A compact coyote rifle
Greg Dykstra of Primal Rights, Inc is a serious coyote hunter. While he mainly uses some laser-fast 22 caliber wildcats, he wanted to have a unique and dependable backup rifle to stuff into his Eberlestock pack in the event his primary rifle went down on a hunt. The 6mmBR cartridge is the poster child of inherently accurate cartridges. Excellent performance in a small package which offers outstanding barrel life as well as some very stable accuracy nodes.
"TS Customs has built me many rifles and hundreds of our customers Desert Tech barrels over the years. They all were infinitely capable and have worked extremely well for me. This 6mmBR rifle is no different. I used it as the host rifle during the development of our article on load development. The rifle performed flawlessly during testing, easily shooting tight groups without significant effort. Thanks a lot Travis & team, this is yet another example of why TS Customs is our precision rifle shop of choice!"
- Greg Dykstra
President - Primal Rights, Inc
First step on every custom action build is to snag a barrel out of the rack and get to fitting it up to the receiver. In this case we're spinning a trusted Benchmark 8 twist Medium Palma onto a Surgeon 591.
We hold the barrels in an adjustable 16C collet chuck that allows us to dial the bore into the center of the spindle. Use of round collets provides extremely rigid work holding which helps with surface finish, runout, and tooling life.
With the barrel dialed in, program for a Surgeon 591 called up, and work offsets established, cutting commences! The high pressure coolant makes it a bit tough to see what is going on in there but ensures proper surface finishes and chip evacuation.
Our threading cycle finishes the thread in .001" passes to allow perfect fitting of the threads to each individual receiver. We also record the thread wire diameter measurement and headspace of each custom action so that we can build a customer's future barrels without needing that receiver back in the shop.
Now that the receiver is fit up properly to the barrel tennon, we move on to the chambering process. A quick pass with our custom body roughing drill has the bulk of the material from the chamber removed and we load up the 6mmBR chambering reamer. By use of a hydraulic reamer holder with a positive stop for the reamer, we can record and retain tool length offsets for our entire reamer inventory. This just helps to speed up our process and reduce downtime at the machine for set ups.
Water-soluble coolant is pumped through the bore to keep chips flushed and ensure the best possible surface finish in the chamber.
Once proper headspace is established in the chamber, the barrel is inspected for runout and surface finish then lightly abraded to provide a slight bite on the brass to reduce bolt thrust.
To establish a top-dead-center orientation for barrel fluting and muzzle brake installation, the barrel and receiver get torqued together and marked.
Barrel fluting is completed in our 4axis vertical machining center. With this style of cutter, the operation is performed dry. The heat from the cutting is evacuated through the chips and tool life is enhanced by not having the hot/cold shock of the coolant spraying on it.
Fluting completed, we're back into the lathe for fitting the muzzle brake. The Thunderbeast CB brake has a top/bottom bias and requires timing. The barrel is indicated again true to the center of the spindle before turning and threading commences.
The thread shoulder for a timed muzzle device is left short and incrementally moved back to establish the proper timing.
In order to get rolling on this project in a timely manner, we grabbed a Manner's TF1A that was in stock but inlet for a Remington 700 short action with BDL bottom metal. It's going to require some work to get the Surgeon 591 and Surgeon detachable bottom metal fitting properly.
Clearance is cut for the bolt stop to get the action sitting down near the proper height.
To use a stepped pillar to hold the action at the right height for bedding, the existing pillar holes must be located and counterbored to hold the new step pillars. Using the stepped pillar design helps ensure stress free bedding as the pillars are torqued to the receiver and then placed in the bedding epoxy. The counterbores for the pillars are cut the proper depth to hold the action up off the clearanced action inlet so that the pillars are the only points of contact before gluing the remainder of the receiver into the stock.
The Surgeon 591 has a funky tang geometry that requires setting the action deeper into the stock than I care for. To avoid a mess of epoxy going places we don't it and some very unsightly bedding lines, we opted to build up the tang area of this stock with fiberglass fabric and resin. It's a bit ugly for now, but we'll be dressing everything together after bedding and before paint.
With the action and action inlet properly prepped, it's time to mix up some Marine-Tex and start the epoxy application process. Mixing the epoxy on a flat plate helps to alleviate the potential for pockets of air in the mixture. After mixing, the epoxy is carefully located in the inlet to flow where it needs to go when the action is set in the stock.
With the epoxy applied to the inlet, the barreled action is carefully slid in and secured with zip-ties. We have the pillars holding the height and alignment of the barreled action with the stock so the only job of the zip ties is to hold the action and pillars to the bottom of the pillar hole counterbores. I'm not concerned about bedding overflow with this job as it can be quickly cleaned up before the paint application.
After the 24 hours of curing, we pop the barreled action from its bed and see what we have inside. Remember that ugly tang area? Before pulling the action from the stock, some of the overflowed bedding needs to be knocked back to prevent any areas of bedding from breaking out upon removal of the barreled action. We start with a rough cut cabinet file and progressively work from finer files to a sanding block to blend the tang area of the stock to the receiver.
As expected, the bedding cured free of any voids and fully contacted with the action.
The bolt handle cut was also roughed and filled in upon the application of the bedding epoxy. You can see the original cut line from the Remington 700 bolt handle inlet. The bolt handle cut is now nicely matched to the straight handle on the 591.
The overflow bedding is also cleaned up from around the boss-style Surgeon bolt stop.
With the intention of using the Primal Rights 6BR conversion kits for AICS magazines, we have to open up the BDL cut in this stock to accept the Surgeon detachable bottom metal assembly. The stock is held in a fixture that locates off of the guard screw holds for alignment. Using pins through the pillars, the fixture is dialed in along the X-axis of the machine and stock to center the bottom metal in the stock.
Now that all the stock work and metal work is complete, it's time to get some paint on this bugger and get it wrapped up!
For the best strength and longevity of the paint job, the prep work is of utmost importance on both the stock and metal.
The metal is sanitized and degreased with warm soapy water and then bead blasted for proper adhesion of the Cerakote.
The stock has all pin-holes filled then is lightly abraded and thoroughly wiped down to be free of dust.
This stock is getting our "Mirage" camouflage pattern that we cut the stencils for in house. The pattern is based on 2 stencil layers with 3 different colors of the customer's choosing.
The barrel flutes on this project are also going to receive a contrasting color application to really make the paint job pop! Masking the flutes is a pain but very much worth it for the finished product.
Once all the paints are cured, the stencils and masking tape is peeled back to reveal the fruits of our hard work.
The little BR cartridges hold a special place in my heart and working on a very specialized project like this was certainly a ton of fun! When Greg and I collaborated on the 6BR AICS magazine conversion kits, we knew we would need the perfect host rifle to test the function of the magazine kits. While we didn't start with a perfectly matching set of parts to allow for an easy seamless assembly due to our timeline, having the right tools made the project much easier and was a good chance to exercise some skill sets that we don't utilize every day. What we ended up with is a truly awesome repeating rifle for the over-achieving little 6BR.