Sunday GunDay: 6XC II Precision Rifle for PRS and NRL Comps

Rifle Crafted by PremierAccuracy.com. Inset 6XC II photo by 6mmAR.com.

With all the buzz about the 6.5 Creedmoor and its 6mm Creedmoor little brother, some folks forget that we’ve had an outstanding mid-sized, Across-the-Course cartridge for a long time — the 6XC. Pioneered by 11-time National High Power champion David Tubb, the 6XC has won national High Power championships, excelled in mid-range prone matches, and performed great in the varmint fields. It has also been used successfully by many Precision Rifle Series competitors. It’s no wonder — the 6XC has less recoil than a 6.5mm Creedmoor, there is a great selection of superb 6mm bullets, and Peterson 6XC brass is high-quality and reasonably priced ($69/100) from DavidTubb.com. Fine Norma 6XC brass is available from Grafs.com.

PRS Rifle with Modern 6XC II Chamber
Forum member Grimstod posted this new 6XC II rifle in our long-running Pride and Joy Rifle Thread. Grimstod notes: “These 6XC Gen IIs seam to be a hot commodity lately. This one is for PRS. It features a Premier Accuracy Atlas action made by Kelbly. The bolt and heavy-taper, fluted barrel are Cerakoted to match. I really like the ejectors on these Atlas actions. The stock is a KRG X-Ray painted in Premier Accuracy exclusive colors. The Kelbly Atlas action does not have any modifications. So far every Kelbly action we have tried has had perfect timing and trigger fall. We have been supper pleased with them. I look forward to using a lot more of these excellent actions.”

What is the 6XC II you may ask? That designates a 6XC with a chamber dimension optimized for Norma brass. It turns out that Norma brass is a bit bigger at the bottom than the 22-250 brass from which the 6XC originated. Robert Whitley of 6mmAR.com has created two new JGS reamer specs that fit the Norma brass perfectly, improving feeding and extraction. Here is Robert’s Report:

The 6XC II Chamber — Upgraded for Today’s Norma 6XC Brass

by Robert Whitley of 6mmAR.com
The 6XC II Chamber works perfectly with the Norma 6XC brass and resolves the “sticky bolt lift” issue. The original 6XC chambering was designed based off the usage of 22-250 brass which typically has a web diameter in the range of .461″-.463″. The area of the chamber just forward of the web on the original 6XC chambering was .4695″ which left plenty of clearance.

When Norma 6XC brass became available Norma appears to have developed the base of the case from the .308 Winchester line of cases which have a larger web diameter. The web diameter of the Norma brass typically measures right around .4685″ which leaves almost no diameter clearance.

As shooters would use Norma 6XC brass in an original 6XC chamber they typically would experience “sticky bolt lift” due to the lack of clearance and the fact that the large web diameter of the brass prohibited the re-size dies (no matter how small the base diameter was) from squeezing the brass down enough to create sufficient clearance. The 6XC II chamber resolves this issue. You can order 6XC II sizing dies from 6mmAR.com that work perfectly with this re-designed chambering. 6XC II die sets are in stock now — call (215) 348-8789 to order.

6XC II Long Range Reamer (Throated long for 105-115gr Bullets):
The 6XC II-LT reamer below is throated long to keep the full bearing surface of 110-115gr bullets forward of the neck/shoulder junction of the case. Note, 6mmAR.com has also developed a shorter-freebore version for 6mm bullets with shorter bearing surface. SEE shorter 6XC II Reamer Print.

6XC II Chamber and Sizing Die Combo:

- Resolves the “sticky bolt lift” problem shooters experienced using the Norma 6XC Brass in the original 6XC chambers.

– Chamber accepts all 6XC brass or ammo with no modification. Take your existing 6XC brass or ammo and use it without issues.

– Works well with existing Norma 6XC brass, or 6XC brass made from re-formed Winchester and Remington 22-250 brass.

– 6XC II Sizing dies and die sets are available from 6mmAR.com and in stock.

If you are looking for someone to chamber your rifle or re-barrel an existing rifle in the 6XC II chamber, Fred at Sabreco, Inc. in Skippack, PA, (610) 584-8228 can help you. He has the reamers for the cartridge as well as the head space gauges for the cartridge, and has had extensive experience chambering many barrels and rifles.