March 3rd, 2015

AR-15 Bolt Sheds Lugs — Can You Figure Out What Happened?

AR15 AR-15 Bolt lug shear damage Kaboom gas system pressure

Black Rifle Gone Bad…
Take a close look at this AR-15 bolt. Notice something missing — namely all the lugs? A healthy AR-15 bolt has seven (7) bearing lugs (plus an extractor hump). For all seven lugs to have sheared “clean off”, something serious must have happened to this bolt assembly. The folks at Brownells published this “lost luggage” image on Facebook to spur discussion. So, you AR experts out there — what do you think caused the problem here? Was it over-pressure, metal defect, headspace problem, gas system malfunction (or some combination of issues)? Post your theories in the comment section below…

AR15 AR-15 Bolt lug shear damage Kaboom gas system pressure

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March 3rd, 2015

Texas Triumph: 3600-Yard Shot with .375 CheyTac

3600 yard shot .375 cheytac texas

3600 yard shot .375 cheytac texas

They say “things are bigger in Texas”. Well shots are longer too. In this video, a shooter successfully hits a 1-MOA target at 3600 yards with a .375 CheyTac rifle. That required plenty of elevation to compensate for the bullet’s drop over its 2.045 mile trajectory. The shooter, Jim Spinella of New Jersey, needed a whopping 60.2 Mils of elevation (26.8 in rail, 22.6 in turret, 10.8 hold-over). Jim had to wait a long time to confirm the hit — with the metal gong situated more than than 2 miles from the firing line, it took the bullet 7.2 seconds to hit the target.

Big 350gr Bullets with a Wicked BC
The 3600-yard hit was made with CheyTac factory ammo using 350gr CNC-turned bullets. Spinella was impressed: “The ammo chronographed out at 3080 fps with velocity differences at no more the 7 fps, which was outstanding. We found the true BC over 3600 yards to average 0.810 (G1)”.

NOTE: You see three shots in the video, but Spinella took many more before a hit was achieved: “We peppered the 2 MOA area around the target with a couple of dozen rounds. We hit the rack the target is hanging on twice. This was a fun experience, and we took a lot of data away from it. We put a lot of work and planning into this in order to be in position to be lucky. So many things are ridiculously magnified at that distance. Every 1 mph change in wind [moves the bullet] about 6 feet. As the barrel heats up the velocity changes with it [and] 10 fps velocity differences, shot to shot, are almost 5 feet.”

This ultra-long-range adventure took place last September at the FTW Ranch in Texas. Spinella worked with a team of experts from Hill Country Rifles, builders of the custom .375 CheyTac rifle, to achieve a 3600-yard shot on a 36” round steel target. Hitting a target at 2.045 miles is no mean feat. That 36″ gong represents slightly less than 1 MOA at that range. A lot can happen to send a bullet off target during a 7.2 second flight.

Rifle: Hill Country Rifles custom .375 Cheytac,
Stiller Precision action, 29″ Krieger barrel
Optics: Schmidt & Bender 5-25X56mm PM-2 scope
Actual Measured Distance: 3606.41 Yards
Target: 36″ circular steel plate

Altitude: 2000 feet
Temp: 70 degrees
Elevation: 60.2 mil
Windage: 3.5 mil left

3600 yard shot .375 cheytac texas

CheyTac Caliber Comparison — .375 vs. .408
The shooter, Jim Spinella, prefers the .375 CheyTac to its .408-caliber Big Brother: “I shoot both the .408 and .375. Both are great ELR rounds and will get you out there a long way. In my experience, the .375 will get you out there a little bit further. My preference is the .375 Cheytac over the .408. This has nothing really to do with external ballistics. It has to do with fouling. My .408 will go from stellar accuracy to terrible between 40 and 45 rounds. It happens that quickly and accuracy returns after cleaning the barrel. I have never experienced this with the .375. After 100 rounds there is minimal copper fouling with the .375, but I clean around this round count. I don’t know why there is heavy cooper fouling in the .408, but it is common to this round and other shooters who shoot it regularly. That said, I lightly clean the .408 using Wipeout and go back to having fun with it after about 30 minutes.”

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March 3rd, 2015

New Official IDPA Steel Practice Target

At ranges across the country, on any given weekend, there are probably more IDPA matches than any other type of pistol competition. And now the IDPA has its own official steel practice target: the IDPA PT (Practice Torso). The new target, crafted by Utah-Based Action Target from 3/8″-thick AR550 steel, features a regulation torso shape with scoring zones. Green-colored reactive plates provide instant feedback. Notably, the target has no exposed bolts, clamps or brackets. The completely flat shooting surface reduces the risk of ricochets coming back at the shooter.

IDPA Training Target

The IDPA target’s reactive plates feature an innovative hinge design. “A lot of work went into the design of this target,” said Chris Hess, Action Target’s marketing manager. “Not only did we ensure that the torso dimensions of the target perfectly match IDPA regulation, we also created a new patent pending hinge design for the reactive plates that minimizes the number of parts needed and provides consistent reaction on every shot. This new design will soon be used on all of our reactive steel targets.”

New IDPA PT Target features innovative, Patent-pending hinge design.
IDPA Training Target

Two-time national IDPA champion Tom Yost helped develop the new steel target: “As a competitive shooter, this is exactly the kind of target I want to train with. Practicing on steel helps build muscle memory for accurate shots better than anything else because it provides instant feedback that you can hear and see.”

IDPA Matches feature “real-world” type scenarios, with guns drawn from cover.
IDPA Training Target

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