Today in Rooster’s man cave, I will be reviewing EM Precision Rifle’s newest 6XC build. This rifle was conceived by Shane and built by Steve for Shane’s wife, Kerri to use for PRS competitions. Kerri, I hope you’ve been in the gym, the Blueberry is a hefty girl, weighing in at a healthy 19 pounds! I have to wonder, is this payback of some sort?TEXT
Curtis Vector action
At the heart of this build is the Curtis Vector action. It’s a 3 lug design, allowing for a short 60 degree bolt throw which has proven to be really quick. It takes a little something to get used to at first – I’ve been a two-lug shooter all my life. Once you get onto it, you start to see some benefit of that faster cycling, especially when you’re under time constraint. This action also features integral 20 MOA rail and recoil lug. These are nice features, as there are no screws to come loose or lug misalignment risks when rebarreling.
Speaking of rebarreling, another neat feature of the Curtis Vector is the quick change capability. Loosen the set screw on each side of the action, screw the barrel out, and put another on. No barrel vise or torque wrench needed. It is possible to have pre-fit barrels done without the action in hand for fitting by the gunsmith. This may however require verification measurements for the gun smith.
The “DLC” coating on this action is a nice addition, though I think it may result in slight binding while running the bolt for a brief break in period. DLC stands for diamond like coating. I couldn’t find too much quick information about it other than it’s a very hard wear resistant coating that adds only microns to the surfaces.
I had some of this binding issue for about the first 40 to 60 rounds.Since I was having this minor issue, I applied some synthetic grease to the bolt body (something I don’t do if I don’t have to because of dirt accumulation on that grease) and ran it that way. It has since slicked up nicely and doesn’t exhibit that binding anymore. Now compared to something like a Defiance, the Curtis Vector is still a bit sticky, but nothing that would deter me from buying one.
During testing of this action, I found the bolt lift to be a little stiff. This is both good and bad – good in that it has a strong firing pin spring and solid sear engagement. Slightly irritating due to the fact that bolt lift is stiff enough to rotate the rifle off target if you don’t have a firm enough grip on it or if your bipod cant feature is loose, or if you’re in an unstable position. Really, the only thing a guy can do about this is learn to deal with it and grip the damn rifle. A big part of my issue with this is the way I’ve run the bolt for years – I’m the guy who does the finger flip to maintain shot-to-shot position. I find that full on grabbing the bolt like what’s required with this action breaks my position slightly, but it’s not something that can’t be overcome with some practice.
I like the bolt release on this action – instead of a vertical retaining pin like you see on many actions, the Curtis utilizes a horizontal pin and a vertically oriented bolt stop. The reason I like this is because the axial load from slamming the bolt back is taken by the stop itself rather than putting that load on the retaining pin which could bend the pin.
Feeding, extraction and ejection from this action have been flawless and very positive. The M16 style extractor is very strong and positive. I think it’s somewhere in between a mini M16 and a full size M16 type. Either way, this extractor / ejector assembly does a good job and is not lazy, just sort of flipping the cases out. It doesn’t, however, spit them out at mach 2, making you search for spent cases 12 feet away.
The Trigger Tech Diamond flat shoe….. Well, what can I say? It’s a very nice trigger! One of the best and that’s why EM Precision uses them in almost all their builds and that’s why I have as many as I do! It’s easily adjustable with a very crisp break that you really don’t even feel. I like that it has a nice positive wall just before it breaks. What else do you really need?
Then attached to the action is a Spuhr mount holding a Bushnell DMR II illuminated. Again, what can I say about the Spuhr that hasn’t already been said? This mount is the best on the market, hands down. And the DMR, while not the top level scope on the market, really does hold its own in capable hands and gets the job done for almost all shooting needs. It’s a tough scope, it’s reliable, very repeatable, and it resolves an image well. I have two of the older ones (one DMR and one ERS) that I am still perfectly happy with to this day.
IBI Barrel
Now, it’s said that a well made barrel and a good, straight chamber are the true keys to good accuracy. I can’t say as I disagree. The International Barrels 7-½ twist MTU contour barrel on this rifle has been nice to work with so far.
Through my 70 round load work up and acid test of the Blueberry, I cleaned it three times – once after five rounds, once after fifteen rounds and then again just before final load tuning. I scrubbed the hell out of it all three times because I only saw a small indication of copper (indicated by blue patches) each time. This is the first time I’ve personally worked with an IBI barrel and wasn’t sure exactly what to expect. Turns out that the copper came out with the first swab after leaving Wipe Out’s Patch Out solvent in the bore for about 15 mins. I went looking for more but failed to find it. Inspection with a Teslong borescope verified a nice clean, smooth bore. The machining and lapping in this barrel appears to be excellent………..and Steve did a pretty damn good job of chambering it too!
Steve tried something new with the cerakote on this barrel – he tried a titanium but it didn’t turn out like he had hoped (simply looks bead blasted) and the laser engraving he did, did not provide a lot of contrast. Once he receives this rifle back from me, Steve will be re-coating and re-engraving this barrel. These processes are done in-house at EM Precision, by the way.
Load Development
Load development with the IBI barrel proved to be a bit of a challenge, but I’m convinced this is due to the bullet used, and the design of the chamber. The throat on this reamer was designed for use with the 115 grain D-Tac bullet. The 110 grain Sierra MatchKing that EMP chose to use due to availability is a modernized design and does not share the same nose profile as the traditional MatchKings. The secant design of the 110’s requires a little more testing to get optimally-tuned performance. In order to touch the rifling in this Tubb-spec’d chamber, the bullet had to be seated out so that only about 60% of the bullet was in the neck of the case. I don’t like this for a dynamic application such as PRS, where ammunition needs to be rugged, so I had to find something seated deeper, with good precision.
Because of this, I conducted seating depth tests first, with a powder charge I felt to be reasonable according to the data I could gather regarding use of RL-16 in the 6XC. What I ended up with for a seating depth was 2.800” OAL, which is a .090” jump. It also liked a jump of .045”, but that meant less bullet in the neck.
An interesting note about the 6XC reamer that EMP uses, is that David Tubb designed this reamer specifically for use with Norma and Peterson brass. Peterson being the choice for this rifle. The design of the freebore, neck, and base dimensions are all specific for use with this brass. There is also a 6XC II reamer design available, which is specified for use with the Alpha brass that is currently available. The reason for this is because the case head dimension of the Alpha brass is smaller and would over expand in an original 6XC design chamber.
In the end, the 110 grain Sierra Match King performed well, as should be expected from Sierra.
Just a note that on the end of the IBI tube lives an Insite Arms Heathen brake. Definitely one of the best brakes out there and is made right here in Canada, just like the barrel it’s attached to.
MasterPiece Arms BA Competition Chassis
Now onto the MasterPiece Arms BA Competition Chassis. This is a very nice chassis. From cheek riser and length of pull adjustments to the thumb shelf on the grip, I found this chassis very easy to work with. Ergonomics are fantastic and even this old dog found that the thumb rest on the right side of the chassis actually proved to be very natural feeling – something that I’ve never before been a proponent of. I’m still not actually fully convinced, but with this chassis, it’s my preferred hold.
Also featured are the integrated bubble level and the Arca system machined right into the bottom of the forend. A bag rider was also added to this chassis, which made load development nicer.
Attached to the chassis is an Atlas V8 bipod via an Area 419 Arca adaptor mount. Now while I like the bipod and its features, the ball mount used in this assembly took some getting used to. In recent years, I’ve changed to a free recoil style of shooting from a bipod and this mount system does not support that very well. If you’re one who loads the bipod heavily, this mount works great and the spike feet on the bipod works well in dirt and softer surfaces. Put this system on concrete, a truck hood, a steel pipe barricade, etc. and it takes a different approach to perfect the shot.
So in closing, the EM Precision Rifles’ Blueberry 6XC is an excellent example of the craftsmanship that they’ve based their entire business on and the quality of the components that are available to them. This rifle is an outstanding shooter that I know Kerri will be happy and successful with.
And for anyone in the listening audience who is looking at having a precision rifle built, do not hesitate to contact Shane at EMPrifles.ca or call 780-690-7513. Tell him that Rooster and the First Focal Plane podcast sent you You’ll be glad you did.
Rooster
Leave a Reply