Airgun World – Summer 2019

8 AIRGUN WORLD http://www.airgunshooting.co.uk

THE AIRGUN WORLD FORUM FOR YOUR RANTS, RAVES AND Q&As

POINTS OF YOU

Thanks to the generosity of the people at Jack Pyke, we’re

able to give away a pair of the brand new Hunters boots every

month to the reader we consider to have sent the best letter.

That’s 120 quid’s worth of excellent footwear, just for letting

us know what’s on your mind. You’ve got to like those

numbers!

So, have a think about what you want to say and get in

touch, by email or letter. Don’t write pages of text because

we’ll have to edit it and we’d rather your thoughts were

just as you wrote them. State shoe size and address, and it’s

great if you can include a photo, too. I promise we read every

communication we get.

If your letter wins, you’ll get these superb boots, which

feature full grain leather uppers, a Vibram Trek Hunter

rubber sole, a 100% waterproof, breathable, Hydroguard

membrane, odour-resistant Agion antimicrobial inners

and Thinsulate liners.

They’re great boots - so good luck!

During the recent General Licence debacle, I was really at a loss

about how to protect the wrens that always nest in our garden

hedge. Normally, I’m on permanent patrol once the wrens’ eggs

hatch, and I shoot magpies as they work their way through the

hedge, looking to take the chicks. This year, though, I had to stand

down my Air Arms S510 until I was sure about the legalities, so I

came up with another method. All I did was enclose the section of

the hedge that contained the wrens’ nest with chicken wire, the

mesh of which was large enough to allow the wrens in and out, but

too small for magpies and crows. The wrens didn’t give the mesh a

second thought, and it did its job perfectly. The young wrens have

fledged, now, but I’m going to leave the mesh in place

and allow the hedge to grow through it, making it a permanent,

invisible barrier to corvids, and a sanctuary for ‘our’ wrens.

I’m pleased the General Licence issue has now been resolved and

I have my ‘direct control’ option back, but the ‘sanctuary’ is always

on duty, so something good came out of all that nonsense after all.

Keep up the good work!

TONY BARON

What a fantastic solution, Tony, and well done for not allowing

something beyond your control to affect your conservation duties!

Please accept a fine pair of Jack Pyke boots to help you on those

patrols. All the best. - Ed

LETTER OF THE MONTH WINS THE JACK PYKE HUNTERS BOOTS

TECHNICAL INTEREST

Every month, I read the

Technical Airgun pages with

great interest and the July

issue was no exception. Jim

explained in fascinating

detail all aspects of yaw and

its effect on trajectory and

stability. He also said that

on a molecular level, the

surface of a pellet

resembles a mountain

range. It seems to me that

this would cause a

spinning pellet to curve in

the direction of the spin,

very much like the hook

or slice on a golf ball is

caused by side spin, or curve on a football when curled into the top corner

of the net. One side of the ball is travelling in the direction of the spin and so has less or negative

drag, whilst the other side is moving against the spin with the resulting increase in drag, the net result

being curve on the ball.

However, this does not appear to be a factor when applied to spinning pellets, otherwise especially

when shooting in a cross wind, drift would be far more pronounced depending on which direction

one was shooting. This doesn’t seem to be the case. I wonder if Jim has the answer.

JOHN RYAN

Jim Tyler replies: You are quite correct, John. Spin drift is a very real phenomenon, although the

amount by which the pellet drifts at normal airgun ranges and pellet velocities is so small (typically

less than a pellet width at 50 yards) that it would be difficult to measure in real-world conditions, and

very few will ever be aware of it.

The ever-fascinating world of pellet flight is

appreciated by reader, John Ryan.

MORE PELLET POSERS

Any object moving through a fluid

has a boundary layer, just like a

pellet moving through the air. Many

shooters inspect the pellets for the

smallest irregularities. Since all

pellets have imperfections, how

large would the imperfections have

to be before it affects the flight path

and therefore accuracy? How about

the effect of velocity on the

boundary layer and flight path?

SKIP

Jim Tyler replies: As far as pellet

imperfections and accuracy go, it’s

a matter of degree. A level of

accuracy that might satisfy a less

demanding shooter, for instance,

could be wholly unacceptable for

bench rest, and each will assess

individual pellets according to their

needs.

The question about the

relationship between velocity, the

boundary layer and accuracy is one

that needs to be answered by a

professional ballistician, which, as I

hope I made clear in the article, I

am not. However, I think I know

someone who can help and I’ll

revisit the ‘imperfections’ subject

when and if I gather sufficient data.