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AR Sponsor: bravocompany
Posted: 5/23/2005 8:34:21 AM EDT
Anyone use McPherson one piece gas rings in a Colt M16 Bolt Carrier?  What are the benefits over stock?

Thanks
Link Posted: 5/23/2005 10:04:45 AM EDT
[#1]

Quoted:
Anyone use McPherson one piece gas rings in a Colt M16 Bolt Carrier?  What are the benefits over stock?

Thanks



i belive there called mcfarland one piece gas rings  but anyhow    .. the answer to your question is that the gas rings that are on regular ar's could line up and short stroke the bolt ( the gaps in the rings )    i use all  1 piece gas rings on all of my ar's  m16's .. the ring almost goes around 4 times . just one less thing  to fail    
Link Posted: 5/23/2005 10:08:08 AM EDT
[#2]

Quoted:
Anyone use McPherson one piece gas rings in a Colt M16 Bolt Carrier?  What are the benefits over stock?

Thanks

Perhaps it's a solution without a problem, but for many, reassembling an AR-15 involves aligning the gaps in the gas rings to make sure they are as far apart as possible. We do this to avoid all sorts of problems and malfunctions. Finally, there's a solution that eliminates the need to adjust the rings' alignment, and lessens the chance of jamming.

How It's Supposed To Work
Upon firing, as the pressure of the gas generated by the burning propellant drives the projectile down the barrel and past the gas port, a small quantity of the gas is bled off through the gas port, gas tube, and bolt carrier key into the cylindrical section in the bolt carrier where it expands and drives the bolt carrier rearward. During the first rearward travel of the carrier, the bolt is rotated by the cam pin acted on by the bolt carrier cam slot. This rotation disengages the bolt lugs from the barrel extension lugs and so the bolt is unlocked. The carrier then continues rearward with the unlocked bolt. At this point, the gas used to drive the bolt carrier rearward is allowed to bleed out through two holes on the right of the bolt carrier.

The Problem
In order to install the rings on the bolt, they must be split and thus a "gap" on each ring is unavoidable. The problem arises because these gaps can become aligned, and cause too much gas to escape too early in the cycle. This can result in short-stroking and possibly jamming the rifle, so manuals and instructors enforce the proper alignment of the rings when reassembling the AR-15 rifle.

The Solution
The McFarland one-piece gas rings solves the problem of "aligned" gaps by eliminating the gaps. As a one-piece helical ring, you are guaranteed to never have the problem with the gaps.

Replacement
The 3 individual rings can be removed one at a time starting with the rearmost ring first. Lift one end of the open ring up and over the edge of the ring groove (towards the rear of the bolt) and then work the other end over. Repeat this for the remaining two rings, and you should be able to remove them without damage. As a single piece of metal, the McFarland ring is wound onto the groove on the bolt's rear. Start one end over the edge, and then work the remainder of the ring over that edge; the easiest way to accomplish this is without trying to turn the ring itself.

Ordering
If you're interested in trying these out, the McFarland rings can be ordered from Competition Specialties and are $1.75 for 1 - 4 quantities, $1.50 for 5-10 quantities, and $1.25 for 13 and up quantities. The shipping is included in the price. These prices are for the US sales only, outside the US you must call for shipping quote.

At those prices, every AR-15 should have the one-piece ring installed, and it's owner should keep a couple of spares around. While I have never experienced the dreaded "gap-alignment" syndrome, the theory appears sound and a little extra insurance can't hurt (at least I no longer have to worry about aligning, or mis-aligning, the rings each time I assemble the rifle!).

For more information or to place an order check out:

Competition Specialties
105 E. Cass, PO Box 451
Osceola, Iowa 50213
515-342-2011
800-369-4481
[email protected]
Link Posted: 5/23/2005 10:57:23 AM EDT
[#3]
They're not needed, but they do work.  IIRC, there were some stories of them "burning up" quickly or something like that, but I'd bet if properly lubricated when new, like any good ring that rides inside a cylinder, they'll break in just fine and seal for a long time.  I use a few of them without issue.
Link Posted: 5/23/2005 11:58:43 AM EDT
[#4]
i bought a set to see what the hype was.
they look as though it improves over the traditional three ring set up.  havenet had any problems with them and not enough rounds to know if they will hold up,
Link Posted: 5/23/2005 4:08:29 PM EDT
[#5]

Quoted:
i bought a set to see what the hype was.
they look as though it improves over the traditional three ring set up.  havenet had any problems with them and not enough rounds to know if they will hold up,



Im thinking of trying them out as well, and thats why I asked.  Thanks again guys for the info, I always get the help I need (save for alcohol intervention, but, you know)

Link Posted: 5/23/2005 4:09:00 PM EDT
[#6]
Edit

Link Posted: 5/23/2005 6:11:01 PM EDT
[#7]
I run a set in my SBR, and Paws M16.... Not had any problems.
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