Plaswad, general notes..

[Guest cookoff013]

so, i`m here again and not got much to do so i`ll start rambling.

first of all, i`d like to say, stick to varified loading data. that is a must.

 

reloading shotshells is assembling components, not working up loads.

 

plastic wads replaced fibre, because they are easily loaded in shells. from a manufacturing point of view, thats great.

plaswads are like cars, why drive an Allegro, when you have a TVR ?

 

and thats the big question thats asked, do plaswads do the same thing?

 

essentially yes and no.

all plaswads are different. different brands have different charicteristics. the main part of the plaswad is to seal the gas produced from the powder, if the gas seal is poor then the pressure will bleed from the seal.

 

how can the seal be poor? well the size and fit of the seal will have an effect. i`ve mesured some and they vary greatly in size.

some have a diameter of .738" and some .722. both of these wads are designed for 1oz target loads. one is my favourite and the other is some generic bland product. i did pick the wads that had 2 different seal sizes.

i am very biased when it comes to these wads.

 

poor sealing wads do produce slower speeds, less pressure and poorer performance.

so a reloader "working up a load" to say 25grains of powder, then swiching to a different wad (a better seal wad), will have problems. (and vice versa)

 

if you relaod plaswads, get the micrometers out and give them a going over.

 

reload safe, shoot even safer.

[Jaguar Warrior]

so, i`m here again and not got much to do so i`ll start rambling.

first of all, i`d like to say, stick to varified loading data. that is a must.

 

I would if i could but i can't - there's always something missing for my needs. Maybe plastic wad, or plastic obturator. wrong shot size.

 

reloading shotshells is assembling components, not working up loads.

 

Spoken like a true clay shooter - my main priority is killing nuisance animals instantly, humanely with no wounding.

plastic wads replaced fibre, because they are easily loaded in shells. from a manufacturing point of view, thats great.

plaswads are like cars, why drive an Allegro, when you have a TVR ?

 

and thats the big question thats asked, do plaswads do the same thing?

 

essentially yes and no.

all plaswads are different. different brands have different charicteristics. the main part of the plaswad is to seal the gas produced from the powder, if the gas seal is poor then the pressure will bleed from the seal.

 

how can the seal be poor? well the size and fit of the seal will have an effect. i`ve mesured some and they vary greatly in size.

some have a diameter of .738" and some .722. both of these wads are designed for 1oz target loads. one is my favourite and the other is some generic bland product. i did pick the wads that had 2 different seal sizes.

i am very biased when it comes to these wads.

 

poor sealing wads do produce slower speeds, less pressure and poorer performance.

so a reloader "working up a load" to say 25grains of powder, then swiching to a different wad (a better seal wad), will have problems. (and vice versa)

 

I hear you, brother

 

if you relaod plaswads, get the micrometers out and give them a going over.

 

I've just one problem with this (takes off camo jacket and puts on lab coat, complete with clipboard and pens in spring clips on front pocket). 500 bar is a TREMENDOUS pressure in real terms. Possibly HUMONGUS, but I don't think thats a real word . I thought my PCP air-rifle was mad at 160 bar. A medical gas cylinder is about 210 bar or more. My workshop compressor bottoms out at 8 bar, and my car tyres are only 2 bar.

 

I'm not sure that a wads behaviour at atmospheric pressure correlates with its behaviour at 500 + bar. Soft metals like lead are getting deformed against each other at these pressures. I've recently been speculating about the performance of harder discs and wads going from how easily they can compress with a probe or fingers, but I know its a long way from what happens in a firearm. The latter is probably more like hitting it with a sledgehammer and then some. :blink:

How well they function in a gun is probably better tested with a standard pressure source at say 600 bar. By this I mean from a cylinder, not the pressure created by a propellant, because this varies with pressure itself. Using a standard pressure, you can now test just the wads performance and see how well it retains the pressure.

I'm less concerned about pressure (the equivalent of speed, both are static values) and more concerned about the rate of change of pressure which is the equivalent of acceleration - both are dynamic values. I've formed the humble opinion that barrels blow when the rate of change of pressure is too high. If you slowly raise the pressure, the barrel might hold.

reload safe, shoot even safer. Be accurate too.

 

JW

Edited March 25, 2011 by Jaguar Warrior

[Jaguar Warrior]

Just bouncing this thread back up.

I thought it was the start of an interesting discussion by Cookoff through which i and others might learn something from our Jedi Masters.

Any takers?

 

JW

[UK fowler]

Just bouncing this thread back up.

I thought it was the start of an interesting discussion by Cookoff through which i and others might learn something from our Jedi Masters.

Any takers?

 

JW

sounds more like revenge of the sith

[Guest cookoff013]

jw,

 

thanks for replying, i thought i needed to give the loaders an insight into wad characteristics. this is often misunderstood. there are good wads and bad.

i will say again, stick to verified pressure data. changing components will alter the speed,and pressure, which way will they go?

 

i would use any shotsize upto and including #1 in any lead recipe. anything after that is more classed as buckshot and has bigger payloads and faster velocity. the powders used for the buckshot series is very slow in comparison.

 

reloading shells is assembling components. working up loads is very dangerous. try and keep below the maximum psi and alittle bit, i have a liking for loads that run at 9000psi. enough for good burn and should give great performance.

 

recipe selection is still the reloaders variable. no point in trying to shoot boar with 1/2oz of #10.5 at 100fps. thats a lemon cartridge.

just pick the right cartridge. it isnt hard. what exactly do you want to shoot? lemons or the greatest ammo ever made?

 

the only true way to see how efficient a wad is, is to shoot all them with the same generic recipe. say 1oz, and 20 grains of AS.(i`m talking 1oz target wads here)

the wad that gives the highest pressure is the wad that seals the best, the wad that pushes the shot the fastest is the fastest wad. its knowing which wad is the best for the application in which it is applied.

[Jaguar Warrior]

Quote Cookoff013 the wad that gives the highest pressure is the wad that seals the best, the wad that pushes the shot the fastest is the fastest wad.

 

This implies that the friction of the wad plays a part, and not just the effectiveness of the seal.

This then forced me to think about situations where the seal and the speed were different - my instinct was that the better the seal, the better the speed (because less pressure is wasted with a good seal).

 

I guess you could theoretically have a wad that sealed so well, it gave massive pressure but couldn't move.

But could you have a wad with a really poor seal, that was the fastest?

I guess so - when all the other wads of the same weight caused more friction but gave a slightly better seal.

 

Am I on the right track?

 

JW

Edited March 30, 2011 by Jaguar Warrior

[Guest cookoff013]

the thing about how a wad responds, is the recipe. there are several recipe types.

here are some clues

 

huge powder charge, light shot charge, either the wad is inneficient, or the powder is too slow for this application.

small powder charge, either the seal is very efficient, or the powder is too fast for the application.

 

you can have all those scenarios that you suggested. but the massive pressure scenario will move something.

 

you are quite correct that different wads have different friction, but what you call friction i call a seal.

 

in a perfect world, you`d take that 1oz recipe, 20 grains AS, over cx2000, try 10 different wads, get the speed data, and pressure data.

only then can you say wad x is better than wad y. because of the pressure and speed. loaders either like to hit a speed or a pressure.

 

if you then loaded 22grains then, a different wad might be better. (no, seriously.)

 

i`ve got a wad for a steel load, it is the most inneficient wad ever, it takes a huge powder charge to get the load moving. it has nicks in the base to bleed pressure off. the recipes are formulated to ovecome the pressure loss. substituting the wad for an efficient one will get the load above 14kpsi. the load isnot a lemon because it hits over 1600fps at only 9000psi (1600fps being "very fast")

 

vectan A0 and tecna-n both powder are suitable for launching 36g loads. vectan A0 gets almost 1300fps, at high pressure, but tecna-n can get 1600fps at low pressure, which ones the best? neither, they both do the job. will the different wads make a difference. yeas they would.

 

in the literature, about reloading. it is advised that not to change components. but says on old guns reduce charge 10%, loads that are 3/4oz need 10000psi to burn well, 1oz and general loads need 9000psi.

 

if you start reducing loads by 10% i could envisage changing the wad, will not produce excessive pressure.