I am getting ready to build a 308 AR. I can get a Faxon 5R barrel for $30 more than I can get a standard barrel. What are the advantages of the 5R rifling? I am assuming the extra $30 is worth it? It will be for a gift for my little brother, he will probably use it for hog hunting. Looking at a 18" barrel. Please give me your thoughts.

5R rifling is supposed to enhance accuracy. Many sniper rifles use 5R.

Key adjective in bold above...

5R may help if your trying squeeze another 0.0001 out of a bench rest rifle. The rifling is a classic example of an appeal to novelty. It must be great because it's different and you know, it had some benefits for a bolt gun barrel so it must be good for every barrel ever made. Clue: Krieger, one of the most respected names in precision barrels, will not make AR-10 pattern barrels with 5R rifling. The fact Fauxon makes one doesn't surprise me.

So are you telling me my Bartlein 5R is not cut rifled?

From Bartlein:

Which is better 5R style rifling or conventional rifling?
In terms of accuracy and barrel life we don’t see a difference. There are a lot of varying opinions on this. Some say if you want hard core accuracy to go with conventional rifling. We feel in the real world there is no real difference. The more uniform your bore and groove sizes over the entire length of the barrel, the more uniform the twist and the straighter the blank the more forgiving the barrel is going to be.

5R was introduced to this country by Boots Obermeyer but was developed in Russia, I believe. Boots is probably the best barrel maker alive today, and he made the original barrels for Knights SR-25s. His protege, Mike Rock, offers 5R barrels, as well.

The way it's supposed to enhance accuracy is by not having lands and grooves opposite each other, which is supposed to deform the bullet less. Whether this makes a difference in most ARs is academic, IMO, as they're truly accurate enough to show that difference. My .260 Mega has a Bartlein 5R and is stupid accurate. My Grendel has a 5R Rock Creek barrel. I've seen plenty of VERY accurate rifles built with 4-grooves, though.

They clean a little easier, but you have to pay attention that the rod and brush is actually tracking in the rifling. The lack of the corner means it doesn't grab the brush as hard as a conventional rifling form.

5R is only one of a number of different forms available. Shilen has a "canted land" form, and as mentioned Bartlein and Krieger both have their version of 5R.

I own a few rifles with Faxon barrels. If I ever shot out my Nemo 20" .308 barrel, I'd get a Faxon replacement in a heartbeat. If a bolt ever take's the place of my precision LR308 in .308, I'd not hesitate to turning it into a carbine and use a Faxon carbine barrel.

You've clearly stated as fact that Krieger uses their version of Obermeyer 5R®. How do you reconcile your statement with this from Kriegers website:




The reason Krieger uses cut 4 groove in their barrels? From their website...


Curious... Is Faxon using 5R® with permission as its a registered trademark?

Apology aside, that doesn't bode well for Faxon. You're the director! One would expect you would know these things. Who actually makes Faxon barrels? Does Faxon actually manufacture anything or are you just a group of guys who really know little to nothing about firearms in an office somewhere taking orders and selling parts made by someone else? I think it's a fair question.
FYI I have (3) .308 AR builds going with your 20" heavy fluted barrels but I have to say I'm disappointed.

Wow...

Nope, not judging at all, just asking questions. I did a little reading of my own and see that Faxon Firearms is a spin off of Faxon Machining which is common. Lot of "firearm manufacturers" are spin offs of larger mfg companies. Many don't even have an FFL. The Faxon website talks about manufacturing upper receivers but doesn't say anything about manufacturing barrels. In fact, they do say, "OEM manufacturing from partner to product" so I take that as they don't manufacture barrels, that they have an OEM partner who does and that's fine too. I was under the assumption (my mistake) that you actually manufactured barrels and that's why I was surprised at the comment abut the 5R rifling. Now I understand.
I appreciate the apology and thank you for the courteous response.. It's not something you see too often these days. I like your barrels and promote them when I can.

I'd like to know if Faxon gun drills and rifles its own barrel blanks in house. If you don't, who supplies your blanks?