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Wsm

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Everything posted by Wsm

  1. Its all to do with being in the trade,having something to sell and how much advertising you want to do
  2. Just goes to show that once you've found a blank that suits your rifle stick to it.I was lucky and found a factory blank that was so good it even beat the fabled "one hole group"
  3. Which mod were you using Matt and did it tighten your blank group ?
  4. Wsm

    218 BEE

    Theres nothing like a polite introduction for your first post on the site is there
  5. Not from us as we're on invision
  6. From Brown Dog LONG RANGE SHOTS AND FIRST ROUND HIT PROBABILITY The Error Budget’ Grouping ability at a given range is just one element of the issues to consider when attempting to guarantee first round hits . What's actually critical is realistic quantification of the distance between the POA and the probable POI of your first bullet. That distance is determined by a raft of variables known as the error budget. The error budget in gunnery is extensive. Each element will affect the shooters capability to place his first shot near his POA: Crosswind error Rangewind error Ranging error Weapon cant Weapon pointing error MV variance Round dispersion Air Temp Change Air Density variation Angle of fire Horizontal zeroing error Vertical zeroing error Sight resolution Optical Path Bending I shan’t consider each in detail, but it's worth observing that changing light conditions alone (ie Optical Path Bending or refraction) can move the POI vertically 0.5MOA (or left or right for a low sun). Hit Probability and Error Discs’ Many sporting shooters fail to understand the error budget at play in hit probability and are unable to distinguish their hit probability from their ability to group. Be clear: In shots at sporting quarry we are not talking about grouping theory or ability; we must concern ourselves with the theory of hit probability’. As soon as you've fired your first "adjusting round" at a target you've directly measured the environmental effects; and can adjust subsequent shots accordingly…but we're not in that business with shots at game animals; the first round must have an acceptably high probability of killing humanely …- and thus first round hit probability has to be assessed realistically. Lets say a 0.5MOA grouper at 100yds (many people mistakenly believe the group size-range relationship is linear, it is not.) prints his 0.5moa group half an inch off dead-nuts centre of his POA. His outermost round could be 0.75MOA from his POA. That's an error radius of 0.75MOA. His circular error actually subtends twice that: 1.5MOA. So, in hit probability terms, this 0.5MOA shooter actually has a circular hit probability that subtends 1.5 MOA -doesn't sound quite so cool does it? At game animals we're in the business of guarantee; so let's round that 1.5moa to 2 moa to give ourselves an additional 0.25moa fudge factor around the tgt to allow for those 0.75moa group days Thus, at a range the shooter can achieve 0.5MOA groups, his unadjusted hit probability actually spans a 2MOA disc over any given POA -before we consider wind! Taking this eg to an A4 size kill zone at 400yds; firstly the disc only just fits, and secondly; you can't move it much laterally until it comes off the sheets: about 3.5"” …..so you'd have to know your wind call is accurate to better than 3.5" of deflection to take that shot. My Rifle Groups to 0.5MOA at 400yds, So I'm Good-to-Go with stalking shots at 400yds. Right? You should now realise that considering your first round capability to be 0.25 MOA around your POA; because you can usually group to 0.5MOA is unrealistic in 'guarantee' terms. Grouping ability is a measure of the rifle, not the shooter-rifle system's”ability to make first round hits under field conditions. Once you consider the 'system' it is rarely realistic to guarantee field accuracy better than within 1 MOA of POA (ie a 2 MOA circle); and, at deer, we're talking 'guarantee' ….. and remember, 2 MOA is a guarantee level of within 1 MOA of POA, not "sometimes I can do 0.5MOA with my rifle at 400m on a no-wind range day". How far is Too Far’? As outlined earlier, a clever way of applying hit probability theory quickly is to visualise the killzone (as say, a piece of A4 in Landscape) and place your POA 1MOA in from the windward edge (ie even if the wind ceases, you still guarantee a kill-hit within your 2MOA system guarantee -in effect you are visualising drawing your 2MOA guarantee as a circle disc and fitting it inside the leading edge of the A4 sheet). Then determine go/no go by calculating how much wind will take any part of your 2moa 'guarantee disc' out of the leeward edge of the A4 sheet -and deciding whether you have the wind more accurately than that all the way to the target. Pretty soon you'll realise that it's not a 'strong gust' that'll mess things up; hunting at long range it's as little as being out by a few mph on your wind call; or not noticing a wind change of only a few mph. In order to quantify this, think of wind in terms of "inches of deflection per 1 mph change". For example; a 308 at 400yds: A 10mph wind will push the bullet around 14” at 400yds. This means every 1mph change pushes the bullet 1.4 inches at 400yds. So Even if you are capable of grouping with a 308 to 0.0001MOA at 400 yds (and you won't be), for every 1 mph you misjudge the wind, you will miss your POA by 1.4 inches . Miss a 5mph wind change and your bullet goes 7 inches wide of the aiming point. Miss a 10mph change and you’re 14 inches wide. ...and that's forgetting the natural dispersion of your group compounding the error. In Closing: If an individual considers their deflection-per-mph-wind-change at a distance they're considering; add that to their error disc at that range and then compare that to the size of the animal's kill zone, they should quickly get an idea of what their max range should be, based on their wind reading capability. And if anyone is claiming first round wind reading guaranteed better than to the nearest 5-10mph over unknown and broken ground they're ...err.... kidding themself. It doesn't take much to get blown out of an animal's kill zone.
  7. Before posting please remember the duty that we owe to our quarry,whatever species,the minimum of suffering.A long range shot on a Varmint the size of a rabbit/corvid invariably ends up with either a hit or miss.In most cases any sort of hit will either kill the quarry or at least render it immobile for a swift follow up shot. Its been widely discussed on here that such shots on larger species do not carry anywhere near the amount of certainty of either of the two outcomes and although we know that we can make mistakes at shorter ranges the opportunity to rectify matters is far greater the nearer we are to the target Andrew Venables,a vastly experienced deer manager,owner of the WMS Ranges and long range instructor recommends to "avoid shooting unwounded animals over 200 yards,300 if you are really good and practice a lot" Our very own Brown Dog has produced the following piece regarding First Shot Hit Probability at long range here http://ukvarminting.com/forums/index.php?s...0#entry68599 You must decide the circumstance of your own shot and act accordingly and we are not telling anyone at what range they should be shooting larger beasts but if this is your bag ok then please respect the owners wishes and don't post them on here Thanks Admin
  8. Spud If you e-mail the picture to Mcmillan they`ll tell you the exact percentages (usually quite quickly) I`d be interested to know about the tan stock myself
  9. Thanks Martin A comprehensive guide thats now been made a sticky
  10. Posted before somewhere but here are two of mine Green 80% Black 20% Grey 20% Black White Grey 1/3 each That Olive Tan Black does look the business doesn`t it
  11. Anyone advertising syndicate places on this site must include the following information : Rough Area Acreage New or existing syndicate Number of members Private or Commercial letting Species on ground Cull numbers past & expected Price We can appreciate that advertising places is usually done with the best intentions and including the above will go somewhat to protecting both the site and individual members Below is a list of questions that prospective members should be asking any sellers if interested(by PM please)
  12. Duey You are correct in hindsight I should have not said running out of steam but should have said dropping more than the shooter was aware at that range as you pointed out Apologies for the confusion
  13. Dwight It could be that or that the bullet is simply running out of steam at that range if its spot on at 100yds If you look at Federal ballistic charts the 243 100g bullet drops around 6" to the 250 mark It`s probably best to put up some targets at various ranges to work out the drops. If the bullet is unstable at longer ranges you`ll see the keyholing
  14. Jerry A couple of links that will explain it far better than I could http://www.gunnersden.com/index.htm.rifle-...wist-rates.html And http://www.chuckhawks.com/rifle_barrel.htm
  15. It seems bizarre that such an obscure calibre should be offered in a factory configuration does it not.Blazer also offer it in their listings After looking on the ammo guide it apparently gives ballistics similar to the 6mm-06 and is based on a 9.3x62 case
  16. Three of the biggest manufacturers (Remmy,Sako,Tikka) and a good few others give their standard twist rate for a 243 at 1:10 Still the biggest factory stalking round sold in the UK is the 100 grain so you`d think that they stabilize well enough in the majority of these rifles I`m glad you cleared up the Heym twist rate question though.Makes you wonder why some one selling a product wouldn`t take the time to find out the basics of what they`re offering
  17. Harry Do you have a link to this?The reason I ask is that when I looked at them a few years back the importer at the time informed me they were 1:10 Why don`t you think that twist rate wouldn`t stabilize well with 100 grainers ?
  18. I`m pretty sure you`ll find its 1:10 and if so yes
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