20 cal cartridge question

[Hotshot]

Just suppose if you short chamber a 204R reamer then shorten 204R dies to match so that you run a 223 case into this die and form a 20 cal cartridge with a 30 degree shoulder. Would this be a 20Tac or would it be a 204R/223?
I just purchased someone's unfinished project and got the barrel, dies, brass.
I don't know if I want to fiddle with it or just make it a 20Practical which I already have and love.

[ae35gunner]

Sounds to me like it would be a 20 Tactical...unless the goal was to try and claim a brand new chambering to get around any proprietary issues with Todd Kindler, and to rename it in honor of plagiarism. What would it be called anyway...a 20 Polythumpinator?? No disrespect intended, but I guess I just don't get the point, and life is too short to sweat it anyway. JMHO. Regards and a Merry Christmas ALL my Saubier Brothers, Charlie

[TAJ45]

How short is short? What are the dimensions of the short chambering? Shorter, longer than a TAC, shorter than a Prac? No written or unwritten guidelines I'm aware of.

If you don't really know what you have, do a chamber cast.

[ae35gunner]

On second thought after reading TAJ45's post, if you really ARE unsure of exactly what you've got (I didn't understand your post to read that way), then TAJ45 is right on the money with his recommendation to cast the chamber. BUT consider this...if you already have a 20 Practical and really like it, why not take a walk on the (mild) wild side and consider making this one a 20 VarTarg? Just something to think about...AND you just might end up being another one of us who have been bitten by the 20 VT bug and are now infected beyond recovery Good luck with your project whatever you decide, and keep us posted so we'll know how you are progressing!! Regards, Charlie

[sgtg]

Hotshot; You sure can, I've short reamed several cartridges.
First get the dies and make a case, sometimes the chamber can be a little small (for the body of the case) when short reamed.
(240-320 emery cloth on a wooden dowel will fix that) hence the reason for a made up case.
Use a 20 Tactical headspace gage.
No problem for about any machinist. sgtg out

PS: Should have read all your post, sorry let me start over.

(Your question) Just suppose if you short chamber a 204R reamer then shorten 204R dies to match so that you run a 223 case into this die and form a 20 cal cartridge with a 30 degree shoulder. Would this be a 20Tac or would it be a 204R/223?

I have a few questions to answer you correctly.
What dies and brass did you get? Is it already chambered to 204? Sorry for the confusion. sgtg out

[Hotshot]

I already have this in hand. The guy I bought it from called it 204/223. The guy he bought it from built it and he called it a 204 short. I don't have a 20Tac but this sure looks like one to me unless the neck length is different.

[sicero]

Several years ago I short chambered the 204 to use 223 brass and by reaming the neck of the chamber with a .232 chucking reamer 0.100" deeper.

This effectively shortened the freebore by that amount and made the neck
of the case about the same length as a .222 neck.

To do this, start with the 204 die and cut the base of the die off until you have
a case the length you want. Using all of the 223 case.

Now you can cut the end of the barrel off the same amount until the case fits.

You will have to ream the neck a little since the 223 brass is thicker.

I have never had a problem opening up the neck of the die with a twist drill.

You can't piddle around or the end of the drill will burn on the die.
Just shove it thru. There are several of these around.
I have loaned my neck reamer to several of the guys here.

I shoot mine around 3750 with a full length barrel.

I also have this chambering in a CZ527 with a 19' barrel which cuts the fps
down to about mid 3500.

Kenny

[sicero]

Originally Posted by sgtg

Hotshot; You sure can, I've short reamed several cartridges.
First get the dies and make a case, sometimes the chamber can be a little small (for the body of the case) when short reamed.
(240-320 emery cloth on a wooden dowel will fix that) hence the reason for a made up case.
Use a 20 Tactical headspace gage.
No problem for about any machinist. sgtg out

PS: Should have read all your post, sorry let me start over.

(Your question) Just suppose if you short chamber a 204R reamer then shorten 204R dies to match so that you run a 223 case into this die and form a 20 cal cartridge with a 30 degree shoulder. Would this be a 20Tac or would it be a 204R/223?
I have a few questions to answer you correctly.
What dies and brass did you get? Is it already chambered to 204? Sorry for the confusion. sgtg out

Great post. exactly the same as I do. Make the case first. Kenny

[Hotshot]

Well I have a 3 die set of Lee dies that are obviously shortened but I don't know exactly how much. The savage barrel compared to others seems to be a little more than 1/8 inch shorter. So it appears that I have what sgtg and sicero have decribed. I have some samples of brass that are 223 length but have the 204 profile at neck and shoulder.
I still don't know what to call it. Is this a 20Tac or something else?

[Bill K]

Originally Posted by Hotshot

Well I have a 3 die set of Lee dies that are obviously shortened but I don't know exactly how much. The savage barrel compared to others seems to be a little more than 1/8 inch shorter. So it appears that I have what sgtg and sicero have decribed. I have some samples of brass that are 223 length but have the 204 profile at neck and shoulder.
I still don't know what to call it. Is this a 20Tac or something else?

If it is the same length and profile, but just necked down to 20 cal. is that not just a 20 Practical ?
Why not open it up to 20 Practical AI (20-223/40 degree shoulder) and have the improved version to go with you standard 20 Practical.
I had one opened to the AI version and now shoot that one 90 % of the time, along with having a 20 SCC in another rifle. Both are outstanding cartridges, for varmints and all. Bill K