Calculating shot energy..

[Stonepark]

Up in Lochinver so will by necessity be brief (internet speed) is it not the done thing to acknowledge the source of someone else's work?

 

I don't have a note of whose it is or where it came from, just the 1 page

[wymberley]

I don't have a note of whose it is or where it came from, just the 1 page

The table along with a similar one for duck and geese together with a brief explanation were posted for the benefit of members who might have been interested in one of the pinned threads above. I have no recollection of deliberately deleting the copies from photo bucket and it might be suffice to say that they disappeared at the same time that Windows 10 decided to upload itself on to my computer. Either way, they're no longer there. If anyone is interested, I can re-post these when I get home.

 

As the originator, these tables were not posted elsewhere.

Edited September 14, 2016 by wymberley

[TONY R]

I have just done some practical tests on some 410s. I set a target board at a measured 35yrds. Then I soaked newsprint in water until fully saturated and then compressed it until it was 3/4 inch thick. My idea being that this well represented the breast meat of cock/pheasant etc.

I then fired a shot of each size and examined the results. My home load non toxic ITX 6s ploughed through and buried themselves a pellet depth in the hard ply backing. Lylevale fibre 5s patterned well but only about 50% of the shot made it all the way through the paper.

Eley Bismuth did well and all but a couple of the shots made it through and stopped at the ply backing. One can assume that the performance would be better still at the shorter ranges.

You can read all sorts of detail in issued charts but in my view you need to walk the walk and devise something which will give a definitive result and I think this wet newsprint goes a long way to doing that.

I think you on the right track with the wet paper penatration tests, physical tests like this can throw up suprises sometimes velocity is an eye opener on such tests, the theory and the practice although relative are not always cut and dried in the real world.

I like balistics programe data its not bad for evaluation and if you have the real downrange speed you can see the variations on paper and then play it out with your wet paper tests and draw a verey accurate conclusion.

Here is a table some might find interesting on goose shot which shows the often quoted but not perfect 600FPS on target rule for steel shot in a few sizes BB steel being the definition here.

 

[dougall]

I notice the penetration table shows larger shot going deeper....this defies my simple logic that a small bit of shot surely has less resistance and should penetrate further?..a .177 pellet goes clean through a rat,when a .22 does not.....I admit a .177 pellet is travelling faster but to exaggerate the argument if I punched you with a dart in my hand it would go through your skin,If I punched you with a knitting needle it would'nt or at least not as far.....I breast pigeons these days but used to always pluck etc..never knowingly could tell penetration differences between shot sizes have only ever used 5-7.5s on pigeon...I do now go for the pattern wins argument on pigeon hence preference toward 7s,with bigger birds ie Pheasant certainly good strong late/higher ones the extra 'oomph' of 5s does work better...I would 'nt use 7s on January birds..but of course a pigeon is what about 25% the weight of a cock pheasant so bigger hits make sense and at 45-50 yards 7s struggle to cleanly bring down a pheasant,but early season pheasant and partridge 7s are perfect..I guess 1 inch into a pigeon is enough whereas 1 inch into a pheasant breast does not get through to anything 'vital'...

[ElvisThePelvis]

In my view this comes down to mass and therefore energy rather than diameter slowing entry at impact. I take the point about pattern, time to pattern a few cartridges...

[motty]

Diameter of shot has to be taken into consideration. A pellet that doesn't penetrate has less lethal qualities.

[neutron619]

I notice the penetration table shows larger shot going deeper....this defies my simple logic that a small bit of shot surely has less resistance and should penetrate further?

 

The mathematics are simple.

 

Formula for the frontal area of a sphere is A = 2πr².

 

Formula for the mass of a sphere is the volume multiplied by the density, or M = 4/3πr³ρ

 

We're looking at the ratio between the frontal surface area and mass (and via the mass, the pellet energy, but for simplicity we're assuming a constant velocity) for a fixed increase or decrease of the radius "r".

 

We can find the ratio between the two properties by dividing the formulae: for every increase of 1 "unit" of r, the mass will increase by 2/3rρ "units".

 

Essentially this means that for any pellet made of a substance with a density greater than 0.6666666 kg/m³ (basically anything except for the very lightest gases - pellets made of hydrogen, anyone?), increasing the radius of the pellet linearly will result in a greater relative increase in mass.

 

Putting the numbers in for a #7 pellet at 600fps:

 

ρ = 11340kg/m³ (Pure Lead - I'm ignorning any Sb content)

r = 0.0012m (#7 UK = 2.4mm diameter = 1.2mm radius)

 

A = 2 * π * 0.0012² = 9.04779E-6m²

M = (4 / 3) * π * 0.0012³ * 11340 = 8.20815E-5kg

Ratio of (M / A) = 8.20815E-5kg / 9.04779E-6m² = 9.072kg/m²

 

Now for a #5 pellet:

 

ρ = 11340kg/m³

r = 0.0028m (#5 UK = 2.8mm diameter = 1.4mm radius)

 

A = 2 * π * 0.0014² = 1.2315E-5m²

M = (4 / 3) * π * 0.0014³ * 11340 = 0.000130342kg

Ratio of (M / A) = 0.000130342kg / 1.2315E-5m² = 10.584kg/m²

 

Assuming an impact velocity of 600fps:

 

v = 182.88 m/s = 600fps

E = ½mv²

 

E[#7] = 0.5 * 8.20815E-5kg * (182.88²) = 1.373J (c. 1.0ftlbs)

 

E[#5] = 0.5 * 0.000130342kg * (182.88²) = 2.17J (c. 1.6ftlbs)

 

Which means that for a 16% increase in pellet size you receive a 58% increase in striking energy. Further, as we can see from the mass / area ratios, that energy is delivered in relatively more concentrated fashion.

 

To conclude, larger pellets should penetrate better because they have a greater mass to surface area ratio and higher striking energy - assuming the impact velocities are the same.

 

What these calculations cannot account for is travel within the quarry, though they can be considered a guide. In the case of the .177 pellet versus the .22 pellet, I would suspect that the velocity plays a large part, as does pellet geometry. Those effects are much more difficult to calculate when you aren't modelling - as I have above - spheres of different sizes.

 

Edit: Removed an exponent which shouldn't have been included.

Edited September 16, 2016 by neutron619

[ElvisThePelvis]

Diameter of shot has to be taken into consideration. A pellet that doesn't penetrate has less lethal qualities.

 

 

Agreed, i should have clarified that I had pheasant in mind more than anything and the above shows 5 penetrating better than 6, and having more energy, my concern is now pattern and if that's OK in 28g no5 then happy days.

 

Of course the real issue is me getting over excited and making errors, but all things being equal i want to give every chance of a clean kill.

[TONY R]

 

The mathematics are simple.

 

Formula for the frontal area of a sphere is A = 2πr².

 

Formula for the mass of a sphere is the volume multiplied by the density, or M = 4/3πr³ρ

 

We're looking at the ratio between the frontal surface area and mass (and via the mass, the pellet energy, but for simplicity we're assuming a constant velocity) for a fixed increase or decrease of the radius "r".

 

We can find the ratio between the two properties by dividing the formulae: for every increase of 1 "unit" of r, the mass will increase by 2/3rρ "units".

 

Essentially this means that for any pellet made of a substance with a density greater than 0.6666666 kg/m³ (basically anything except for the very lightest gases - pellets made of hydrogen, anyone?), increasing the radius of the pellet linearly will result in a greater relative increase in mass.

 

Putting the numbers in for a #7 pellet at 600fps:

 

ρ = 11340kg/m³ (Pure Lead - I'm ignorning any Sb content)

r = 0.0012m (#7 UK = 2.4mm diameter = 1.2mm radius)

 

A = 2 * π * 0.0012² = 9.04779E-6m²

M = (4 / 3) * π * 0.0012³ * 11340 = 8.20815E-5kg

Ratio of (M / A) = 8.20815E-5kg / 9.04779E-6m² = 9.072kg/m²

 

Now for a #5 pellet:

 

ρ = 11340kg/m³

r = 0.0028m (#5 UK = 2.8mm diameter = 1.4mm radius)

 

A = 2 * π * 0.0014² = 1.2315E-5m²

M = (4 / 3) * π * 0.0014³ * 11340 = 0.000130342kg

Ratio of (M / A) = 0.000130342kg / 1.2315E-5m² = 10.584kg/m²

 

Assuming an impact velocity of 600fps:

 

v = 182.88 m/s = 600fps

E = ½mv²

 

E[#7] = 0.5 * 8.20815E-5kg * (182.88²) = 1.373J (c. 1.0ftlbs)

 

E[#5] = 0.5 * 0.000130342E-5kg * (182.88²) = 2.17J (c. 1.6ftlbs)

 

Which means that for a 16% increase in pellet size you receive a 58% increase in striking energy. Further, as we can see from the mass / area ratios, that energy is delivered in relatively more concentrated fashion.

 

To conclude, larger pellets should penetrate better because they have a greater mass to surface area ratio and higher striking energy - assuming the impact velocities are the same.

 

What these calculations cannot account for is travel within the quarry, though they can be considered a guide. In the case of the .177 pellet versus the .22 pellet, I would suspect that the velocity plays a large part, as does pellet geometry. Those effects are much more difficult to calculate when you aren't modelling - as I have above - spheres of different sizes.

Neutron i am not A level maths material, Bit i tried to understand with wymberley is these models how can you callculate the speed a pellet is traveling at any range past a few feet over the chrono?

If i get a 1550fps BBB load of steel downrange what FPs will it be doing ?

Say 50 yards for example, how can mass air resistance etc be callculated into the model reliably mathermaticaly.

Lowerey and Toasty of the KPY programe utilised ohler equiptment data with winchester backing it i heard, meassuring accuratly the speed is what we just cant do physicaly with gear like chronos etc.

Can you work it out mathamaticaly or make a model up from data from KPY to help ?

[neutron619]

Tony,

It's possible to calculate a pellet's likely velocity at any point out of the barrel if you know the conditions and to do so with a reasonable degree of accuracy.

Although I've been regularly censured on this forum for "spending too much time in front of my computer and not enough time out shooting", I actually wrote a software library 18 months ago to do exactly these sorts of calculations, knowing that some of us were interested in this sort of thing.

The features of the library broadly agree with other available software solutions (i.e. JBM Ballistics) across a range of models and - helpfully - also with reality. Like most of my other programming projects, it's basically functionally-complete, but awaiting publication: writing formal documentation and supporting end users is extremely time consuming and I can't manage that on top of other commitments at present.

Certain features of the library are exposed through the CFSA website at https://www.cfsa.co.uk/ but what can be presented there is necessarily limited by constraints of a web-based interface.

The calculation of trajectories / properties of a shotgun pellet isn't much different to the calculation of the trajectory of a rifle bullet, except that you're dealing with idealized spheres rather than a pointed cylinder (or simillar). Broadly, there are five main considerations.

The first thing you need is an accurate model of the environment in which you're modelling projectile flight. The degree to which this is complicated depends on whether you're calculating the properties from first principles (i.e. molecular mass of air molecules and degrees of freedom of those molecules derive, via the ideal gas law, the partial pressures of each fraction at a given temperature, giving an overall pressure at a given altitude under a certain gravitational force and ultimately, the density of the medium) or whether you simply stick in the density of air being 1.225kg/m³ and go from there. The software library does the former, which would make it possible to calculate projectile flight on Mars, or anywhere, really, if one was so inclined.

The second thing you need is a means of describing the environment's resistance to the motion a particular projectile. A chap called McCoy did some very interesting work on how to estimate the drag coefficient of a projectile of a given shape in the 1970's and wrote a computer model which could predict the ballistic coefficients of a projectile if you describe, mathematically, its geometry.

My library includes McCoy's formulae and will calculate them, but it's actually much easier to take experimental data and interpolate drag coefficients for a standard projectile from experimental data, then adjust for the projectile of interest according to a known ballistic coefficient defined in terms of the standard projectile for a particular velocity. Rifle shooters often use the G1 and G7 ballistic coefficients for their calculations - my library supports all of the Gavre functions and employs them, including the GS / GS1929 functions which are the drag functions for a spherical projectile.

The major difficulty in using drag functions to model projectile motion is that function which calculates the drag force for a given projectile changes according to the projectile's velocity. This leads to the third major consideration - one has to approximate the integration required by the equations of motion for the calculation of a projectile's position and velocity by dividing its trajectory into many tiny sections with respect to time. Essentially, you ask, "how far and how fast has the projectile moved 0.0001 seconds from the origin?" Then, "how far and how fast has the projectile moved in the time between 0.0001 seconds from the origin and 0.0002 seconds from the origin?" and so on. Provided the interval at which you calculate the values is small enough, the approximation should be good (e.g. small enough to make no practical difference).

The fourth consideration is that the model of the projectile must be reasonably accurate. When you're dealing with pellets, you're dealing with projectiles with a relatively tiny mass and low momentum for which drag is highly significant. Because of the behaviour of the GS drag functions, even relatively tiny inaccuracies in pellet size or density can lead to quite different behaviour, particularly in the transonic region. It's therefore best to start from a pellet radius and a material density, much as I have above - the advantage of this approach is that I could tell you the likely behaviour of a 2-gauge gun shooting ping-pong balls with a bit of time to set it up.

The final consideration is that the assumptions you make to be able to actually do the calculations (rather than die in a ditch trying) have to be small enough not to influence the overall result. Working out what's important takes a bit of gut feeling and experimentation. A 1 celsius environmental temperature rise is usually sigificant - certainly for rifle bullet modelling; assuming that the density of a 98% lead / 2% antimony pellet is uniform throughout a shotgun pellet is a sensible approximation that avoids having to calculate individual pellet oscillations due to non-uniform density; defining the initial vector of the pellets in terms of a normally-distributed pattern density is an unavoidable deviation from reality because it's essentially impossible to calculate the deformation (and subsequent behaviour) of individual pellets within the confines of the barrel on generally available hardware - even if I could do the maths.

In the end, you can get a picture that is good enough. It'll never be perfect and I'd never claim that it was (and never have) but I would think that you could rely on most of what's produced by my software and other equivalents to be accurate to within a few fps either way, provided - and this is the important bit - that you enter the parameters of the model accurately and that the model is implemented correctly.

If you want to talk more about what my software can do, send me a PM and I'll get back to you when I can.

Adam.

Edited September 15, 2016 by neutron619

[dougall]

 

The mathematics are simple.

 

Formula for the frontal area of a sphere is A = 2πr².

 

Formula for the mass of a sphere is the volume multiplied by the density, or M = 4/3πr³ρ

 

We're looking at the ratio between the frontal surface area and mass (and via the mass, the pellet energy, but for simplicity we're assuming a constant velocity) for a fixed increase or decrease of the radius "r".

 

We can find the ratio between the two properties by dividing the formulae: for every increase of 1 "unit" of r, the mass will increase by 2/3rρ "units".

 

Essentially this means that for any pellet made of a substance with a density greater than 0.6666666 kg/m³ (basically anything except for the very lightest gases - pellets made of hydrogen, anyone?), increasing the radius of the pellet linearly will result in a greater relative increase in mass.

 

Putting the numbers in for a #7 pellet at 600fps:

 

ρ = 11340kg/m³ (Pure Lead - I'm ignorning any Sb content)

r = 0.0012m (#7 UK = 2.4mm diameter = 1.2mm radius)

 

A = 2 * π * 0.0012² = 9.04779E-6m²

M = (4 / 3) * π * 0.0012³ * 11340 = 8.20815E-5kg

Ratio of (M / A) = 8.20815E-5kg / 9.04779E-6m² = 9.072kg/m²

 

Now for a #5 pellet:

 

ρ = 11340kg/m³

r = 0.0028m (#5 UK = 2.8mm diameter = 1.4mm radius)

 

A = 2 * π * 0.0014² = 1.2315E-5m²

M = (4 / 3) * π * 0.0014³ * 11340 = 0.000130342kg

Ratio of (M / A) = 0.000130342kg / 1.2315E-5m² = 10.584kg/m²

 

Assuming an impact velocity of 600fps:

 

v = 182.88 m/s = 600fps

E = ½mv²

 

E[#7] = 0.5 * 8.20815E-5kg * (182.88²) = 1.373J (c. 1.0ftlbs)

 

E[#5] = 0.5 * 0.000130342E-5kg * (182.88²) = 2.17J (c. 1.6ftlbs)

 

Which means that for a 16% increase in pellet size you receive a 58% increase in striking energy. Further, as we can see from the mass / area ratios, that energy is delivered in relatively more concentrated fashion.

 

To conclude, larger pellets should penetrate better because they have a greater mass to surface area ratio and higher striking energy - assuming the impact velocities are the same.

 

What these calculations cannot account for is travel within the quarry, though they can be considered a guide. In the case of the .177 pellet versus the .22 pellet, I would suspect that the velocity plays a large part, as does pellet geometry. Those effects are much more difficult to calculate when you aren't modelling - as I have above - spheres of different sizes.

I think thats a thanks from me......!.

[neutron619]

I think thats a thanks from me......!.

 

*hat tip*

[TONY R]

Tony,

 

It's possible to calculate a pellet's likely velocity at any point out of the barrel if you know the conditions and to do so with a reasonable degree of accuracy.

 

Although I've been regularly censured on this forum for "spending too much time in front of my computer and not enough time out shooting", I actually wrote a software library 18 months ago to do exactly these sorts of calculations, knowing that some of us were interested in this sort of thing.

 

The features of the library broadly agree with other available software solutions (i.e. JBM Ballistics) across a range of models and - helpfully - also with reality. Like most of my other programming projects, it's basically functionally-complete, but awaiting publication: writing formal documentation and supporting end users is extremely time consuming and I can't manage that on top of other commitments at present.

 

Certain features of the library are exposed through the CFSA website at https://www.cfsa.co.uk/ but what can be presented there is necessarily limited by constraints of a web-based interface.

 

The calculation of trajectories / properties of a shotgun pellet isn't much different to the calculation of the trajectory of a rifle bullet, except that you're dealing with idealized spheres rather than a pointed cylinder (or simillar). Broadly, there are five main considerations.

 

The first thing you need is an accurate model of the environment in which you're modelling projectile flight. The degree to which this is complicated depends on whether you're calculating the properties from first principles (i.e. molecular mass of air molecules and degrees of freedom of those molecules derive, via the ideal gas law, the partial pressures of each fraction at a given temperature, giving an overall pressure at a given altitude under a certain gravitational force and ultimately, the density of the medium) or whether you simply stick in the density of air being 1.225kg/m³ and go from there. The software library does the former, which would make it possible to calculate projectile flight on Mars, or anywhere, really, if one was so inclined.

 

The second thing you need is a means of describing the environment's resistance to the motion a particular projectile. A chap called McCoy did some very interesting work on how to estimate the drag coefficient of a projectile of a given shape in the 1970's and wrote a computer model which could predict the ballistic coefficients of a projectile if you describe, mathematically, its geometry.

 

My library includes McCoy's formulae and will calculate them, but it's actually much easier to take experimental data and interpolate drag coefficients for a standard projectile from experimental data, then adjust for the projectile of interest according to a known ballistic coefficient defined in terms of the standard projectile for a particular velocity. Rifle shooters often use the G1 and G7 ballistic coefficients for their calculations - my library supports all of the Gavre functions and employs them, including the GS / GS1929 functions which are the drag functions for a spherical projectile.

 

The major difficulty in using drag functions to model projectile motion is that function which calculates the drag force for a given projectile changes according to the projectile's velocity. This leads to the third major consideration - one has to approximate the integration required by the equations of motion for the calculation of a projectile's position and velocity by dividing its trajectory into many tiny sections with respect to time. Essentially, you ask, "how far and how fast has the projectile moved 0.0001 seconds from the origin?" Then, "how far and how fast has the projectile moved in the time between 0.0001 seconds from the origin and 0.0002 seconds from the origin?" and so on. Provided the interval at which you calculate the values is small enough, the approximation should be good (e.g. small enough to make no practical difference).

 

The fourth consideration is that the model of the projectile must be reasonably accurate. When you're dealing with pellets, you're dealing with projectiles with a relatively tiny mass and low momentum for which drag is highly significant. Because of the behaviour of the GS drag functions, even relatively tiny inaccuracies in pellet size or density can lead to quite different behaviour, particularly in the transonic region. It's therefore best to start from a pellet radius and a material density, much as I have above - the advantage of this approach is that I could tell you the likely behaviour of a 2-gauge gun shooting ping-pong balls with a bit of time to set it up.

 

The final consideration is that the assumptions you make to be able to actually do the calculations (rather than die in a ditch trying) have to be small enough not to influence the overall result. Working out what's important takes a bit of gut feeling and experimentation. A 1 celsius environmental temperature rise is usually sigificant - certainly for rifle bullet modelling; assuming that the density of a 98% lead / 2% antimony pellet is uniform throughout a shotgun pellet is a sensible approximation that avoids having to calculate individual pellet oscillations due to non-uniform density; defining the initial vector of the pellets in terms of a normally-distributed pattern density is an unavoidable deviation from reality because it's essentially impossible to calculate the deformation (and subsequent behaviour) of individual pellets within the confines of the barrel on generally available hardware - even if I could do the maths.

 

In the end, you can get a picture that is good enough. It'll never be perfect and I'd never claim that it was (and never have) but I would think that you could rely on most of what's produced by my software and other equivalents to be accurate to within a few fps either way, provided - and this is the important bit - that you enter the parameters of the model accurately and that the model is implemented correctly.

 

If you want to talk more about what my software can do, send me a PM and I'll get back to you when I can.

 

Adam.

You can never spend too much time on research, being informed and harnessing this info and applying it to your sport offers potential advantages and a real confidence builder none of this should ever be underestimated.

[ElvisThePelvis]

Guys, this is brilliant, thanks. I'm now really looking forward to patterning next weekend

[wymberley]

Neutron i am not A level maths material, Bit i tried to understand with wymberley is these models how can you callculate the speed a pellet is traveling at any range past a few feet over the chrono?

If i get a 1550fps BBB load of steel downrange what FPs will it be doing ?

Say 50 yards for example, how can mass air resistance etc be callculated into the model reliably mathermaticaly.

Lowerey and Toasty of the KPY programe utilised ohler equiptment data with winchester backing it i heard, meassuring accuratly the speed is what we just cant do physicaly with gear like chronos etc.

Can you work it out mathamaticaly or make a model up from data from KPY to help ?

Assuming BBB is 0.19" and 61 pellets/oz, then c756 ft/sec and 9.1 ft/lbs.

 

Am back home so if anyone would like the tables replacing, just sing out.

[TONY R]

Assuming BBB is 0.19" and 61 pellets/oz, then c756 ft/sec and 9.1 ft/lbs.

 

Am back home so if anyone would like the tables replacing, just sing out.

I am impressed ill gdet a yank to run it through KPy see how that compares.

Now big favour would you be so terribly kind as to provide me well us on here with the formulae to work out these numbers ,

In order and in my case in such a way that even i cant get it wrong.

Is it just a case of punching the chronoed numbers in a calculator and at the end we got a result or is it more complicated than that?

If you can help here i for one would be happy and i dare say so would some more here too.

[wymberley]

I am impressed ill gdet a yank to run it through KPy see how that compares.

Now big favour would you be so terribly kind as to provide me well us on here with the formulae to work out these numbers ,

In order and in my case in such a way that even i cant get it wrong.

Is it just a case of punching the chronoed numbers in a calculator and at the end we got a result or is it more complicated than that?

If you can help here i for one would be happy and i dare say so would some more here too.

For all practical purposes, there's nothing difficult about this. Accurate and proven science together with research is essential as without it, we'd know nowt but for we shooters, it pays to keep it simple. The reasons are legion - who can accurately judge range to within 5 yards at some 50+? - + or - 100 ft/sec or more at the muzzle is totally irrelevant down range - unlike a home loading rifle shooter who uses a chrono and knows exactly what his standard deviation is, does anyone actually know - or has measured - that for their favourite brand of cartridge? In view of this, a reasonably accurate guide to performance suffices and which, in any case, is no more than what the tables published actually achieve.

For example, the table quoted above (as the missing notes indicated) was simply for comparison purposes for anyone wishing to try steel instead of lead shot ( gladly, no so important now). Anyone happy shooting the quarry named at a maximum given distance with a given shot size could simply note the penetration for that combination with lead and pick the same level for steel shot which could then be fine tuned in the field if necessary.

I simply use a Sierra Infinity Suite ballistic programme - which was initially acquired for rifle reloading. With this, however, you do need to know the BC of the pellets - simply using the G1 figure throughout the velocity range is close enough for my purposes. The formula(ae) for penetration is/are readily available on t'net but just make sure the correction factor for pellet boundary layer effect is included (better known, perhaps, as a fiddle factor as without it the results are inaccurate).

[propercartridges]

take out a pocket full of different carts with same load and shot sizes get yourself away to tescos and buy some packets off 500 sheets fax paper put them up at your desired range and shoot them when you do the shot walk and count how many pages you have penetrated till you come to hard indented paper where it has not torn or holed say 67 pages shoot all your desisered carts the same way to give them a fair test then go and find something to shoot at but at all times try to take out the human element which is you then you decide its all i do my 32 gram at a measured 40 yards through half choke break sheets up to 65 pages which is if you nip them altogether a good eight of an inch so it should kill anything if you hit them right i think its a fair test thanks george

[wymberley]

take out a pocket full of different carts with same load and shot sizes get yourself away to tescos and buy some packets off 500 sheets fax paper put them up at your desired range and shoot them when you do the shot walk and count how many pages you have penetrated till you come to hard indented paper where it has not torn or holed say 67 pages shoot all your desisered carts the same way to give them a fair test then go and find something to shoot at but at all times try to take out the human element which is you then you decide its all i do my 32 gram at a measured 40 yards through half choke break sheets up to 65 pages which is if you nip them altogether a good eight of an inch so it should kill anything if you hit them right i think its a fair test thanks george

At one time the cheaper option was the telephone directory but they're so thin now that any shot would probably pass straight through them.