Vuurwapen Blog
15Apr/103

LWRC IAR Drop Test

Posted by Andrew Tuohy

I've been told that the following information is OK to release. It's pretty self explanatory. I removed the names of certain individuals, but the information is otherwise unedited.

Land Warfare Resources Corporation
Engineering Memorandum Engineering Memorandum
To: IAR Team
From:
Date Written: 8/8/07

IAR Drop Test – Summary

Purpose: The internal drop testing of the LWRC Infantry Automatic Rifle
was undertaken to determine how robust the Rifle and its component parts
and accessories are and simulates a drop from a rotary winged aircraft at
the maximum height a soldier might disembark from a rotary winged
aircraft or from the top of an Armored Personnel Carrier or Tank. The
purposed was also to find the best commercial off the shelf parts and
accessories that meet the requirements of the USMC IAR Draft RFP.
Testing Protocol: The LWRC Infantry Automatic Rifle was drop tested to
the USMC test protocol to ensure durability of the weapon and integral
accessories and furniture for internal product improvement prior to delivery
of LRIPS for Phase 2 of the Picatinny IAR Solicitaion. The weapon as
tested was 8.5 lbs. The weapon was dropped several times from all
angles starting with 12 o’clock butt down from 1.7 Meters (from the
buttplate) with the stock extended and locked in the 3rd position on the
buffer tube. The surface it was dropped on was concrete covered in 3/8”
plywood. For the purposes of the test, no optics were installed on the
weapon. The first drop being 12 o’clock butt down would test the viability
of the telescoping stock systems in the extended position. The testing
continued dropping the rifle from the 2, 3, 5, 6, 7, 8, 9, 10, 11 o’clock
positions from 1.7 m on the same surface. Back up rear Iron Sights were
in the upright position.
Pass/Fail: Success or failure of any component or accessory was judged
by whether the component was still operable after the drop testing. The
component could be damaged, but the weapon had to remain operable
and the repair of the replacement part must have been within the scope of
practice of a line infantry armorer.
Components Tested: Magpul CTR stock, Magpul MIAD, LMT SOPMOD
stock, A2 Gov Issue Pistol Grip, Latest Generation M4 Stock, VLTOR
EMOD, IAR Prototype Config, Matech Rear BUIS, TROY BUIS (sights are
purely educational as USMC has specified rear sight).
Failures Summary: All buttstocks failed the testing first drop except for
the VLTOR EMOD stock. The VLTOR EMOD stock survived all drops
from all angles and remained completely functional. Examination after the
testing revealed 2 hairline cracks from the corners of the steel locking plate
hole in the polymer. The stock remains completely intact and functional
and the engineering team has determined the stock would not need to be
replaced to serve the life span of the weapon. The Matech Rear sight
body cracked but remained functional. The Troy Sight broke during angle
drops and was rendered non functional. All other IAR Prototype
Components, and the weapon itself were inspected gauged and
measured, then test fired. The weapon underwent 48 drops (far beyond
the requirement) without any functional problems. There were no pistol
grip failures.
Land Warfare Research Corporation
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12Apr/1010

The 1% Solution for Customer Service Issues

Posted by Andrew Tuohy

1% of the cost of a rifle or upper receiver assembly.

Maybe that's too much to ask. I do know that margins are pretty low in this business.

What am I talking about? I'm asking manufacturers to spend 1% of the money they make from the sale of a rifle or upper receiver assembly on ammunition with which to test fire the weapon in question. Maybe spend .5% on ammunition and .5% on an extra employee to just look at stuff before it goes out the door. Poke it. Prod it. See if stuff falls off. Make sure that the right parts were used.

Evidence of sufficient test firing on a new production Spike's Tactical upper receiver assembly.

I've seen way too many issues recently that resulted from poor or nonexistent quality control at various manufacturers. It almost seems to be escalating. Take, for example, the DSA uppers that are still shipping out with rifle barrel extensions and M4 upper receivers, six months after they were initially made aware of the issue. For those that don't know, this combination creates a large divot underneath the left and the right feed ramps in an AR-15 upper, and can cause the weapon to stop functioning. I'd post a link, but DSA deleted the thread in their industry forum. It's too bad that they didn't decide to spend more time on quality control and less time on hiding their mistakes.

It's not just cheap, low end manufacturers, though - the new LWRC REPR has a problem with magazines. Not just one or two, but all of them. A significant number of new REPRs simply will not function with the supplied magazines, Magpul mags, DPMS mags, or Knight's Armament mags. Certain magazines fall out of the rifle after a few shots are fired. Now, LWRC decided to ship the REPR with CProducts magazines, but wouldn't it also make sense to test their rifle with the other magazines on the market? By the way, this rifle lists for over $3,000.

The Bushmaster ACR is currently selling for anywhere between $2,200 and $2,500. 1% of that would be a full magazine or two (at retail prices for brass cased ammunition). However, Bushmaster apparently sees fit to fire only three to five rounds through their rifles, according to a dealer which saw a fair sample size of ACRs. This extensive test program didn't stop at least one ACR from shipping with a loose barrel.

Colt fires a full 30 round magazine through every rifle that leaves their factory. Ruger also fires 30 rounds through every SR-556 they sell, after which the rifles are inspected thoroughly before shipping. Many other manufacturers have similar test programs, and the silence is deafening - that is, we don't hear about too many problems with Bravo Company or Spike's Tactical upper receiver assemblies. In fact, I'm told that so far, only one Spike's Tactical M4 LE upper has been returned for functional issues, and those were entirely ammo related: the owner was trying to shoot gun show reloads through the rifle. It should go without saying that such ammunition is low quality, and in this case, powder charges varied wildly, preventing the weapon from functioning properly.

So, is 1% too much? That'd be 15-20 rounds or so for the average upper receiver assembly, assuming that the manufacturers got a deal on the ammunition. It's climb pretty rapidly for a $3000 rifle. Maybe it should be limited to one full magazine. So, 1% of the cost of the weapon or upper, or one full magazine, whichever costs less. I don't think it's too much to ask. It's cheaper than shipping items back and forth, paying a guy to fix all the broken/nonfunctional stuff returned for repair, and lost sales due to bad publicity.

You're welcome to spend your money where you want, but I'll keep buying items from companies that care enough to carve a portion of their profit away in order to make sure that the customer receives a working product.

Update 4/14: I examined an ACR today and it appeared to have been test fired at least 20 times. That's a definite improvement. However, it doesn't explain the loose barrel as seen above.

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11Apr/100

AR-15 Gas Block Placement

Posted by Andrew Tuohy

Assembling an AR-15 is a fairly easy task. Even if one starts with everything disassembled, and has never done it before, the process should take no more than an hour or two, and requires only a few basic tools, a few specialized tools that are readily available, and a vise. However, it's also fairly easy to mess up.

One of the more common modifications to an already assembled rifle is the installation of a free float tube or free floating handguard that covers the gas block area. This is also a common task when assembling a rifle from parts. However, a very important step during installation is skipped over in many of the installation instructions I've seen: gas block placement.

The AR-15 rifle was originally designed with a fixed front sight base that held a metal handguard cap against a machined "shoulder" in the barrel. Standard handguards reside behind/inside this cap. A majority of AR-15s are sold with standard handguards...however, standard handguards are not normally used with low-profile gas blocks designed to be placed under a tube or rail. Therefore, when Joe Rifleowner removes the standard front sight base, handguard cap, etc to install his new free floating handguard, he tends to forget about that handguard cap, and slides the gas block along the barrel until it's against the shoulder in the barrel.

The only problem is, the majority of low profile gas blocks are manufactured in a way that allows them to be used with handguard caps, and sliding the gas block against the shoulder means that the gas port isn't properly lined up with the gas block, which holes the gas tube, which allows the weapon to function properly.

As a result, it's important to place the gas block about 1/16" from the shoulder on the barrel - give or take. The port in the gas block is oversized, leaving some room for error, but I can't count the number of rifles I've encountered that didn't function as a result of improper gas block placement. See the photos below for shots of proper gas block placement...

It's difficult to see due to the angle, but note that the gas block is not sitting against the shoulder on the barrel.

This gas block may actually be placed a little too far forward, but the gas port in the barrel is still "inside" the port in the gas block.

If you've been having "short stroking" issues after assembly of a rifle with a new gas block, you should definitely check gas block placement as a potential culprit.

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10Apr/100

Bravo Company 14.5" Midlength Accuracy Report

Posted by Andrew Tuohy

Just a brief note... I don't have a large number of groups shot through it yet, but from the bench using handloads, I was able to fire a number of 1.5-2MOA groups with the BCM 14.5" Midlength. Those groups were 10 shots at 100 yards.

The smallest was 1.46" (that was actually 12 shots because I apparently can't count) and the largest was 1.88". The load consisted of 73gr Berger HPBTs over Hodgdon Varget. I used a 10x Bushnell scope for those groups. For a more practical accuracy test, I was able to keep everything on a 6" plate at 100 yards, standing unsupported, using a Burris XTR-14. If you're more of a 3 shot group type of person, I don't think there was a single 3 shot group over 1". And most of the 5 shot groups were under or around 1", if that's your bag.

I'm now at just over 650 rounds through this upper - mostly cheap Brown Bear - and have yet to encounter any malfunctions.

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5Apr/103

PSA: Don’t Be an Idiot!

Posted by Andrew Tuohy

As they say, a picture is worth a thousand words...

Here are two cases I found at the range last week.

On the left is a properly fired 7.62x54R case. On the right is a 7.62x54R case that was fired in a rifle which was decidedly NOT chambered in 7.62x54R! It should go without saying that this is dangerous and can end badly. If you feel resistance when chambering a cartridge, do yourself a favor and check out the round before you try to fire it. If you don't believe me, watch as this guy - who clearly had ZERO experience with the AR-15 platform - manages to blow up his rifle due largely to his own incompetence. Now, that case didn't involve an improper caliber, to my knowledge, but it still serves to drive home the point that forcing a round into the chamber is likely to have negative results.

Update with another photo. I was thinking that it was .303 due to the new fireformed rounded shoulder, but I had to dig out some brass to check.