ft/s. (5,50mm.)
.22 -100 ft/lbs. 40,0gr. Pellet in excess 1050 ft/s. (5,70mm.)
.25 -130 ft/lbs. 50,0gr. Pellet in excess 1100 ft/s. (6,35mm.)
.25 -120 ft/lbs. 36,0gr. Pellet in excess 1200 ft/s. (6,35mm.)
.30 -175 ft/lbs. 110 gr. Pellet in excess 850 ft/s. (7,80mm.)

I understand that the velocities are the minimum specified for a string of shots where the velocity will increase over the series before falling due to the power curve. Over 1300ft/s has been recorded with 36 grain .25 ammunition.

This gun has been developed for Export markets and for longer range shooting. Accuracies of 25mm groups are acheived at 150 metre ranges. Alfred the gun's developer reports that these accuracies are generally better than achieved by firearms.

Regards

David

[Baldie]

Lionel

.22 - 75 ft/lbs. 30,5gr. Pellet in excess 1050 ft/s. (5,50mm.)
.22 - 90 ft/lbs. 30,5gr. Pellet in excess 1150 ft/s. (5,50mm.)
.22 -100 ft/lbs. 40,0gr. Pellet in excess 1050 ft/s. (5,70mm.)
.25 -130 ft/lbs. 50,0gr. Pellet in excess 1100 ft/s. (6,35mm.)
.25 -120 ft/lbs. 36,0gr. Pellet in excess 1200 ft/s. (6,35mm.)
.30 -175 ft/lbs. 110 gr. Pellet in excess 850 ft/s. (7,80mm.)

This gun has been developed for Export markets and for longer range shooting. Accuracies of 25mm groups are acheived at 150 metre ranges. Alfred the gun's developer reports that these accuracies are generally better than acheived by firearms.

Regards

David

So not only do we pay 'top money' for our products here in the UK, we don't get the benefits of the technology developed here either. I'd be happy to own an air rifle with these levels of power/accuracy over these ranges. Safer than rimfire too?

Why 'export only'? Or is this a dumb question given the 'unofficial' 40ft/lb limit on FAC air rifles?

[pneuguy]

...this particular claim is not, unless the rifle in question runs at very (VERY ) high pressure, or has an extraordinarly long barrel.

Lionel

...Over 1300ft/s has been recorded with 36 grain .25 ammunition.

It would require an average breech pressure in the neighborhood of 4500psi (310bar) to achieve "over 1300fps" with so heavy a pellet in .25 with any normal bore length.

That's assuming, of course, that we're talking about ordinary air - and not a lower molecular weight gas like helium - as the propellant.

Small typo, perhaps?

Steve

[David Snook]

Steve

You might well be right, unless I have made a mistake. I know that Alfred has been experimenting with Helium and that is where the high velocity might of come from - I will check.

However all the other velocities listed are achieved with air and are conservative estimates.

David

[Baldie]

Steve

You might well be right, unless I have made a mistake. I know that Alfred has been experimenting with Helium and that is where the high velocity might of come from - I will check.

However all the other velocities listed are achieved with air and are conservative estimates.

David

There is a typo in the calibre sizes, certainly.

Anyway David, answer to my query? Please?

[David Snook]

Baldie

From the start the high power version was only destined for Export, however I do not know what Daystate or RWS intentions are right now.

Certainly introducing these guns into the UK would raise eyebrows, maybe Daystate do not want to attract any more airgun legislation in today's political climate.

Looking at the performance figures I would guess that the accurate range of 150 metres and more that these guns produce would be cause for concern. I know that these guns are being considered for "Eco Friendly" Police and Military sniper training in Europe.

No doubt a call to RWS or Daystate would answer your question Baldie.

David

PS Well spotted, unless it is an "odd" calibre!

[Baldie]

Thanks David.

Awaiting return call..... Shame I wasn't 5 seconds faster with the phone.

Mindful the ricochet problem with rimfire, I'd have thought this technological solution would have been ideal? Accurate, powerful. Even Eco-friendly?

Either available only with 'good cause'? All seems a bit odd to me.

[Baldie]

Had a very interesting and informative telephone conversation with Mr Tony Belas of Daystate.

In a nutshell, the RWS 500 isn't the Air Ranger, though it might look like it. Since it isn't Daystate who are marketing the Ranger, it's not up to them where it gets sold.....

Technically there is a need to use a solid 'slug' (aka bullet) when going above 50-60ft/lbs so it's easy to see where direct comparisons with rimfire start to be made with licensing authorities, and problems might start. [And maybe best avoided].

Seems there's plenty of demand in the US, so might be quite a while before anyone gets the opportunity to import one back to the UK. Think the delivered price will mount up to around a £1000 which is a lot of money for a rimfire equivalent.

Except it seems to be better than an an 'out-of-the-box' rimfire. Much better.

Hmmm. I'd like one. Pricey, but I'd say worth it.

[Beer Hunter]

Other than the novelty factor, I don’t really see the point of these. If the rifle uses a solid bullet fired at up to 1200 fps, you have the same problems with ricochet as a .22 RF and probably a lot more noise.
The laws in other countries are possibly different and may allow air guns of this power where RF is hard to get.

[Baldie]

If the rifle uses a solid bullet fired at up to 1200 fps, you have the same problems with ricochet as a .22 RF and probably a lot more noise.

The laws in other countries are possibly different and may allow air guns of this power where RF is hard to get.

Point 'one' is true.

Point 'two' is currently true in my experience, as no-one is currently aware of an air rifle that'll successfully fire solid ammo, are they? In some respects this technology may eventually define another class of firearm.

My interest lies with the "25mm group" at 150m. If this rifle has a 'volume control', it'll do the work of 3 rifles. FAC air, rimfire, and to a degree, 17 HMR. Or are there 'out-of-the-box' .22 rimfires that'll do 25mm groups at 150m?

[Beer Hunter]

I think the groups at 150m are largely academic. The drop at this distance would be around 25”.

[mikebike]

Technically there is a need to use a solid 'slug' (aka bullet) when going above 50-60ft/lbs

I use both waisted pellets and solid bullets in my Stealth.
The pellets seem to be more efficient and they deliver around 115 fpe, while the bullets reach 110 fpe.

The bullets are purchased from Pyramidair and they weigh 80.4 gr, the pellets are Dae Sung 80gr and they actually weigh 77.5 gr.

Pellet


Regarding FAC, my Stealth is on a "rimfire FAC"! Which means that I can hunt bigger game compared to having an "airgun FAC"

[Shed tuner]

FAC air (even with a mod) is so much louder than a rimfire above about 40 FP, I can't see the point myserlf, except to exploit certain countries' firearms laws on airpowered guns.

[mikebike]

FAC air (even with a mod) is so much louder than a rimfire above about 40 FP, I can't see the point myserlf, except to exploit certain countries' firearms laws on airpowered guns.

No, that's not true. It depends on the "barrel volume". If the barrel is long and/or of a bigger calibre, the rifle is not very loud.
My 9mm /20" Stealth is as noisy as a 22LR without the shroud and very quiet with the shroud on. However, the sound of the hammer hitting the breech is a bit loud.

The major drawback of using a 9mm airgun instead of a RF is ammunition cost!
The pellets cost about 6 times as much as 22LR rounds!