Calibres, How And Why Did They Choose Them?

[Rez 4,957]

P'man clicks his fingers and we all stop pissing about... sit a large circle and listen...

 

Indeed that a post and a half that Simon.

[PeskyWabbits 464]

A good post Simon. Now would Mr Whitworth have decided on .177 or would it have been 4.5 mm? It just seems too coincidental to be imperial then have 5,5 following it.

But thank you for the definition

[PeskyWabbits 464]

Another thing.

Many people don't seem to understand where to put the decimal point.

We are see these funny adverts with 1.77 or 2.2 calibre. Just think how big these pellets would be!

[pianoman 3,586]

I think it would've been devised as .177th of an inch barrel diameter with a specific projectile or bullet calibre of 4.5 mm. The diameter width and the required length of the round. Then weight of the round, energy by weight and so on is factored into the calibre maths.

 

Whitworth was an obsessive perfectionist in everything he did. He wrote everything he did down in his journals which have become the bedrock of many practices in arms manufacture today. He was possibly, the first arms and ammunitions design engineer to have devised what is surely now the forunner of the 17HMR calibre bullet and rifle. But, being an industrialist with his work firmly focused on military applications and requirements for firearms, such a small round was not going to excite either the British Army and Royal Navy, nor the widening African big game safari sporting firearms market who both wanted big, powerful magnum killing rounds for man and beast.

[bigmac 97kt 13,738]

 

"The Photo" has been sent to Rezmond and Chief Shit Stirrer x

 

It sure has mate... Soooooo over the moon with it too...

 

image1.jpeg

 

x

 

REZ YOU FECKING KILL ME AT TIMES LOL

 

ATVBJIMMY :thumbs:

[mark williams 7,549]

Rez / Mac !!!!!

 

 

 

Shhhhhhhh you twats !

 

We`ll get fecking detention

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

" Again"

[philpot 4,931]

Quote

'.25 - might as well throw a brick underarm - awful trajectory.'

 

 

Except when it has 47fpe pushing it along then it has a better trajectory than your sub 12 .177

 

Zero at 25mt-----------1/2 a mildot hold over at 60mt, AA fields 25.4gr, job done

 

Phil

Edited June 20, 2017 by philpot

[mark williams 7,549]

Exactly ! ​ Except when it has 47 fpe ( foot pounds energy) pushing it along, then it has a better trajectory than your SUB 12 .177

 

​The large majority of shooting lads on this forum are using sub 12 ft/lbs rifles and a large majority " assume" we are talking sub 12 ft/lbs rifles but hey totally agree that an "air cannon" like that would give those results.

Useful where field craft cannot be applied, I suppose but I wouldn't like to cook the remnants of a small bird/ rabbit struck like that, unless head shot !

There again .177 at sub 12 will give the same result but a far tidier and more skilful one, with field craft applied or created.

 

Mark.

[philpot 4,931]

Exactly ! ​ Except when it has 47 fpe ( foot pounds energy) pushing it along, then it has a better trajectory than your SUB 12 .177

 

​The large majority of shooting lads on this forum are using sub 12 ft/lbs rifles and a large majority " assume" we are talking sub 12 ft/lbs rifles but hey totally agree that an "air cannon" like that would give those results.

Useful where field craft cannot be applied, I suppose but I wouldn't like to cook the remnants of a small bird/ rabbit struck like that, unless head shot !

There again .177 at sub 12 will give the same result but a far tidier and more skilful one, with field craft applied or created.

 

Mark.

Oh dear Mark, you do make me laugh.

 

Phil

[mark williams 7,549]

I can understand why.