Piercision Rifles .300 WSM Build Review

After several years of reading about the .300 WSM on Long Range Only (LRO), I finally decided to build one. The popular favorite was the Alex Wheeler reamer designed around the 185-grain Berger Juggernaut, offering excellent ballistics and terminal performance on game.

Long story short, I spoke with Alex—an outstanding gentleman—and started looking for an action and barrel to send him. Alex explained that the stock work and final assembly would need to be completed by another gunsmith because of his workload. I also spoke with Ryan Pierce at Piercision Rifles. Ryan had an action that would fit the build, but his reamer was set up for the 215-grain Berger LRHT. After comparing the ballistics and considering my timeline for when I wanted the rifle completed, I decided to go with Ryan and began the ordering process.

A Couple Things Worth Noting

Ryan builds complete rifle systems, so he requires the scope and rings in hand during assembly. One reason is that he wants complete control system and over the installation process to eliminate stress on the scope caused by improperly fitted rings. Ryan beds the scope into the rings, explaining that he has seen numerous cases of rings slipping or uneven torque causing scope malfunctions. Bedding the rings eliminates those issues.

Another noteworthy detail is that Ryan’s reamer is designed around a neck-turned brass system. He uses an AutoDod to turn both the inside and outside of the necks, ensuring complete uniformity with ADG brass. I purchased brass from him, and he turned all of the necks before shipping. ADG brass should easily outlast a barrel with proper care, so while it was an added expense, it was a relatively small investment for quality brass that will stay with this barrel throughout its life. Ryan also supplied the proper AMP annealer code, eliminating the need to sacrifice a case to determine the setting.

Rifle Specifications

• Manners Pro Hunter Adjustable stock
• Defiance ANTIX Medium action (Nitride)
• Hawkins XM DBM
• TriggerTech Primary
• Benchmark Carbon barrel, 22″, 1:9 twist
• Nightforce NX8 4-32×50 MOAR FDE
• Nightforce Ultralite four-screw rings
• Unloaded weight: 8 lbs. 12 oz.

Ryan was also helpful in providing a starting load and estimated velocity before I took delivery. His recommendation was ADG brass, Federal GM210M primers, approximately 63.0 grains of Vihtavuori N555, and the Berger 215 LRHT at roughly 2,700 fps. He also supplied a dummy round built with brass and bullets I had sent him. Normally I prefer to perform all of my own load development, but I was short on time and decided to take the easy route.

Gunsmith Review

Ryan answered every question I had and was responsive throughout the process by both phone and email. Once I sent him my scope, he completed the final assembly and shipped the finished rifle to my FFL.

Rifle Work-Up

With the rifle in hand, I loaded several batches using 62.0 grains of N555 and Berger 208-grain bullets to establish my zero and begin breaking in the barrel. I generally don’t overcomplicate barrel break-in and simply wanted to get rounds down the tube.

The Manners Pro Hunter stock fits me very well, but at only 8 pounds 12 ounces, it is a lightweight hunting rifle and tends to move around if held too tightly. I found that it shoots best off a bipod with very little pre-loading. I also spent time shooting it from a backpack and tripod during the break-in process.

My initial velocities were around 2,550-2,580 fps with both the 208- and 215-grain Berger bullets. Conditions were approximately 45°F at 1,500 feet elevation. Initially, I was concerned the barrel might be slower than expected, but the rifle was already producing consistent ¾-MOA groups. I quickly learned that this rifle is very sensitive to shooter input. It performs best when it isn’t pulled tightly into the shoulder. Recoil is sharp but completely manageable, especially with my Thunder Beast Arms Ultra 5 suppressor, which stays on the rifle full time.

During my second range session, I stretched the rifle to 300 yards and fired a five-shot group measuring 1.3 inches outside-to-outside. The carbon barrel does warm noticeably after five rounds, but I have not observed any point-of-impact shift or group walking. To maximize barrel life, I avoid shooting my hunting rifles excessively fast or allowing them to become overly hot.

As load development progressed, I generally fired four five-shot groups with ample cooling time between strings for both the barrel and suppressor. This gave me additional trigger time while allowing me to learn exactly how the rifle preferred to be shot.

As the round count increased, velocity slowly climbed. I settled on 63.0 grains of N555, producing approximately 2,600 fps. Multiple range sessions produced groups with bullets touching and consistent sub-¾-MOA accuracy as everything continued to settle in.

Eventually I had the opportunity to stretch the rifle at a friend’s range, where targets extended to one mile. Conditions were challenging, with sustained 14 mph winds and gusts reaching 21 mph.

The 980-yard target was calling my name.

After letting everyone else shoot, I decided it was time for a true cold-bore shot. I grabbed the .300 WSM out of the truck, dialed 29.25 MOA, settled behind the rifle, and sent one.

Impact.

The rifle was clean, cold, and running off a generic 2,600 fps ballistic profile with approximately 120 rounds through the barrel. I was pleasantly surprised by the first-round hit at 980 yards, especially considering the barrel still wasn’t fully settled and load development was ongoing. At that point, the rifle has potential.

I continued bringing the rifle to every range trip, averaging 10-20 rounds per session while refining the load as velocity stabilized. Unfortunately, much of this process occurred during the summer, so high temperatures, humidity, and heavy mirage kept round counts relatively low. I typically cleaned the rifle after every range session, and as the barrel accumulated rounds, copper fouling became progressively easier to remove.

The ADG brass continued to perform exceptionally well. I sized with a Bullet Central Micron sizing die using both .330 and .335 bushings to maintain consistent neck tension.

By August, velocity had stabilized at approximately 2,650 fps. While I would certainly prefer 2,700 fps with the 215 Berger LRHT, the rifle consistently shoots around ½ MOA at 2,650 fps. Based on my ballistic calculations, that gives me roughly 750 yards of effective range while maintaining over 1,500 ft-lbs of energy.

More recently, I experienced a slight drop in velocity. Conditions were approximately 75°F with extremely high humidity coming off the surrounding corn fields, leaving a noticeable haze hanging in the air. Three rounds at 300 yards over the chronograph recorded 2,638, 2,637, and 2,634 fps. I’m not entirely sure why velocity dropped roughly 15 fps. Humidity may have played a role, although that alone shouldn’t account for all of it. The group also printed about three inches high and measured just over 1.5 inches.

Rifle Review

Ryan built an excellent rifle using high-quality components and outstanding craftsmanship. The rifle has performed almost exactly as he predicted and has settled in where expected. I couldn’t be happier with the quality of his work.

The Less Glamorous Details

This rifle requires neck-turned brass, either prepared by Ryan or with an AutoDod. You can purchase an AutoDod for roughly $3,000 and do the work yourself, or simply pay Ryan about a dollar per case to turn your brass. Considering the barrel will almost certainly wear out before my 100 pieces of ADG brass do, the cost per shot is very reasonable.

The primary limitation is velocity. A 22-inch hunting barrel simply gives up some speed. Personally, I’d like to see at least 2,800 fps, but that would require either more powder capacity or a longer barrel.

Even at 2,650 fps, this rifle remains a very capable hunting setup. For elk, I consider about 750 yards to be the absolute practical limit. At 700 yards, the bullet is still carrying roughly 1,858 fps and 1,648 ft-lbs of energy. For a lightweight mountain rifle, that’s more than acceptable, and I’d rather close the distance whenever possible anyway.

This rifle fills the gap nicely between my .308 Winchester and my .300 PRC. For its intended purpose, it does exactly what I wanted it to do.

That said, I still find myself thinking about eventually switching to an Alex Wheeler chamber built around the 185-grain Berger Juggernaut. Based on everything I’ve read, the 185 Juggernaut appears to be a particularly efficient match for the .300 WSM’s case capacity.

As of August 30, 2026, the rifle has 197 rounds through it. I’m looking forward to stretching it back out once the crops come down this fall. I also have both mule deer and whitetail tags in my pocket, so this rifle should finally get some time in the field.

Overall, this is a high-quality rifle built with excellent attention to detail. Even so, I’m still intrigued by the idea of a future barrel chambered for no-neck-turn brass and optimized around the 185-grain Berger Juggernaut.

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