Good question! It’s a very old rule-of-thumb that has the right dimensions and works in practice. The side-on BC thing is a bit of a red-herring, I think. It’s intuitively correct that the side-on BC value would make a difference but then, thinking about it some, the exposed profile of a projectile is basically a cylinder that has a dreadful Ballistic coefficient. So poor, in fact, that variations in the profile fail to make it much worse – or better. The side-on BC is therefore basically a constant regardless of the profile.
… but all of this is supposition – I’ll see it I can find a better answer and maybe post the answer here.
ATB
Dave
"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former." Albert Einstein.
Wouldnt know, Terry and I live in the real world so it wont have been a factor, but how ever high his altitude his projectile weights were wrong too so hes probably all theory and uses some one elses chart instead of actualy bothering to see if its correct (and in a lot of cases its miles out)
Ben
Ah...."Bigtime"
Funny name. Funny man.
Hmmm let's analyse the facts. Bloke in Oz nobody's met makes some outlandish claims. Some of the countries top shooters poo poo them.
Who would YOU believe?
oops. Silly me. You did say...
I despair at some of the people on here, if he said he could fly you'd all be jumping out of windows.
Let those who have a brain look at his claims. I'll spell them out for you.
1. 1" group at 150 yards with 27ft/lbs. (no contradiction from me)
2. Ability to hit a 1" target at 150 yards by judging the wind (requires +/- .25mph). Ha ha
3. Shot (plenty / a lot can't remember exactly) rabbits at OVER 100 yards with an eliminator and NEVER missed one and NEVER required a second shot. HA HA HA HA HA
Anybody who believes points 2 & 3 is either "slow" or has never shot.
Perhaps, if a few could open THEIR minds, you could look at Harry's posting style.
If you were in the pub and a bloke said - just off to the shops in my Porsche you'd laugh at him. Who cares if he has a porsche. In the braggart box. If you heard a bloke say "I'm just off to see my Consultant Neurologist daughter", you'd wince and think he's an attention seeker. Enter Harry. His words.
Put it all together and what do you get? "sniff sniff". Bullseet on yer shoe
In fairness though, it does give a leader to those who can't shoot too well, are jealous of those that can, and have a chance to shout loud.
Here's a simple challenge - put up or shut up. I have a grand that says says nobody on here can get remotely close to what Harry has claimed. There's 20,000 members or so. Top shots. I'll give you odds of 5-1.
Any takers?
Gary,
I wouldnlt have thought it was possible to get a 2 inch group at a 100 yards, but sniper -wolf did and a 10 shot group( sub 12 ft.lbs)
Perhaps Harry is one of those chaps with a unique ability?
Harrys energys at 150 yards were more than Terry and I got at 100 yards and we had 3 ft lbs more at the muzzle with the same JSB pellet as Harry(27 v 30)
Harrys 4000 ft of elevation will not make more than a few % difference to anything I wouldnt think, hence my disbalief on all fronts.
Ben
I was asking you to publish the data so we could see where you made the mistake. How * exactly * did you measure the energy at 100 yards? What BC value was assumed? How was it corrected for ambient temperature/pressure/altitude?
Ah, so this disbelief is based on your intuition. Perhaps if you actually did the sums as to the difference that 4000 Ft of elevation makes you could view the data a little more objectively.
ATB
Dave
"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former." Albert Einstein.
gary a few people on here have done some long range shooting with pcp and springers and the results speak for themselfs you maybee able to call harry a liar(as you say noboday has witness it from england) but can you call the other people on here WHO have posted there results with pictures liars i think not maybee you can not shot at 100 yrds plus yourself with decent accuracy but others seem to be able to do it even with legal limit guns.yes funny name but not a funny man.also why would a leading magazine publish such an article(bare in mind gary these magazine are there to promote are sport now if these claims from harry are not true why would the magazine publish such an article) so if they are not true and a leading magazine writes an article about it how can i belive the tosh you terry and ben are spouting on here.not haveing a dig just stating the obvious.oh by the way i would like to hear nigel allens view on this it can not be hard for mr doe to get him to put a post up in his own words as to why he would publish such a article if not true
yep makes you wonder where all the posts and photos have gone from people on this board to me it looks like if gary/terry/and ben can not do it then it gets deleted or is it that just once gary has bitten of more than he can chew and everything gets deleted just to save face.like i said gary not haveing a dig just stateing the obvious
Originally Posted by Originally Posted by baz
That day it felt to be wind free, my ex was reading ranges off LRF and I first took a marker shot then used aiming mark to aim off as there was a bit of wind, the Rabbits died humanely, the rifle (Ripley XL25) was shooting Bismags just below speed of sound
You are aware both Gary and Terry write for the same airgun magazine publishing company that published Harry's article
I don't really know where that puts opinion, on the one hand the magazines are truthful and honest and on the other Harry's article was a work of fiction?
Hell now even I'm puzzled
Richard
A man can always use more alcohol, tobacco and firearms.
There is no such thing as free speech on this forum, its privately owned and you get to say what is allowed, anything that falls foul of the admins guidelines gets deleted, email Edward if you want