22 Jan 02
I just completed a two-day Patrol rifle Course with a large PD on the West Coast. Everyone in the class used an AR-15, mostly Colts, a few Bushmasters.
Ammunition was generic Winchester. Each student expended nearly one thousand rounds.
We had a few failures to feed which were quickly reduced by the student, but no catastrophic breakdowns, save one. One student, a gunsmith no less, brought a tight-chambered (SAAMI), heavy-barreled, target rifle that started life as an AR-15, although it was difficult to tell by looking at it. It heated up and seized during the first hour of the class. We had to pull it off the line and give him a military surplus M-16, which worked fine for the duration. Any serious, autoloading rifle needs a NATO chamber. Only bolt guns should have SAAMI chambers.
A great contributor to AR-15 reliability is the chronic habits of:
(1) keeping the dust cover closed, and (2) keeping a magazine continuously in the magazine well. Those processes, in concert, plug all the holes and keep blowing grit and dirt out of the weapon. It should be standard procedure.
/John
DPMS AR-15s are manufactured nearby, and we had several in the course. All functioned well, except for the ones that had their triggers "customized." All of them experienced continuous functional distress One went down completely.
Lesson: PLAY GUNS CANNOT DOUBLE AS SERIOUS GUNS. Military rifles are pretty well set up for serious fighting as the come from the factory. Attempts to "customize" triggers and "accurize" the system are ill advised if the weapon is to be put to serious use. Increases in accuracy from such modifications are negligible, but compromises in reliability are disastrous, as we saw this weekend.
/John
13 Aug 02
Sage rifle comments from a friend in the Philippines:
"AR15's have always been popular here. They were made locally from 1983-1987 under license from Colt. Most are still in active service. The black market is the ONLY source for these rifles, as none can be transferred legally.
Connected (‘qualified') civilians are allowed to possess and even carry them
outside their homes. Many are thus ditching their MP5s and UZIs. Pent up demand, coupled with news photos of US soldiers armed with M4s during their local exercises, has driven the cost of these black-market ARs through the roof.
In the last few months, among my friends I've seen every conceivable permutation of this rifle! Anything from an eight-inch barrel to a twenty-four inch, heavy barrel, with every imaginable gimmick glued, screwed, taped, or pinned onto them.
You Americans are not the only gimmick-happy race in the world! Most folks here too just can't seem to be content with any species of ‘stock' rifle. They
predictably load them up with widgets until they weigh more than an M-14.
‘Accuracy' jobs are just as common. Like you, I've seen nearly all of these
modified guns malfunction with monotonous regularity. Curiously, their
demonstrated unreliability is usually lost on their naive owners. Some things
never change!
Standing in stark contrast are full-time military people I know whose lives
literally depend on the reliability of their individual weapons every time they
go on an operation. Most of my military friends have been on many. Their M-16s are all stock, ‘plain vanilla' as you would say. These men have survived
numerous, live contacts with the enemy. Their rifles work, every time. Those
with unreliable rifles are no longer with us!"
Lesson: Take this advice from the mouth of one who knows. You need to be serious about your "serious" weapons.
/John
27 Nov 02
On the AR-15/M-16/M-4/etc from a friend who manufacturers guns:
"As a result of heavy use, M-16 upper receiver aluminum forgings can begin
to 'oval out' where the barrel is installed. Accuracy suffers greatly, and the
weapon can come apart.
On the lower receiver (also an aluminum forging), the holes for the hammer pin are also famous for 'ovaling,' to the point pins walk out.
The M16 bolt also has problems. Locking lugs next to the extractor begin to
crack around 6,000 rounds, especially if the rifle is shot on full auto. The
other point of bolt weakness is the cam pin hole. The bolt breaks at the cam pin hole between 6,000 and 10,000 rounds.
Most civilians will never shoot their AR15s enough for any of these problems to develop. However, your students who attend course after course should be inspecting their arms regularly.
Our government, fully aware of the forgoing, has decided to get bids on (can you believe it?) shot counters, so they can know how many rounds have gone through each rifle. This is ridiculous! It is time for a long-overdue change."
/John
10 July 01
On urban rifles from a LEO friend in Wisconsin:
"A couple of our officers recently graduated of the Urban Rifle Course at Thunder Ranch. They both independently made the same observation:
Many of their fellow students showed up with bipods, various battery-operated sights, attached flashlights, lasers, and bewildering sling systems, all attached in miscellaneous ways to their rifles.
WITHOUT EXCEPTION, those people had taken all that junk off their rifle by the morning of the third day. All those gadgets had either broken, fallen off, ran out of juice, or made the rifle so heavy and unwieldily as to render it useless."
Lesson: Don't load up your guns with gimmicky junk. Instead, load up yourself with knowledge, righteousness, and experience. The latter will serve you far better than the former.
/John
Good friend, Giles Stock, made a wonderful and revealing presentation on 223/5.56 rifle chambers. Rifles can feature NATO or SAMMI specification chambers. As a rule, military rifles have NATO chambers, and recreational rifles have SAMMI chambers, but there is some overlap. For example, Ruger's Mini-14 has been made both ways!
NATO chambers have a long lead. SAMMI chambers are tighter and have a short lead. SAMMI chambers are designed for increased accuracy, but will yield dangerously high pressures in guns using military ammunition and/or which are subject to high volume shooting. Under such high pressures, primers will typically blow out backwards, fall down into the trigger mechanism, and cause the rifle to stop working. I've surely seen this on the range.
Bottom line: SAMMI chambers are for the kiddies. Any serious rifle needs a NATO chamber. Robinson Arms rifles come with NATO chambers, as do most of the others, but one needs to check.
Alex Robinson adds:
"If you use a SAMMI chamber in an autoloading rifle, you may overpressure it and blow it up when shooting rapidly. The tighter, shorter lead slows down the bullet substantially as it is trying to leave the case. When rifles are red hot from rapid shooting, the resultant pressures increase dramatically. In these situations, you need to get the bullet out of the case and down the barrel ASAP.
I never suggest using a SAMMI chamber on anything but a bolt action rifle. Anyone who tells you otherwise hasn't shot enough."
He ought to know!
More later.
/John
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