Monday 27 April 2015

Wildcats by B.Potts - 24/04/2015

Introduction
Wildcats love them hate them , what are they? Do we need them, waste of time? All apply in some way or other dependent on your own views and needs as a hunter.
To the vast majority a standard factory round is more than sufficient and that’s fine, my favourite calibres are .308 Win and .22LR but without development and experimentation these two great rounds would never be in existence. They all emanated from a wildcat at one time or other the difference is most factory loads are just the last development of a series of Wildcat rounds to get to the final design.

As with so many things in life people like to push the boundaries and experiment and improve almost anything to achieve a better product and something truly different. Whether this is for your own personal satisfaction or derived for the need to succeed financially the end result is still the same, a sense of being part of the process and owning something unique.

What`s a Wildcat


Primarily a Wildcatted round is one that has been modified to improve its performance both in terms of accuracy, velocity, and case life. You usually start by reforming an existing cartridge case soyou can then improve the case by removing any body taper, increase the shoulder angle both increasing powder case capacity and hopefully velocity increases. Or just necking up or down so that larger or smaller projectiles can be shot from the parent case, to name but a few modifications. True, this can seem a daunting task to many shooters but in reality most shooters are all ready shooting some sort of wildcat already. Many of the great cartridges available on the market are commercialised wildcat rounds such as the .22-250,.243, not to mention the .270, .25-06, .280 Rem are all standardised wildcats from the parent .30-06 Springfield round. The list is endless.

Getting started

But before you start you have to consider a rather technical list of priorities regarding donor rifle, reloading equipment, availability of brass, dies, cases etc as well as barrel manufacturers and custom chamber reamer makers to chamber your new barrel and dies if necessary.
Although all Wildcats utilise, different cases and consumables there is a uniformed criteria you must follow to achieve your dream rifle.
Do you go the existing wildcat round route such as 6mm AK, .22 Cheetah or say the 500 Whisper or do you go for a unique unknown of your own?
Choosing an existing Wildcat takes a lot of the quess work out of it as reamer prints, load data and reloading technique has been explored before. If you are a Wildcat virgin then this is the route to go first.
The more adventurous canstart bending their own brass to create their very own Wildcat. Some people take an existing case, say a .308 Win and then shorten the case, lengthen the neck and improve the shoulder angle. It may only be a few thousandthsofa inch different than the standard .308 Win but in essence it is a Wildcat and legitimately call it a new name. look at the .204 Ruger this was originally the .20 Terminator!
For the more adventurous a complete calibre change and “real” advantage is what keeps Wildcatters pushing for more. Look at the .260 Rem,originally the 6.5mm Panther it now has .260 Rem AK Imp, 6.5 Creedmoor and similar 6.5x47L, all very similar but with their own individual differences.

Trouble is where do you start. Here`s how I do it.
It all starts with the bullet, yes bullet. I look for a particular bullet I like and want to push at a velocity that interests me. Usually this means a high BallisticCoefficient bullet for better down range performance. Then I see what is out there in terms of ballistics from existing cartridges and see if there is any “room for manoeuvre ” Its getting harder as most cases now have “Wildcatted “ in some form or other.
I would love the luxury to make my own dimension cases but that`s just not economically viable which is why a parent case is used.
Take the .20 Satan Wildcat for example. I love small calibres and when the 50 grain and later 55 grainbullets arrived on the scene I jumped on them.
Here the same weight bullet had a better BC than the standard .224 version so now you need to look at a case that can take advantage of it.
That’s easier said than done. Too big a case and bye bye rifling, to small and there`s no real advantage.
What I do is use Quickload and QuickDesignballistics program to design a new Wildcat from the existing database. In the 20 Satans case I wanted to use the 6x47mm Swiss Match case and then later 6.5x47L case as donor cartridges.
I use the program and actual cartridge cases in front of me to re-design to a form I am happy with.
By changing or completely from scratch building a case in Quick Design you can change at will in the “Virtual world” your new creation.
Alternatively, and I use this method a lot also is to use existing reloading, form dies and change the neck bushing sizes eitherlarger or smaller dependent on final bullet diameter to swage the neck. Then use alternativedies to reform the body or shoulder angle to get a “partial” wildcat . this way you can visualise in real time a prototype.
 With an initial new case design I weigh the case and measure H2O capacity to check internal powder capacity.
I then run these dimensions through the QuickDesign program to see if I am close on my virtual case. Differingmanufacturers cases vary a lot.
Now you need to decide whether you want a tight neck or standard neck dimension. I.e. will you go for a thinner neck and thus necessitate neck turning to gain more precision and neck tension.
With the dimensions sorted I shoot it in the Quickload program with a variety of bullets and powder combinations. This gives a very realistic result for the true ballistics your new creation will take.
It’s here you cross your fingers and the pressure scale stays safe and the velocity figures exceed the factory loading if there is one.
If it works, fine, if not go back re-compute and change a few dimensions, smaller is better, in ballistic a small change can make a big difference.

Now what?

I now print off a case design sheet as a reference as you need to give this to your reamer maker. Here the more info the better as not only does the chamber reamer need to suit your new design but you have to decide on seating depth and thus throat length, neck diameter. If I use a print out I tell the reamer maker the bullet I am shooting and suggest a COAL based on ogive touching lands.
If I have a case made from a parent case I will send three copies but drill out the primer hole and through the case and engraved ”DUD” on it, because my reamer makers are in the USA.
Now wait for the reamer to be made, I use a standard steel reamer but with a live pilot so you can change this to get a true fit into your barrel and with it I order a “Go gauge” to check headspace. Yes only a go gauge and the reamer is a finisher only not rougher.

Now you need to choose a barrel , correct twist rate to stabilise bullet weight, maximisevelocity, rifling lands and profile then barrellength flute or non  flute and of course stainless or moly steel!
Here formulas are available to ascertain best twist rates but when shooting a Wildcat you have to consider barrel erosion extra pressure from too tight a rifling twist. Is three lands better than six? Should the leade in be 1.5 or 3 degrees?, Ratchet, polygonal or flat rifling lands? And of course enoughlength to achieve the extra velocity you hope your new creation will deliver. Trouble is at this point is whether you do really have to just go for it and suck it and see.

Load up

Right you have your barrel newly reamed, chambered and fitted. Now the fun starts.
If the Wildcat is a simple neck down or up you can fire form your load in the chamber to its new dimensions, usually with the bullet in the lands to stop case creep but with amild load. (not always)This means that although the case is formed using mechanical dies it still needs to be shot in the chamber of the rifle to expand it to the correct proportions.

Trouble is you will need some resizing dies and seater die to reload your case. If it’s a known wildcat then there may well be a set of dies out there. I.e. Redding custom shop, CH4D good source.
Sometimes I use existing dies and cut then down or modify to neck, body re-size or even seat. Ie as with the 300 Broad sword and 30-47L, 300 WSM and 308x1.5 respectively.
But for a real one off when neck length case and shoulder all differ then you need a set of dies tailored to your case.
I tend to use blank dies form Wilson or Newlon and then have the gunsmith use the chamber reamer to cut a two dies.
The first will be a neck die where the use of either Wilson or Redding neck bushes can be used to achieve correct neck tension. Plus using the correct seater stem the other die can be used as a seater die If you want a full length die you will need a smallerreamer dimension than the one that cut the chamber or sometimes I use a body die that may fit your new case.

Is it worth it?

On first inspection it may seem a complete faff and also unwarranted expense to go to all this hassle. I cannot agree more but that’s not the point,withoutexperimenting there would be no advantages and in any case some of the Wildcats whether factory adopted or not still desire a look at.
Some only deliver a meagre 5 % velocity gain but the new “look” can be fantastic aka .308 Win AK or you can try a .250 AK that is well worth the performanceincrease. And full blown Wildcats like my .20 and .22 Satan, 6.5 Rapiers and 300 Broadsword keep me happy and out of the wives hair.

Conclusion

That in a nutshell encapsulates the Wildcat ethos, maximum input and effort affords the best final results. If we all drove around in Ford Escorts what a boring life it would be, since time began people have been customising and improving what exists and that’s what interest`s me.
Wildcatting is not for everyone and yes the std calibre’s will suffice for 90 % of all your shooting needs let’s not cloud the water here, but for the shooter who really wants to explore their reloading and creative ideas the Wildcat bug is mighty hard to shake off, tell my wallet!  

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(article by JMS Arms Customer)


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