Archive for the 'AR-15s' Category

I was actually a little surprised at the results with dry wall.  I also expected a little different results from the heavier rounds (I expected the rounds greater than 70 grains to expand a bit more since they are “open tip”).

I’ve actually seen this failure, but only once (not in my gun).  I and the other shooters were all puzzled for a while, eventually got it cleared, and went on with the day.  We did everything he said we would do, including trying to remove the upper (but the bolt was back in the buffer and we couldn’t).  But I wish I had seen Jerry on this failure before that day.

I guess I’m a little surprised.  He “cleaned” his gun completely without the use of any solvent.  I’ve never cleaned a gun of any kind without Hoppe’s No. 9 at the ready.

Ammoland.

Through the first half of the Twentieth Century, military rifle cartridges were all between 6.5mm and 8mm (25-31 caliber), in order to achieve an acceptable rifle/ammunition compromise that balances:

• Adequate range
• Adequate penetration
• Accuracy
• Manageable recoil
• Weight
• Bulk
• Durability
• Overheating
• Barrel length
• Barrel life
• Magazine capacity, and
• Terminal effect

Those twelve issues represent competing, unavoidable trade-offs confronting weapon and ammunition designers. It is not possible to “adjust” any one of those without affecting all the rest. Go too far in any one direction, and you immediately run into deal-busting troubles!

That weapon design is a perpetual tradeoff is certainly true.  There is no debating that point.

In the first half of the Twentieth Century, horse-mounted cavalry units persisted, although mostly obsolete by the end of WWI.

However, with cavalry still a military consideration, “adequate terminal effect” implied an ability to take-down a horse with one shot!

In our modern era, with horses no longer a consideration, 5.5mm (22 caliber) bullets (5.56×45 NATO, 5.45×39 Soviet, 5.7×28 FN) have emerged and are considered (by some) appropriate chamberings for modern, military main-battle rifles, but there is far from “universal agreement” on that!

Inadequate penetration and inadequate range have been persistently (since the 1960s) cited as critical failings with this modern generation small-caliber military cartridges.

Interminable technological attempts to address these two issues have failed to silence critics, including me.

And so the point of the article was what – that Farnam is still an opponent of the 5.56mm cartridge?  We needed to be reminded of that?

So just to float the same point I’ve made before, Farnam leaves out the most important point in the discussion, and that is military doctrine.  Doctrine leads to or produces tactics, and tactics produces weapons design, not vice versa.

There is no point in rehearsing the doctrinal changes that occurred to bring about the advent of the 5.56mm cartridge.  But it is sufficient to say: that the use of fire and maneuver tactics (e.g., squad rushes), the reliance on crew served weapons for longer range combat (because more than 80% of enemy killed occurred throughout military history from crew served weapons, not rifles), and the reliance on DMs for even longer range shooting (those who have been specifically schooled in that science, and have been issued the weapons and gear for it), is legitimate military doctrine.

Farnam’s objections not withstanding.  In a perfect world in which Soldiers and Marines didn’t have to wear body armor because they were never shot at, they were in perfect shape, they didn’t have to leave the line at 100 pounds of kit, and the U.S. military had unlimited resources, time and money, everyone could carry rifles that weighed twice as much and carry ammunition that weighed twice as much.

My only comment is that trigger break weight will be a function of where you put your finger because the trigger itself is a lever arm.

Joefour, this one is for you.  It’s you and me, Stoner versus Kalashnikov. Eugene wins every time.  Stoner rules, Kalashnikov drools.

Brownells on AR gas and buffer systems.

Eh, okay, whatever.  I accept what they’re saying for nominal applications, but for fine tuning I think there is more to it than that.

On another but very interesting note, Brownells is assisting in the Covid-19 analysis.

Brownells, an 80-year-old, Iowa-based online firearm, and firearm accessories supplier has joined forces with Folding@Home to lend its excess computing power to help combat the COVID-19 virus sweeping across the globe.

Folding@Home is helping with an international effort to understand the molecular structure of the virus in hopes of finding ways to defeat it. Folding@Home has called on individuals and companies with excess server space and computing abilities to help execute computer modeling simulations to help speed up an otherwise huge and lengthy task.

“Our IT team learned about the Folding@Home project and their work using computer modeling to better understand the molecular and protein structure of the virus,” said Brownells IT Director Curt Graff. “We are committed to helping protect our country by virtue of our personal protection and sustainability products, but we see this as a way to support the international community in a time of significant need.”

Brownells anticipates it will donate at least 1,300 hours to the project and run approximately 200 simulations on behalf of COVID-19 research.

Okay, so this is really cool, and some of you may be confused, so I’ll do my best to explain this.

Processor speed hasn’t significantly increased for many years, but the ability to utilize threaded calculations has.  Many PhD theses have been written on “massively parallel” computing, and most high performance computer codes today (that require billions of calculations) are written to be able to utilize thousands of cores (written, of course, for HPC, or UNIX High Performance Computing clusters).  In my recent work, I’ve used more than 1400 cores for approximately 20 wall clock-hours for each simulation.  That requires a lot of computing power.

Why on earth would Brownells have this kind of computing capacity, you might ask?  I suspect, but I don’t know with certainty, that Brownells has these capabilities because of CFD (computational fluid dynamics) and FEA (finite elements analysis) for ballistics and bullet design.

Someone could prove me wrong by calling Brownells and discussing this with them, or I can.  It might be interesting to find out.  If they don’t have it for those reasons, they have it for some other reason, and it would be interesting to know.  A number of large corporations who do advanced computing have access to thousands of cores, as do the national laboratories (who have the largest computers).  It was a bit surprising to me that Brownells has access to the kind of computing power that these computer codes will need.

But I think it’s cool.  Does some reader want to call Brownells and let us all know?

Either way, it’s nice to see that a firearms giant is helping in the battle against Covid-19.  Hey, if Brownells helps find a treatment, do the gun controllers promise not to use that treatment?  After all, they wouldn’t want to be in bed with the gunners, would they?

Ammoland has the details.

Coming in at 6.8 pounds, I really like the lightweight handguard.  The price point seems right too (MSRP: $1100), and I think it’s a good addition to their stable given the usual unavailability (and high cost) of 458 SOCOM and the much higher availability (and lower cost) of 450 Bushmaster.