May 25th, 2019

Doh! Make Sure Your Ammo Fits Your Chamber!

Ruptured Cartridge Case

If you don’t match your ammo to your chamber, bad things can happen, that’s for sure. A while back, Forum member BigBlack had an experience at the gun range that reminds us of the importance of safety when shooting. He encountered evidence that someone had fired the wrong cartridge in a 7mm WSM rifle. The problem is more common than you may think. This Editor has personally seen novices try to shoot 9mm ammo in 40sw pistols. BigBlack’s story is along those lines, though the results were much more dramatic. It’s too bad a knowledgeable shooter was not nearby to “intervene” before this fellow chambered the wrong ammo.

7mm-08 is Not the Same as a 7mm WSM
BigBlack writes: “I know this has probably been replayed a thousand times but I feel we can never be reminded enough about safety. This weekend at the range I found a ruptured case on the ground. My immediate thoughts were that it was a hot load, but the neck area was begging for me to take a closer look, so I did. I took home the exploded case and rummaged through my old cases until I found a close match. From my investigative work it appears someone shot a 7mm-08 in a 7mm WSM. Take a look. In the above photo I’ve put together a 7mm WSM case (top), the ruptured case (middle), and a 7mm-08 case (bottom).”

The photo reveals what probably happened to the 7mm-08 case. The shoulder moved forward to match the 7mm WSM profile. The sidewalls of the case expanded outward in the much larger 7mm WSM chamber until they lacked the strength to contain the charge, and then the case sides ruptured catastrophically. A blow-out of this kind can be very dangerous, as the expanding gasses may not be completely contained within the action.

Can’t Happen to You? Think Again.
This kind of mistake — chambering the wrong cartridge — can happen to any shooter who is distracted, who places even a single wrong round in an ammo box, or who has two types of ammo on the bench. One of our Forum members was testing two different rifles recently and he picked up the wrong cartridge from the bench. As a result, he fired a .30-06 round in a .300 Win Mag chamber, and the case blew out. Here is his story:

“I took two of my hunting rifles I have not used for over 25 years to the range yesterday to get new scopes on paper, a .30-06 and .300 Win Mag. I had four boxes of old Winchester factory ammo (two of each cartridge), which had near identical appearances. I accidentally chambered a .30-06 round in the Sako .300 Win Mag rifle. It sprayed powder on my face and cracked the stock at the pistol grip. If I had not been wearing safety glasses I might be blind right now.

Safety eyewear glasses
You should always wear protective eyewear, EVERY time you shoot.

“I feel lucky and am very thankful for being OK — other than my face looks funny right now. I am also grateful for learning a valuable lesson. I will never put two different cartridges on the bench at the same time again.”

READ More about this incident in our Shooters’ Forum.

Permalink Reloading, Tech Tip 4 Comments »
May 25th, 2019

New Carbon-Wrapped Barrels from Helix 6 Precision

Helix 6 Precision Barrel carbon fiber proof research

Are you looking to shave POUNDS from your hunting rig or varmint rifle? There is a new option for folks looking for a weight-saving, carbon fiber-wrapped barrel. You’ve probably heard about Proof Research. That’s a good company that crafts good products. But now Proof Research has some competition — Helix 6 Precision in Washington State.

Helix 6 Precision Barrel carbon fiber proof research

Helix 6 Precision crafts button-rifled, carbon-wrapped barrels in both conventional and “pre-fit” configurations. Pre-fits are offered for Savage rifles as well as the Ruger Precision Rifle (RPR) series. These pre-fit barrels are not cheap. A 6.5 Creedmoor RPR pre-fit costs $995.00, while the Savage pre-fits are also just under a grand. The conventional barrel blanks cost $895.00 in .224, .243, .264, .284, and .308 calibers. The larger .338 caliber barrels run $945.00.

Helix 6 Precision Barrel carbon fiber proof research

While Helix 6 barrels do offer significant weight savings, the founders of Helix 6 say low mass wasn’t the number one design goal: “Accuracy was paramount and weight reduction was secondary. We’ve taken the industry’s most advanced carbon fiber engineering and pushed the technology further with our proprietary … carbon fiber process.”

The founders of Helix 6 Precision say they build some of the best carbon/steel hybrid barrels on the market: “Our unique carbon fiber-layup design dampens barrel harmonics for better accuracy. Each barrel is cut from a 416R stainless steel core, and carbon fiber-wrapped using the Helix 6 Precision’s advanced process. This creates match-grade accuracy barrels with high heat dispersion that are 30% lighter than a steel barrel of the same contour. The bores are … hand-lapped for precision accuracy.” Helix 6 claims its barrels are “lighter, stronger, and faster cooling than anything else available on the market.”

Myth vs. Reality — What Carbon Can and Cannot Do

Carbon fiber is formed using thin strands of carbon bonded together with a plastic polymer resin. The resulting material is very strong and light weight. There’s a reason Formula 1 cars are crafted with carbon-fiber composites. But is a carbon-wrapped barrel the right option for you? Here are some factors to consider:

Weight Savings — There’s no doubt that a carbon-wrapped barrel will weigh less than an unfluted stainless steel barrel with identical length and contour (outside diameters). Helix 6 claims a 30% weight reduction compared to a conventional stainless steel barrel. That’s significant.

Accuracy — Carbon-wrapped barrels are NOT commonly being used for F-Class or Benchrest competition. However, Proof Research carbon-wrapped barrels have performed well in PRS competitions in the hands of top shooters. So, we can conclude that carbon accuracy is good enough for the PRS/NRL tactical game, at least at the local club level.

Heat Dispersion — Carbon-wrapped barrel-makers claim their hybrid design disperses heat better than an all-steel barrel. Some independent testers disagree, saying: “hold on now — the carbon actually acts as an insulator, so more heat is retained in the barrel”. The jury is still out. One thing that is true is that the carbon barrels seem to generate less mirage from barrel heat. Ask yourself, “if less heat is coming OFF the barrel, where is that heat retained?” But the reduced mirage could be a function of the black woven surface which may release heat differently than polished steel.

Standard, Pre-Fit, and Custom Barrel Options
Helix 6 Precision barrels are available as pre-fit barrels for both Savage and the Ruger Precision Rifle in many popular long-range cartridges. Barrel blanks are sold in five calibers from .224 to .338. Helix 6 can also thread and chamber a barrel for any precision rifle. Helix 6 Precision also builds one-off barrels to fit individual needs.

Permalink Gear Review, Hunting/Varminting, New Product 2 Comments »