All things being equal, a longer barrel uses a smaller port.
Printable View
My socom profile ARPerformance barrel runs great. Shoots sub moa with pmc 54gr junk ammo. Ive been very happy with it and an H2 buffer.
I was specific on asking about a 5.56, but could have been quoted the port size for a 6.8.
Never even thought about that.
Great catch.
If you port barrels to run with true m193 and everyone uses cheap ammo how many call backs do you get and how many shipping charges do you eat?
The OP asked about shooting steel case Tula, it takes a .082 just like it does to run American Eagle and Remington UMC.
As a manufacturer I think it's better to port the barrels to run what works with a wider range of ammo and what most shoot not just the upper end and everything else short strokes.
How many times have you been to the range and hear someone say "this POS wont cycle"...and most are using the cheapest ammo they can find at Wally World. That same crowd wouldn't notice the m193 cases landing forward of 3 O'clock.
The high speed low drag crowd runs H2 buffers and heavy springs anyway. m193 drops right around 3-3:30 setup that way.
OP, what I told you is how we port the barrels. If you use cheap steel case they will run fine, if you use m193then you may need a H2 buffer to slow things down. As far as the accuracy thing, I'm just truthful. Some guys will buy a $200 lightweight barrel and then say "this thing wont shoot 3/4" with the cheapest ammo made, what's wrong with this thing".
Shoot 69 or 77gr SMKs with 24gr Re15 off a bench with a good trigger and scope and shooting skills and they'll shoot under an inch.
I have no idea how they will shoot with Tula off the tailgate of a truck using a $28 red dot from Walmart.
I owned an ARPerformance upper in 6.8SPC (a mid-length SOCOM barrel), and with factory ammo (Barret 6.8), the thing was a tack driver: sub-MOA as long as I did my part, and sometimes even when I didn't do my part.
When I buy from Harrison, I buy with confidence and without hesitation.
He answered my question and confirmed it before the masses.
Most of my ammo is brass cased M193 and Amer Eagle A223, but I do have a good bit of Tula and Silver Bear left over when this upper wore a Spike's Tactical 5.56 chamber CL barrel. I purchased this barrel after reading and others personal experience with ARP products. Not being a precision shooter with my AR, I would not expect TULA to shoot like match ammo.
Come on Fall so I can enjoy shooting more.
RDS is a Aimpoint H-1 2MOA on a Seekins fixed mount.
http://pic20.picturetrail.com/VOL132.../407108401.jpg
http://pic20.picturetrail.com/VOL132.../407189373.jpg
in any case, that's a good lookin stick!
I like the simple builds that can deliver.
I was thinking about using one of their 6.8 barrels on a new build.I know they have a pretty good rep with that crowd
Just sighted in my rifle with 16" scout barrel and five shot groups were right at 1" with factory SSA 110gr accubonds. Haven't had the change to roll some of my own loads but when I do I'm positive the group will shrink up. For the price, Harrison's barrels can not be beat.