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One for MB , Vics vapour rub
19 February 2018, 18:22,
#11
RE: One for MB , Vics vapour rub
With the sound barrier you either need to be below it or you need to exceed it by a fair margin or accuracy is compromised , .22lr subs are made in most cases to achieve 1065 fps non subsonic factory ammo is usually around 1250 fps , never seen any ammo quoted between these figures I'm lead to believe on poor accuracy grounds
I would expect pellets to be the same.
Nothing is fool proof for a sufficiently talented fool!!!!
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20 February 2018, 06:00,
#12
RE: One for MB , Vics vapour rub
Over here it is not unusual for 22lr ammo to be all over the place, especially when you own a chrono and actually measure a few rounds.

I shoot a lot of Eley and SK ammo and find that it is very consistent, hovering around the 1050 mark you have mentioned. Much of our hi-speed stuff goes faster then the 1250 mentioned. Some approaches 1400-1500fps with the 38 grain bullet.

I also shoot a bit of Fiocchi subsonic which starts out just below 1000fps and shoots a 40 grain bullet.

Federal ammo company came out with a 60 grain sub-sonic load some years back but it will not stabilize in the standard twist barrel. It is specifically made for best energy transfer from suppressed barrels.

There is also the situation where many 22 pistols will not get more than 1000fps from that 1250 rated rifle ammo.

With 22lr the max velocity is usually obtained out of a 13" barrel! That was a shock to me, but true. Some loads even slow down when fired from a longer barrel due to friction.

There is a lot written about ammo becoming unstable when it crosses the sound barrier, but at .22 ranges that is usually not an issue. If it starts below the SB it stays there and if it starts above the SB it is usually going to end its flight before it falls below that speed.

That is one of the limiting range factors for many center-fire rifles. They are accurate out to their trans-SB limit and scatter their groups after that mark, be it 800/1000/1200 meters. That is where ballistic coefficient and other math heavy factors enter the marksmanship craft.

The Enfield .303 is a good example of that. The 175 grain slug has such a solid BC that it carries farther than many rounds that start at higher velocities using 150 grain bullets. The 7x57 Mauser in the military 175 grain load is much the same.
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20 February 2018, 06:05,
#13
RE: One for MB , Vics vapour rub
I doubt crossing the SB makes much difference with .177 pellets either, few will ever make that trip.

The standard shape of the air rifle pellet is not conducive to holding speed during flight. If behaves more like a shotgun slug than a rifle bullet.
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20 February 2018, 08:54,
#14
RE: One for MB , Vics vapour rub
(20 February 2018, 06:05)Mortblanc Wrote: I doubt crossing the SB makes much difference with .177 pellets either, few will ever make that trip.

The standard shape of the air rifle pellet is not conducive to holding speed during flight. If behaves more like a shotgun slug than a rifle bullet.

Tumbling in flight is very much a problem with skirted pellets.

My experience is that lighter, and therefore faster pellets group badly compared to their heavier, slower cousins. This is particularly noticeable when comparing ( theoretical ) +1000fps against sub 800fps

But increased power from dieseling just makes noise, smoke and inaccuracy. I agree with MB: to despatch a wounded critter, a big stick would probably be most effective
72 de

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STATUS: Bugged-In at the Bug-Out
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20 February 2018, 20:54,
#15
RE: One for MB , Vics vapour rub
I wouldn't use a souped up air rifle either but it was the only possible use I could come up with , was thinking of cage type traps where you could poke the barrel through specifically so a priest would be no use.
Nothing is fool proof for a sufficiently talented fool!!!!
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20 February 2018, 21:03,
#16
RE: One for MB , Vics vapour rub
I was told the optimum barrel length was between 14 and 16 inches for .22lr
, the subsonic are rated at 1050-1065 fps , standard s are usually advertised as around 1250 fps then there's the hypervelocity up around 1400 to 1650 fps which I have never found a brand of the hypers that held any kind of group , I also have had the 60 grain subsonic , mine were aguilla sss snipers , they were a very long bullet in a .22short case , they were terrible in feeding and in accuracy.
Nothing is fool proof for a sufficiently talented fool!!!!
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20 February 2018, 21:21,
#17
RE: One for MB , Vics vapour rub
Now that is one situation where I would advocate the use of a catapult launching an arrow before I would use an air gun.

And if you are controlling pests that is one thing, if you are fetching food home in a survival situation another.

Unless you have an audience made up of animal rights activists you can always just poke a hole in the critter with a sharp stick and let it bleed out.

As for the use of air rifles, even the weak ones legally allowed, I am not all crazy-ways against their use. Just their misuse, and the unrealistic expectations many have of them since "that is all we have so it will just have to do!".

I have found from long difficult experience that things do not always work just because they "have too".

But, if you want to make a meal from pidgins, robins, ground squirrels or other plump critters of about that size they are dandy devices.

My FIL, long dead these 20 years, was born in 1920 and a young boy when the Great Depression hit. He was also partly orphaned due to his father dying when he was 5, leaving his mother with five kids to feed when there were no social services to lean upon.

He told the story of many meals made up from a mess of robins killed with the Daisy air rifle, or often a catapult and pebbles if there was not a penny available for a pack of B-Bs.

Forage hunting and fishing kept the family alive for 15 years.
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23 February 2018, 22:06,
#18
RE: One for MB , Vics vapour rub
I learnt my lesson regarding dieseling a long time ago . I ended up with a bulged compression chamber on a very very nice Webley mk3 . And though I do believe 12ft lb’s is more than adequate for our domestic small game of kept under sensible ranges . If I ever wanted more power I’d just switch to an air rifle with more swept volume . The power gained by dieseling Is vastly outweighed by erratic shot consistency . You can have more power , it means bugger all
If you can’t ensure consistet groups . Shot placement will always trump power when we’re talking small calibre’s and equally small projectile expansion .
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23 February 2018, 22:40,
#19
RE: One for MB , Vics vapour rub
I would second MB on his recommendation of a catapult or "bean flip."

Easily home-made, using the fork from an apple or other suitably shaped tree branch, surgical grade rubber tubing, the tongue of an old shoe and either braided nylon fishing line or dental floss. SG buckshot or 10mm steel ball bearings are very effective on rabbit-sized game, and with practice you can shoot accurately to 10-15 metres.

My boyhood example is used for whacking bears out of the vegetable garden.


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73 de KE4SKY
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