So, this seems like a pretty good deal. Can order in with no FFL and get a lower locally.
http://palmettostatearmory.com/psa-16-carbine-length-5-56-nato-1-7-phosphate-freedom-rifle-kit.html
Is the standard 1:7 twist barrel going to stabilize a 55-55 gr. bullet and be accurate enough out to 300 for yotes or should I look for a 1:8 or 1:9 barrel instead?

Go 1-7 for the heavier, longer bullets. Slower for shorter bullets.

Here's a barrel makers suggestions.

http://riflebarrels.com/calibers-and-twist-rates/
Towards the bottom is a chart.

Yeah, I get that. According to that chart, I would have to have a barrel custom made to shoot a 50-55 gr bullet. I have seen no production AR barrels with a 1:12 or 1:14 twist.

What is the intended use for this rifle?

Get as close as ya can i guess.

This outfit does, and i believe Kreiger does too, but then we're starting to talk money. I can't help other than custom barrels, just thouht i'd give ya the info so you have an idea of what would be best if obtainable.

http://www.shilen.com/ar15Barrels.html

Making coyotes fall over and target shooting.

You reloading all the ammo?

I could spray a lot of lead to find my target and still be money ahead..LOL

Marty, I would probably reload any hunting ammo. I might shoot some factory ammo for plinking purposes and to generate some brass..

White oak arms have 1/12 very high quality.
Used by a lot of competitive shooters
I use one of their uppers in twelve twist
Very accurate and has the Wilde chamber.

Wow, there are a crapload of web-sites selling AR parts! I've probably looked at 20 or so and have not seen the site you pointed out hippie. Thanks. Maybe I buy the kit, then a barrel and then start over with the left-over barrel...

Your welcome Keck.
I don't like to accept mediocracy when it comes to guns for a few extra dollars.

Well, I've never owned a "black rifle" before so I hate to drop a bunch of cash and hate it. On the other hand, if I love it, I can gift my first to the little lady and build the perfect rifle for myself. There are worse ways to blow money..

LOL, i hear ya!

It all depends on what you expect from it. I get (This word is unacceptable on Trapperman) at guns too easy if they don't group.

My 1in 8 shoots 55 Great under an inch all day with good factory ammo. Only hand loaded 62 grain so far for an antelope hunt 1/2 moa. This from a stag heavy barrel. My son gets 1" from factory ammo with a cheap barrel 1 in 8. If you go 1-8 you can shoot heavy bullets also. If the wind lets up tommorow I'll let you know how 40 grain vmaxs shoot got 3 different powders loaded to test.

Some folks might find this somewhat informative..

Look for a 1-8 or 1-9. Find an upper without the front sight, no A2 flash hider and different hand guards. The one in your link is not the greatest choice for varmints, imo of course Lot's of these on the link below are out of stock, but will give you some different options to look at for the same money.

A2 flash hider is brutal for noise, get just a no threaded end, or take the flash hider off and get a thread protector.


https://www.bearcreekarsenal.com/upper-assemblies?spec_twist=10

As a few of the others have said. I have had great luck with a 1 in 8 with 55 grain bullets. I have shot up to 77 grain bullets, but it does fall off some with the 77's. 62 grain shoot well too.

Look up what a nitrate barrel is before you buy, I'd spend a little more on a SS barrel kit and have less to worry about that way.

Found this at a AR site take it for what it's worth!

It outlasts hard chrome. The neat thing (well, there are several) is that the process is a surface conversion "coating" meaning that there is no geometry changes. And, no, it's not a coating, technically. It's ferritic nitrocarburiation by name. LWRC uses the process, as stated as well as Glock, HK and at least one Euro bolt gun manufacturer. I suspect that MANY Euro gun manufacturers utilize ferritic nitrocarburiation processes. If you're interested contact Rock Creek Barrels.

Mechanical Properties are better than hard chrome for both salt bath and wear resistance, too.