This was one of my first custom rifle builds and I wanted to build a very versatile rifle capable of reaching out to a long distance, while still being relatively compact and maneuverable. I settled on .300 Winchester Magnum for the chambering as I really like the variety of bullets available in .30 caliber and I wanted a gun to go beyond 1000 yards with. The nice thing about .300 Win Mag is that it makes really good use of some of the super-heavy high-BC .30 cal bullets like the 230 grain Berger Hybrid Open-Tip Match bullets which have an .711 G1 ballistic coefficient! I have a preference for shorter barrels, so I wanted to make this thing as short and handy as I could, while still keeping enough velocity to make those seriously long-range hits. I decided on 21″ inches total as I could justify to myself the 140 ft/second drop in velocity using an example load of 3268 ft/second at 26″ using a 165 grain bullet. In fact, thinking inversely, I don’t think I’d be able to justify adding nearly another half-foot to the rifle just for a measly 140 ft/second.
The barrel I chose was a Shilen Chrome Moly Match Grade barrel with a heavier contour. One advantage of a heavier barrel is that it will flex less under firing which the barrel being as short as it is compliments nicely. Of course a heavier barrel will also radiate heat more easily due to the higher surface area and heat up more slowly due to the larger mass distributing the heat throughout itself. I decided that it may behoove me to replace the recoil lug with one that has a bit more mass. The one I chose was a Badger Ordnance Maximized Recoil Lug which is a .312″ thick lug that has less tapered edges and therefore a larger surface area. This promotes better dispersion of recoil force from the action to the stock. When performing machining operations on the barrel, the shank had to be cut to accommodate the thicker lug. The chamber was reamed using PTG reamers with the final dimensions being very tight, just .001″-.0015″ over minimum diameter. This was verified with a cerrosafe chamber casting and a micrometer. The muzzle was cut to 11 degrees, a very common angle among precision rifles. The action was fit to the barrel without any problems, and the head space checked with go and no-go gauges. It passed its headspace check, and so I went to fit the barreled action to the stock.
The stock that I decided on was a McMillan A5 fiberglass stock with the dual thumbwheel cheek height adjustment and removable spacer length of pull adjustment. McMillan makes some great stocks, and their models have been used on the Marine Corps’ M40 sniper rifles for many years. However, the stock wouldn’t fit this action right out of the box, so some modifications had to be made. The trigger guard I chose to use was the Badger Ordnance M4 long action which is a really heavy duty piece of kit that you could probably pound nails in with, and the stock had to be made to fit it. It was close enough though that only minor fitting was necessary and I used a two-part epoxy to bed it in solidly. The barrel channel had to be widened on a mill to accept the larger diameter barrel and final fitting was done by hand with a special barrel channel shaping tool. The recoil lug section had to be widened and lengthened to fit on the mill and the barreled action was then bedded into the stock to ensure a good action-to-stock fit with the free-floating barrel.
I have a preference for a larger, more easily graspable bolt knob, so I decided to make my own the way I wanted. First, I turned down the bolt knob to the appropriate size and then threaded it with a die. I prefer to turn the knob itself down instead of cutting it off and then turning down and threading the handle where the knob connects because I can get a longer overall length on the handle if I don’t chop it. For the knob itself I took a bit of stock and turned it on the lathe with 40 degree angles at each end with the handle end having a longer taper down. I turned it down in about 1/16″ sections along its circumference and knurled it for a more positive grip. The handle end was then drilled out and tapped to fit over the turned and threaded bolt handle. The trigger I chose was a flat-shoed Timney trigger with a 1.5 to 4 pounds adjustment range. This was a pretty wide trigger, so it required some modification of the stock to fit through the trigger guard. It was a pretty close fit, and in the future I would probably not use so wide a trigger in a rifle with this configuration.
At this point I had sort of a theme going, so I decided to get a steel Badger Ordnance 20 MOA scope rail for mounting optics. That was tightened down to the proper inch-pounds torque setting and loctited in. Now the rifle was set for test firing, so I brought it out to the range and put a few rounds through it. The brass was examined for abnormalities, and found to be properly sized. Below I’ve included an example group shot out of this rifle at 200 yards that measured 1/4″ which is equivalent to 1/8th of one minute of angle. This rifle can ring steel at 1000 without issue and I’m confident it’s a 1500+ yard shooter. If I were building myself another long range rig today I’d probably do some things differently, but it was a fun build and I’m happy with how it came out.