Best AR feeding .20 cartridge?

[TZaun]

I'm going to build a new AR platform using some form of .20 caliber cartridge. What are my best options for a great feeding cartridge? I'm going to use it primarily for coyotes and will more than likely put a suppressor on it. I have a 25 WSSM currently and it is not fur friendly, to say the least. I've never had a .20 and would really like to try one on coyotes. Bullet recs and twist rates for said recs are greatly appreciated.

 

[pdhntr]

I'm going to build a new AR platform using some form of .20 caliber cartridge. What are my best options for a great feeding cartridge? I'm going to use it primarily for coyotes and will more than likely put a suppressor on it. I have a 25 WSSM currently and it is not fur friendly, to say the least. I've never had a .20 and would really like to try one on coyotes. Bullet recs and twist rates for said recs are greatly appreciated.

Simple.

Practical 20, 1-11 twist, shooting the Berger 35 gr.

Jim

 

[Phil]

.20 Practical.......

 

[hogpatrol]

.20 practical. 1-10 twist for up to 40gr bullets. Use good brass and it will feed better than some of the junk .223 ammo being sold.

 

[squirrelsplitter]

Any of the 20 cal will feed great. Just keep the COAL less than 2.260 and match the receiver to the M4 feed ramps on the barrel extension. Use a chainsaw file and just cut the aluminum to the same width and angle as the barrel extension. Not a single fail to feed since I started doing this.

 

[TZaun]

3 suggestions for a 20 Practical already. I will do some searching later tonight to find out more info on it, but what is it, exactly?

 

[hogpatrol]

3 suggestions for a 20 Practical already. I will do some searching later tonight to find out more info on it, but what is it, exactly?

.223 / 5.56 necked down.

http://www.accurateshooter.com/cartridge-guides/20caliber/

 

[Fast14riot]

Another vote for .20P. Love my 24" 1:10 BHW AR. Handles 32s and 40s just fine.

Do remember, you will need new cleaning rod, powder funnel, jags, etc as most common stuff starts at .22

 

[5spd]

20p from here also.
I built 3 Ar15s with BHW bbls 1/10" tw, 22"long, rifle length gas, adjustable gas block.
Feeds/function very smoothly every time.
Owners are very happy with them.
They are all running the 32g Vmax/Zmax, 32g varmageddon or sierra bullets.
Forming 20P brass from .223 brass is easy.

 

[jepp2]

20 Practical. Feeds just as well as the 223. IF you decide to go 204 Ruger, some lower/upper have feeding issues and due to the longer case, magazines can be an issue. The only way to use PMAG's is to file down the guides to allow for the longer case length.

 

[vlcakc]

I use standard, unmodified 10-round PMAGS in my Lilja barreled, CMT billet upper .204 Ruger AR with no problems whatever. Had no idea it wasn't supposed to work, so just went ahead and shot it! Have been shooting mostly factory 40-gr VMax Hornady and Fiocchi ammo. It's just as reliable as the .223 upper. Vic

 

[Tommie]

20 Practical. 100%

 

[Terry O]

And another vote for the 20P with either a 10 or 11 twist.

 

[rcw3]

We have built a whole lot of 20 Practicals for customers - - you cannot go wrong with that cartridge out of an AR-15 (like "bread and butter"). The 204 Ruger is not ideal out of an AR-15 because the longer case length (1.850" max case length vs 1.760" for 20 Practical) makes it so that even if you have a zero freebore reamer (which SAAMI 204 Ruger reamers do not, they have a .100" freebore), the 204 Ruger chamber is so long that when you load bullets at magazine length (2.250") the projectiles have to jump a mile to hit the lands (i.e. not ideal for "tack driving accuracy").

Robert
www.6mmAR.com

 

[pdhntr]

We have built a whole lot of 20 Practicals for customers - - you cannot go wrong with that cartridge out of an AR-15 (like "bread and butter"). The 204 Ruger is not ideal out of an AR-15 because the longer case length (1.850" max case length vs 1.760" for 20 Practical) makes it so that even if you have a zero freebore reamer (which SAAMI 204 Ruger reamers do not, they have a .100" freebore), the 204 Ruger chamber is so long that when you load bullets at magazine length (2.250") the projectiles have to jump a mile to hit the lands (i.e. not ideal for "tack driving accuracy").

Robert
www.6mmAR.com

So now that Robert has brought up COL and freebore (re. 204) keep in mind that (depending on the reamer used) you will have to check the COL on any bullets you wish to use (re. the Practical). This may seem like a PITA, but the accuracy advantage far out ways this. My reamer is from PTG and I don't know off hand what the freebore is. If I can locate the print I will post the freebore. I don't want to contact PTG to try to get the print. But this is a sample of the COL that I have with mine.

39 Gr. Sierra BK 2.250
35 Gr. Berger 2.203
40 Gr. Berger PN 20304 2.243
40 Gr. Berger PN 20404T 2.230
40 Gr. Nosler BT 2.221
40 Gr. Hornady V-Max 2.195

Point being, I like to be able to reach the lands, and then back off to find the best accuracy, within the limits of most mags.

Not that you couldn't do this with other chamberings, it's just seems easy to me in the Practical.

Jim

 

[Fast14riot]

My BHW has a 0 freebore, I believe it is a PT&G chamber.

 

[hogpatrol]

With the correct .20 Practical reamer, you can load in to lands with any .20 caliber bullet and still be inside the magazine length on an AR. IIRC, with the 32s jumping .010, I had about a sixteenth of an inch clearance in the magazine.

 

[Fast14riot]

With the correct .20 Practical reamer, you can load in to lands with any .20 caliber bullet and still be inside the magazine length on an AR. IIRC, with the 32s jumping .010, I had about a sixteenth of an inch clearance in the magazine.

My chamber (0 freebore) with 32vmax I'm at 2.262 coal to the lands, I load 2.250 on those. I can fit 2.270 in my p-mags. I'll have to double check my notes for BTO measurement, but that isn't important for mag length.

 

[1raggedhole]

20 Practical is a great choice for all the mentioned reasons. But, I shoot about 1500 rounds of 204 Ruger per year out of a White Oak upper and it is amazing. 26" bbl 10 twist, shoots 32 gr bullets into tiny little groups. Yes, they jump a long ways with 2.25" OAL, but it doesn't seem to matter. My only advice against the 204 Ruger is brass cost and availability. BTW, White Oak make the same tack driver uppers in 20 Practical, they are just not listed on the site, you have to call them.

 

[jfseaman]

20 Practical.