AusVarmint

i've gone and done it again, thought too much about something and now it sounds like a good idea.

anyway, i can't really find much on the jab 20 but i know a few of you have one, trevort?? little help

anyway, the vartarg as i understand is based on the 221 fireball so that's the direction i may head for but..... what's this jab 20?

what will i need to do to get brass up and running? should i get 221 brass and neck down? i have 17 fireball brass but not sure i want fiddle with that. and dies, can i cut down 204 dies to use for the job?

basically thinking a big cut and shut on a 204 chamber and dies to fireball length.

shooting is my heroin addiction

jab 20 is a short 204R using 223 brass.

20VT is neck down 221FB.

20VT will push 32grain to over 3800fps.

Remington 221FB brass is average, but does the job.

I made my 20VT brass from 223Lapua using Redding forming dies, which I still have. This brass was unreal!!!

The 20VT is very efficient, accurate, no recoil, and a dream to shoot!

Cheers

I believe the Jab20 Just another bloody 20 is Trevort's brain child

Another option is the Vartarg Turbo which is the 222 necked down to 20cal

I think you could pick just about any and you'll be happy, that T3 barrel you got was going to be a vartarg turbo rimmed in my martini or a 20 bobcat, look that one up its based on the 222 as well, bit like what the 204 ruger to the 222 mag, it has straighter case and different shoulder, I have a reamer print if you want to look at it but do a search on 20 bobcat.

Ryan

Whatever you do, just make it easy with case forming and dies.. Having something with a cool name that does exactly the same as something else that is readily available in components is easier.

Or something wildcat where current unmodifed dies can be used.

How about a 223AI necked to 20cal. Dont have to push back shoulders, can use 223AI dies with smaller bushing. Would be a cracker!!

CHeers

At the risk of being boring, have you considered the 20 Practical? A simple neck down from 223 brass - very easy and from all accounts a good performer.

MISSED will be along sometime soon to sing the praises of the 20VT, which is a nice looking case that gets impressive velocities for its size.

stinkitup wrote:I believe the Jab20 Just another bloody 20 is Trevort's brain child

Another option is the Vartarg Turbo which is the 222 necked down to 20cal

I think you could pick just about any and you'll be happy, that T3 barrel you got was going to be a vartarg turbo rimmed in my martini or a 20 bobcat, look that one up its based on the 222 as well, bit like what the 204 ruger to the 222 mag, it has straighter case and different shoulder, I have a reamer print if you want to look at it but do a search on 20 bobcat.

Ryan

ah so you bailed on it. thanks..... you caused me to spend more $$

yeah got loads of 222 brass but i want a lower velocity, lower report 26gr-32gr bullet flinger. the 20 vt sounds like it fits the bill.

Thanks for the intro Jason,Andrew I cannot comment on the Just Another Bloody 20 Cal (it has been to my place twice but remained unused).As AI has said the 20 Vartarg is based on the 221 Fireball case and to form you just have to run the parent case through the Vartarg full length die that is it no trimming or turning.Or you can do as I did and neck up from 17 Fireball.From what I have read 2207 works very well or if you can get someRE7Here is a pic with the 20 VT with the 222 and 204 for comparison
My 20 VT is still a couple of weeks away I will post some pics of the devastation

thanks missed. nice line up

i have heaps of 222 brass.... soo this could be a 204-222 job. hmmm 204 ream the chamber to 222 shoulder length and chop the necks back. doing that could save me spending anymore $$$

thanks stinkitup, ryan, you gave me more to think about

JAB was named by Andrew (AKA Missed) when I posted was my attempt to make a Tac 20 different enough to give it a name. He said ïts just another bloody 20 cal"
Hence JAB 20. Its an Ausvarmint joke but I took it seriously, its stamped on the barrel and on the rego papers!~!!!

A 20 Pactical is simply the 223 case necked down, a 20 Tac has the shoulder altered to the same angle as a 204 and a longer neck.

Believe what you like about the many theories posted about longer necks but I wanted one. Shane didnt have a Tac 20 reamer so my idea was cut a 204 fl die short and force the 223 brass in to push back the shoulder and neck down in one go. Some teething problems have been overcome and it works. Does it work better than a 20 Prac, hmmm unlikely but I wanted it this way. If you want one, I've got the bugs sorted, you will have the second in OZ!!!

Now why not a VT for me, simple, it seems to be favored with 32 pill, the 39 and 40 are the long range choices and the VT doesnt have the boiler room to get them zinging. Now will I notice, well again, Missed can tell you I get the 100m to 300m bunnies but any further than that are generally safe so a VT would probably not handicap me!

Trevor I did see your last shot on that bloody windy September afternoon.My borrowed Rangefinder read 347m And your other shot at 320 m to remove his sandshoe across wind was all good.
Andrew go to Saubier.com there are a lot 20VT and 20VTT lovers there.I went for a 20 VT for similar reasons you have given Low noise long barrel life and Accuracy to burn.Also as I have said in another post I got a 26" 1/10 twist barrel.The idea of this was when and if I have an urge(this happens less with age)I can rechamber to 20 VTT ,Jab 20,20 prac tac or 204 and launch 50 grainers.

ah now i get it just another bloody 20cal

so if i do the same to a 222 case with the 204 fl reamer what will i end up with??

JAB 20 MKII??? how about a 202?? 20 deuce? or is that the 20 vt turbo?

someone stop me please.

so trevort. what were the problems of jamming the shoulder back and necking in one go when you were sizing the JAB 20? did you use a chopped 204 die aswell?

seriously thinking of going with the 222 case and force the neck shoulder to 30 degrees and stop at the outside of the shoulder. 222 is closer to the 221 firball and it might help ejection with the action i'm going to use. my tikka lsa 55 that's currently 17rem, i think a fireball length case won't clear the action since i've had a fiddle. feeds fine though.

Andrew I have a Jab 20 die here somewhere
What you are thinking of doing is probably closer to a 20 Extreme I think.
The 20 VT can punch a 32 grainers at 3800 while burning 19-20 grains of powder and the 39`s at 3600.If you do some studying you will find this is not that far behind the bigger cases.Trajectory differences are very minor. Vartarg dies are available from Redding,RCBS ,Wilson and Hornady.
Another part of my plan is to prise(spelling) a set of forming dies from another members hands and form up from 222/223 Lapua brass.

MISSED wrote:Andrew I have a Jab 20 die here somewhere
What you are thinking of doing is probably closer to a 20 Extreme I think.
The 20 VT can punch a 32 grainers at 3800 while burning 19-20 grains of powder and the 39`s at 3600.If you do some studying you will find this is not that far behind the bigger cases.Trajectory differences are very minor. Vartarg dies are available from Redding,RCBS ,Wilson and Hornady.
Another part of my plan is to prise(spelling) a set of forming dies from another members hands and form up from 222/223 Lapua brass.

thanks missed, i'll see what my gunsmith can do with the 204 dies first. hoping he can cut some off them, being very tight on this build..... as usual i guess

anyway, if the 204-222, exetreme/dog donga...... hmm there's a name, 20 dogdonga doesn't pan out a 20 vt could go ahead.

my plan is to shoot barnes 26gr or 32gr bullets at foxes and hope they don't get spread across the country side. skins for a rug.

so bit longer than the 20vt may help with extraction since i'm worried about that but don't really want 223's worth of case capacity.

plus i have an absolute bucket load of 222 cases sitting around.

andrewk wrote:ah now i get it just another bloody 20cal

so if i do the same to a 222 case with the 204 fl reamer what will i end up with??

JAB 20 MKII??? how about a 202?? 20 deuce? or is that the 20 vt turbo?

someone stop me please.

so trevort. what were the problems of jamming the shoulder back and necking in one go when you were sizing the JAB 20? did you use a chopped 204 die aswell?

seriously thinking of going with the 222 case and force the neck shoulder to 30 degrees and stop at the outside of the shoulder. 222 is closer to the 221 firball and it might help ejection with the action i'm going to use. my tikka lsa 55 that's currently 17rem, i think a fireball length case won't clear the action since i've had a fiddle. feeds fine though.

I believe that would be called a 20-222 improved probably.

Check out this page re the 20 bobcat http://customriflesandcartridges.com/20Bobcat.htm
He states a 33grain vmax forming loads at 3750 and formed brass at 4100 thats singing nicely. 40deg shoulder and a long neck seems to work nicely and 222 brass is easy to find.

Ryan

no problem forming brass, easy, one pass and done (well maybe 2 passes if the 223 had been fired before, they need to be FL in a 223 die first before going in the shortened 204 die.

problem was that the chamber is formed with a 204 reamer run short. But that means the base of the reamer doesnt get into the chamber, so the taper of the case (fatter at the base) isnt accomodated for. Rounds would chamber but on firing a case expands and then shrinks back. No room for this to happen so the case would just stick in the chamber.

Once I knew what the prob was (tried a few variables) i took it back to Shane. He ran in the 20 prac reamer, not far enough to alter the neck and shoulder but since its shorter the base of the reamer gets into the chamber to widen it 2 thou and give me the clearance I need for extraction.

Go over to Saubier and talk about your idea. Small calibre fanatics!

What about getting a chamber made like a 222 AI, only necking down, say 4 5ths or 3/4 of the 222 neck so you leave a false shoulder to fire form off. hmmmm.

I like 20 cals!