Eric Cortina on setting the dies for shoulder bump

[Rich4]

A spring is hard, when metal softens it becomes malleable, soft, ductile, as it work hardens it will regain its elastic property’s

[bruce moulds]

maybe learn to read conditions as the higher priority.
bruce.

How do you learn that without an accurate rifle?
The Chicken or the Egg?

rich
i think i have learned more about the wind from shooting black powder long range with iron sights than anything.
twice the deflection of a 308 palma load
have to wipe the barrel every shot.
nowhere to run, nowhere to hide.
bruce.

[Tim L]

Bruce, i have to echo Rich4, how does a shooter improve wind reading with an inaccurate rifle?
I agree with your general thinking but if you need to improve your wind reading how do you know you made a wrong call rather than the wide shot being the rifle?

[Tim L]

Rich4,
What are springs made from?
Why are ammo cases made from brass?

[bruce moulds]

tim and rich,
i quite understand your point.
bruce.

[wsftr]

what is an inaccurate rifle? .5moa, .75moa, 1 moa more? In the context of being able to read wind...

[AlanF]

what is an inaccurate rifle? .5moa, .75moa, 1 moa more? In the context of being able to read wind...

I think its more about learning to read the wind (over time) than for example during a 10 shot shoot. And I think describing a rifle as having e.g. "1 moa accuracy" can mean very different things to different people. For us its probably more useful to describe accuracy in terms of e.g. "a 90% likelihood of holding the 6 ring for 10 shots in excellent conditions at 1000yd" (let's call that a 6 ring rifle for the purposes of this discussion). In F-Open in Australia, I would consider a 6 ring rifle to be good enough to give enough feedback about the effect of wind, to (over time) learn wind reading to a match winning level. And in rough conditions that is more accuracy than you need. If we're shooting the longs at Rosedale, and the forecast is for 20mph+ wind, then I will deliberately take a 5 ring rifle so as not to waste a good barrel and components, and still get a very good education (read caning ) in shooting rough conditions.

[Gyro]

I reckon LOTS of shooters have accurate rifles. But not many shooters properly understand what it takes to keep the gun shooting well. The setting up is very important and that's basic physics that clearly escapes many ! Having good rests. Having a stiff stock that doesn't "load up" with a bunch of feral stresses when ya touch it wrong. Yes I know that particular opinion is controversial here. Takes a while to sort all this stuff.

I notice that normally a shoot is won or lost at the longs and seems to me many group sizes enlarge at the longs way out of proportion to the conditions ? Because the costly effects of all the incorrect 'simple' stuff is magnified ?

[bruce moulds]

my black powder rifles can shoot 3/4 moa at 100 yds in kind conditions.
what i have leaned about wind effects on vert has been most surprising.
then i found a wind chart in a small book by sir henry halford which predicts BOTH deflection sideways and verticle for a typical 45ish calibre bullet at speeds used.
the magnified effects might be missed with low drag bullets at higher speed.
bruce.

[Tim L]

what is an inaccurate rifle? .5moa, .75moa, 1 moa more? In the context of being able to read wind...

An inaccurate rifle is one that can't shoot groups smaller than the target you want to hit.

[bruce moulds]

or is it one where you can come up 2 clicks, and the first shot after that comes up 2 clicks, and you know for sure you don't have to fire 2 more to verify it.
bruce.

[williada]

A few years back a couple of us did some comparative studies for a handicap system for various classes. Alan's was looked at, Monash Uni Maths Department did modelling and I used another model and all came up with similar results at the same time. The basis for the system I used was grouping ability. I assumed the TR rifle was capable of 1 moa, the FS was capable of 1/2 moa and the FO rifle was capable of 1/4 moa. The rifles I use will all meet these minimum expectations over 10 shots at 150 yards. If beginners can do this at short range then they can expect to do it at longer ranges within reason as groups open a tad at long range, when they master reading conditions. These are what I call accurate rifles and if I do my part with conditions, I expect a perfect score. I don't hope for one. If conditions beat me, I note what I missed to do better next time. Better rifles will of course will increase the x count.

I don't chase shots because I know that the distribution of shots is random within the grouping capability of the rifle unless the wind or light changes. What I do do is safe side shots knowing my grouping capability to improve my score, particularly at 1000 yards. In other words I don't always shoot for X's but want to stay in for score when that matters more. I use shorter ranges to pump out a high x counts which should form from an accurate rifle with the normal distribution of the group. Jim Sweet demonstrates in his book how more shots are lost by chasing shots or chasing the spotter while you are learning. Old but true. Let the group build so your zero or group centring is more precise. Machine gunning is a separate technique and can only be mastered with an accurate rifle.

You have to determine what your rifle will do over a string of shots not just 3 shot groups. At a minimum this is 7 shots for practicing to be statistically relevant, especially for extreme spread assuming load development has been completed.

The other thing to do is learn how to calculate the wind from indicators such as mirage and flags. Write up a range card based on a computer program for your load. Keep it handy and check it between shots while you are learning. When a shot lies outside expectations of group and a reason for change in the conditions is not apparent, I don't alter on the shot but go again to confirm if I missed something or the shot was just pilot error. Rifle cant is a common source of this problem with beginners. Watch for light changes that effect elevation or wind pick ups or drop offs that also effect elevation. The old saying is left wind lowers, right wind raises. So there is a lot to learn about conditions and an accurate rifle will assist in identifying the subtleties of weather to put in the memory bank and progress a beginner's development more quickly.

[bruce moulds]

regarding accuracy, my rifle is currently shooting a bit less than 1/2 moa vert at 300 mt, and right on 1/2 moa at 900.
have yet to try 600.
that will be the test of a good load, as the slow ones might be going higher and the fast ones lower, giving vert in the middle range.
i am using the steam driven method as i can't afford a labradar.
of course horizontal is far greater than vertical.
bruce,

[Tim L]

Using an accurate rifle to learn wind reading.
Sunday was a practice from 900m. A bit blustery from 1/2 to 3 1/2 minutes left to right and slightly butt to mound.. Direction was pretty consistant once the wind was in. I coached the first round on my target and another open shooter had coached his, so we both had a reasonable idea of what was going on.
I had called shots on full wind and had found 'flags up' was worth 3 minutes and up with a tail flutter was 3.5 so called shots on both with the necessary adjustment.
The other shooter had found an identifiable 2 minute point on flags and when I shot we used that. Mirage was 'dirty' (couldn't see the X ring and the 6 was vague) I used the 2.5 minute marks on 55 power, to bracket the aiming mark (NF comp)
He called flags, I watched mirage. Flags were on the right.
This was the 6.5 SLR still shooting well with close to 2000 rounds on it.
1st shot was the 12 oclock X so I came down a click and put 4 more in the X ring. Shot 6 was the 6 at 4 oclock. 7 was an X. Shot 8 I called a change in light but mirage and flags were good so i fired and got the 12 oclock 5. We waited for the light (no adjustment) and shot the 12 oclock 6. For shot 10 I called an increase in mirage speed and we waited a bit but it didn't come up on the flags. We decided to go and pulled the top 4 and no sooner had the score come up when the flags followed!
We decided to see what mirage AND flags were worth so fired a quick follow up for the bottom 4. I cranked on a minute and got the go followed by a hastey "wait" but too late and popped the left 5. I took the minute off and shot the 6 at 10 oclock.
I would say that by using a gun that you know holds 3/4 of an X and not adjusting you can have reasonable confidence in the results.

20201012_083449.jpg

Conclusions.
Light DOES matter on the Townsville range.
Mirage was true (not always the case)
Flags were true (not always the case) but were delayed mid range.
Don't be too keen to release the shot.
The 6.5 SLR is still a very capable barrel.
Could I have pumped out a 60? Highly likely. I would normaly wait for the light. I would normally have waited for the mirage to settle and shot my condition. And I would have learned nothing.
IMO club leader boards and club comps every visit to the range are the worst possible way of improving wind reading.
Anyway, I'm back to my FTR gun. This open stuff is too easy

[Tim L]

Just my thoughts btw. There are many other exercises but they all cost points.