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PostPosted: Fri Jan 30, 2004 12:41 pm 
I think I am going to regret asking this question, but what the hell. Since there seems to be a lot of controversy surrounding the use of lead pellets (personally I think they are fine), and criticisms of some of the substitutes designed to replace them, I feel the need to ask why a top quality all-plastic pellet cannot be made for 10m shooting.
Some of the modern plastics are quite heavy (not as heavy as lead of course) and are, like Delrin, self lubricating. I cannot believe that modern technology could not produce a really top quality prodict if it wanted to.
Any opinions?
Tom
twoodle1-at-bigpond.net.au.48744.0


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PostPosted: Fri Jan 30, 2004 12:53 pm 
The same company (dynamic) that makes the tin pellets makes plastic body pellets as well.
The have a plastic body and a tin head. As a child I had some with the tin head and a steel head, they were ok but there was a tendency for the steel ones to separate from the body like a sabot...and nearly fly sideways. As well the steel head if it hit something hard would bounce around like a BB. Since it was odd shaped it also had a tendency to bonce around like a square ball...which gave no clue as to a direction it might go in. Often times BB's if hitting a surface face on will come right back, these steel cone heads would go any which way.
The other MAIN problem with all these designes is that they are not diablo designs. Airguns have diablo or wasp waisted pellets for a reason, the resistance in the barrel, the air flow over the pellet, the compression of the body on the firing sequence. The "air tunnel" results that the Dynamics use to claim "air superiority" are false for many reasons. The laminar flow over the pelet body, various cross sectional dynamics, yaw, lenght to weight ratios and inertia all play a very important part in why soild body pellets do not work as well. One of the most confounding issues that these pellets come up against is the distribution of their weight in relation to their center of gravity and how that weight defines their center of gravity.
I think in the end to have as good of a performance from a pellet, you need a wasp waisted pellet...until somone comes up with a replacement for lead to make a wasp waisted pellet, there really is no replacement.

.48746.48744


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PostPosted: Fri Jan 30, 2004 3:34 pm 
I didn't know this. Thanks for setting me straight. I should have said in my original question,that I was talking about proper diabolo target pellets. I'm still curious why no firm has attempted to produce such a thing
Regards
Tom

: The same company (dynamic) that makes the tin pellets makes plastic body pellets as well.
: The have a plastic body and a tin head. As a child I had some with the tin head and a steel head, they were ok but there was a tendency for the steel ones to separate from the body like a sabot...and nearly fly sideways. As well the steel head if it hit something hard would bounce around like a BB. Since it was odd shaped it also had a tendency to bonce around like a square ball...which gave no clue as to a direction it might go in. Often times BB's if hitting a surface face on will come right back, these steel cone heads would go any which way.
: The other MAIN problem with all these designes is that they are not diablo designs. Airguns have diablo or wasp waisted pellets for a reason, the resistance in the barrel, the air flow over the pellet, the compression of the body on the firing sequence. The "air tunnel" results that the Dynamics use to claim "air superiority" are false for many reasons. The laminar flow over the pelet body, various cross sectional dynamics, yaw, lenght to weight ratios and inertia all play a very important part in why soild body pellets do not work as well. One of the most confounding issues that these pellets come up against is the distribution of their weight in relation to their center of gravity and how that weight defines their center of gravity.
: I think in the end to have as good of a performance from a pellet, you need a wasp waisted pellet...until somone comes up with a replacement for lead to make a wasp waisted pellet, there really is no replacement.

twoodle1-at-bigpond.net.au.48750.48746


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 Post subject: I can think of a few.
PostPosted: Fri Jan 30, 2004 4:29 pm 
Economy:
As Scott mentioned, it is expensive to come up with something else.
Efficacy:
Very few things react like lead, and most of the alternatives fail in some aspect or another. Plastic (or Delrin in your example) won’t have the density to keep energy at distance, in the instance of field pellets. They will also shed energy quickly in the instance of match shooting. The weaker power plant will push the pellet against a resistance level that it can’t hope to surmount with it’s lower density. This is why many of the plastic/tin hybrids have conical shaped heads. As if designed as a Diablo style pellet, the waist will more than likely collapse onto itself beyond that of what a lead pellet would do. Also the cross sectional profile would be more affected by wind as it wouldn’t have the mass to use its gyroscopic stability to keep “on target”.
The leading edge of a pellet that engages the rifling would more than likely shred or melt in a high power gun (think of leading but PLASTIC! UCK!) In a lower power gun, the lubricity of the plastic would do well but again small bits of plastic would be left behind or would engage the rifling too much. As a matter of recent history, many of the complaints of the plastic pellets have been as such…too much plastic left behind, too much of a performance loss in guns of medium to low power.
Ballistics:
The Diablo pellet is really very nearly perfect for it’s task. A slightly domed pellet is even better but it isn’t necessary for the match game, and in fact is a bit of a liability when scoring. Again I am sure the plastic pellet in the diablo configuration would be too weak to handle the internal pressures and temperatures on its edges and in its waist area.
Externally it would shed energy too quickly in a match or hunting situation and would be more prone to deviation from flight path due to external factors like crosswind and air friction, this due to its lack of mass/density.
Necessity:
Until it’s absolutely necessary I don’t think there is a reason to do it. I think Sweden and Norway are leading the way in make it necessary for field use in FT matches. I think that until it is absolutely necessary it’s not going to happen, the economy of scale just isn’t there.
Medical/Environmental Issues:
There seems to be enough medical evidence to show that with proper protocol lead is not an issue for the shooter. In terms of the environment I really think that any shooter of a powder burner in putting more lead into the environment than airgunners…but it remains to be seen.

.48752.48750


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PostPosted: Fri Jan 30, 2004 5:51 pm 
Hi Len
THat was very well explained and I think answers the question for me well and truly
Thanks for taking the time
Regards
Tom

: Economy:
: As Scott mentioned, it is expensive to come up with something else.
: Efficacy:
: Very few things react like lead, and most of the alternatives fail in some aspect or another. Plastic (or Delrin in your example) won’t have the density to keep energy at distance, in the instance of field pellets. They will also shed energy quickly in the instance of match shooting. The weaker power plant will push the pellet against a resistance level that it can’t hope to surmount with it’s lower density. This is why many of the plastic/tin hybrids have conical shaped heads. As if designed as a Diablo style pellet, the waist will more than likely collapse onto itself beyond that of what a lead pellet would do. Also the cross sectional profile would be more affected by wind as it wouldn’t have the mass to use its gyroscopic stability to keep “on target”.
: The leading edge of a pellet that engages the rifling would more than likely shred or melt in a high power gun (think of leading but PLASTIC! UCK!) In a lower power gun, the lubricity of the plastic would do well but again small bits of plastic would be left behind or would engage the rifling too much. As a matter of recent history, many of the complaints of the plastic pellets have been as such…too much plastic left behind, too much of a performance loss in guns of medium to low power.
: Ballistics:
: The Diablo pellet is really very nearly perfect for it’s task. A slightly domed pellet is even better but it isn’t necessary for the match game, and in fact is a bit of a liability when scoring. Again I am sure the plastic pellet in the diablo configuration would be too weak to handle the internal pressures and temperatures on its edges and in its waist area.
: Externally it would shed energy too quickly in a match or hunting situation and would be more prone to deviation from flight path due to external factors like crosswind and air friction, this due to its lack of mass/density.
: Necessity:
: Until it’s absolutely necessary I don’t think there is a reason to do it. I think Sweden and Norway are leading the way in make it necessary for field use in FT matches. I think that until it is absolutely necessary it’s not going to happen, the economy of scale just isn’t there.
: Medical/Environmental Issues:
: There seems to be enough medical evidence to show that with proper protocol lead is not an issue for the shooter. In terms of the environment I really think that any shooter of a powder burner in putting more lead into the environment than airgunners…but it remains to be seen.

twoodle1-at-bigpond.net.au.48757.48752


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PostPosted: Mon Feb 02, 2004 6:38 am 
Stability would be an issue if one were to use a different material than lead. Even though it's only 10 meters, the further you get from the density of lead, the worse the consequence. Your twist in the barrel would have to be modified to stabilize any other projectile.
.48855.48744


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PostPosted: Mon Feb 02, 2004 1:29 pm 
Ken you're wasting your time, they have it in thier head that lead is the boogey man. So let them go shoot there tin and steel projectiles until one bounces back and as they say in A Christmas Story "they'll shoot thier eye out".
.48875.48855


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PostPosted: Tue Feb 03, 2004 8:36 am 
Sheesh- take it easy. No one "has it in thier head that lead is the boogey man." Lead's a toxic substance, so some of us are checking out alternatives- not that big a deal. (Well, it obviously is to you, for reasons unrelated.) And as for buoncing, I have an old shirt stuffed inside the pellet box; I doubt bouncing will be a problem.
: Ken you're wasting your time, they have it in thier head that lead is the boogey man. So let them go shoot there tin and steel projectiles until one bounces back and as they say in A Christmas Story "they'll shoot thier eye out".

.48916.48875


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