Sunday GunDay: 20 Practical AR — Very Accurate with Low Recoil

If you want to use an AR-platform rifle in the varmint fields, consider getting a 20-caliber barrel chambered for the efficient, low-recoil 20 Practical cartridge. The 20 Practical is simply a .223 Remington necked down to 20 caliber. The parent .223 Rem cartridge of course works great in an AR, but the 20 Practical offers some notable advantages for high-volume varmint shooters. The 20 Practical delivers very high velocity with very low recoil while still providing outstanding accuracy. The 20 Practical is great option for folks who favor “fast and light” — smaller, lower-mass bullets traveling at very high velocities. This little cartridge can launch 40-grainers at over 3900 fps, and 32-grainers even faster. This makes the 20 Practical a great choice for an AR-based varmint rifle.

20 Practical Ultimate Varminter
Over a decade ago, as a “proof-of-concept”, AccurateShooter.com created a 20 Practical AR15 Ultimate Varminter with a custom 20-caliber upper from Robert Whitley of AR-X Enterprises, LLC. That project rifle was ultra-accurate — every 5-shot group out of the gun was less than the size of a dime. That gun was auctioned off, but Robert Whitley produced many other 20 Practical AR15 uppers. (The 20 Practical cartridge is simply the .223 Rem necked down to 20 caliber — you can use standard .223 brass and load with standard.223 Rem dies. Just swap in a smaller expander and use smaller neck bushings.)

Robert learned that the accuracy of the first 20 Practical AR15 was no fluke. After building six (6) more 20 Practical uppers, he tested them for accuracy and they all shot great. These uppers featured DPMS low-pro receivers with side-charging handles. They are fitted with PacNor 1:11″ twist, 3-groove stainless barrels. Three of the uppers had 24″ barrels, two had 20″ barrels, and one had an 18″ barrel (See below).

Robert reports: “We [made] more 20 Practical AR15 uppers and I have to say I am astounded by the accuracy of [all those uppers]. For shooting little tiny groups out of an AR15 with bullets going 3500+ fps, it’s hard to beat the 20 Practical cartridge.”

In four of these uppers I shot re-sized Winchester brass using 25.3 grains of WC844 powder with Berger 40gr BTHP bullets loaded at 2.225″ OAL (about .015″ off the lands). WC844 is inexpensive military surplus powder that is nearly identical to H335. I tried three different primers and the choice did not seem to matter (CCI BR4, Rem 7 1/2s and Win Small Rifle — the old silver ones). All these four uppers shot great.”

Below is an animated GIF with targets from uppers #6, 10, and 11. All groups are mag-fed, 5-shot groups shot at 100 yards using a front rest and rear bag.

20 Practical Shooters Explain Why They Love this Little Cartridge

A popular thread in our Shooters’ Forum focuses on favorite variants of the .223 Rem cartridge. The thread asks: “What is your favorite and most versatile round that you have made from a .223 Rem parent case?” Many cartridges were named, but the wildcat cartridge cited most often was the 20 Practical. Here are some comments by Forum members, who explain the appeal of this great little 20-caliber cartridge:

“The 20 Practical is just a hoot to shoot. Outstanding precision, minimal recoil, easy case forming and inexpensive to shoot. What’s not to like?” — JLT

“The 20 Practical for me. Never had as much fun shooting a rifle as I did with the 20 Practical. Also, [it is] the easiest wildcat to form. Just get cases, a couple of bushings to get the right neck tension, and you are shooting.” — NMKid

“My favorite was and is the 20 Practical. No fire-forming, no neck-turning, and with the increased BC of the 20 Cal bullets, it’s hard to wipe the smile off your face in a prairie dog town[.]” — Region Rat

“20 Practical and the [original] .223 Rem are my favorites. Accurate, cheap to shoot. The 20 Prac allows you to see your hits and it’s fast.” — Alguapo

Smart Tips on Forming 20 Practical Cases

Varmint ace Warren B, aka “Fireball” in our Forum, explains how to form 20 Practical Cases. “Forming 20 Practical cases is very easy and no fire-forming is required. Start with any good quality .223 Rem brass. One can simply run the case into your bushing die with the appropriate bushing and call it done. I however like to make it a little more involved by doing the neck reduction in steps. I find that taking steps doesn’t overwork the brass as much as one step does. Also, if you resize the neck in too large of a step, sometimes, depending on the neck thickness, the neck will not be dimensionally what you would expect when finished. This is especially important towards the last step when one is getting close to the final required neck diameter.

For my cases the first thing I did was to run them into an old RCBS .223 Rem full length die with the decapping assembly removed. This will take care of any dented necks on the raw cases and bring the necks down to around 0.243″. Since all standard full-length dies oversize the necks way too much, starting with a .223 FL die actually reduces the neck diameter quite a bit — and obviates the need to buy an extra bushing for the first step. I then use my Redding Type-S die with two bushing sizes to get down to where I need to be. In other words, I start with the FL sizer, then move to a Type-S with a 0.233″ bushing and finish with a 0.228″ bushing. I use progressively smaller increments in size between the reductions.”

Efficient Loading of 20 Practical Cartridge

The beauty of the 20 Practical as a cartridge is its simplicity. You can start with .223 Rem brass, and use .223 Rem dies with minor modifications. No special case-forming dies are necessary. To prepare the brass, all you need is a .223 Rem bushing die with .233″ and .225″ bushings, plus a 20 Cal decapping rod assembly, Redding part #14206. First remove the .223 Rem decapping assembly and replace it with the 20 Cal decapping rod assembly (the same assembly used with Redding .204 Ruger dies). Put the .233″ bushing in a Redding Type ‘S’ bushing die and run your cases through for a first pass. Then swap in the smaller .225″ bushing for the second pass. Now your brass is sized and ready for loading.

You can seat bullets using a regular Redding, Whidden, Lee, or Hornady .223 Rem seating die with no mods. Use the .225″ bushing for neck sizing for all subsequent loadings once the cases have been necked down the first time. It is simple and easy.

In the above video, Robert Whitley shows how to neck down .223 Rem brass using two bushings in sequence. Then seats a bullet with the Redding Comp Seater die. To save time in the video, Robert skipped the steps of adding primer and powder. But those steps require no special equipment for the 20 Practical.

20 Practical vs. 20 Tactical

Varminter Kevin Weaver, who shoots both the 20 Practical and 20 Tactical, states that: “Both the 20 Tactical and the 20 Practical are fine .20 caliber cartridges. However, my favorite would be the 20 Practical. The 20 Practical gives the SAME performance as the 20 Tactical without fire-forming, or having to buy expensive forming dies.

So with the 20 Practical you do less work, you shell out a lot less money, yet you give up nothing in performance. What’s not to like? To create 20 Practical cases, just buy a .223 Rem Redding Type “S” Bushing Die set with a .230 or .228 bushing and have fun with this great little cartridge.

The 20 Practical and the 20 Tactical are almost identical cartridges. There are only slight differences in case outside diameter, shoulder angle, and case body length. Neck length on the 20 Tactical is a bit longer, but there is still plenty of neck on the 20 Practical to grip the popular bullets, such as the 32gr V-Max.”

20 Practical and 20 Tactical Specifications:

Parting Shot — Yes the 20 Practical works in Bolt Guns too!

“Favorite .223 Rem Wildcat? The 20 Practical hands down for me. I have two of them built on Savage actions right now. One has a 20″ BHW barrel and the other has a 26″ Criterion. It is my go-to caliber for shooting up a Prairie Dog town and the ones I have are insanely accurate. Here are some typical 100- and 200-yard groups with my 20 Practicals.” — IA_Shooter