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New Stag Arms Model 8 (Piston)

Stag Arms's newest AR-15 is the piston operated Model 8 carbine.

Model 8 Piston Carbine

Stag have not released much information about the rifle. It looks much the same as their M4-style Model 3 carbine. I am not sure if the piston system is their own design (if you can identify, please do in the comments). It looks like it could be a long-stroke design, but I am not sure. UPDATE: See below.

Piston system can be seen when upper handguard is removed.

Specifications
Caliber 5.56mm NATO
Upper Forged and Mil Spec
Operating System Short Stroke Piston
Sights Midwest Industries Front & Rear Flip Sight
Barrel 16" Chrome Lined 1/9 Twist
Magazine Standard AR-15
Stock 6 Position Collapsible
MSRP (Price) $1,145 (standard model) and $1,175 (Model 8L left handed)
Availability December this year.

Lefties will be pleased to see that a left-handed model will be available.

UPDATE: David from Stag told me that it is a short-stroke piston that Stag Arms designed.

Posted by Steve on Oct 1st 2009 | Filed in rifles | Comments (24)

Adams Arms Piston Review

Murdoc has written a review of the Adam Arms retrofit piston system for the AR-15 for Guns and Hunting.

The new Adams Arms gas block quickly mounted with hex screws and a new bolt carrier key, a couple springs and a bushing were all that was needed before adding the sleeved drive rod. Supplied front handguards mounted normally, and I was left going back over the installation manual, convinced that I must have missed something. It was that easy. Though it took me more than half an hour due to the troublesome factory gas block, this is certainly a task that can be accomplished by a moderately capable gun owner.

It is a well written review and worth reading.

This 3D animation shows how the piston system works verses the AR-15’s normal method of operation, direct gas impingement.

Posted by Steve on Jun 12th 2009 | Filed in rifles | Comments (12)

S&W M&P15 PS and PSX (piston AR-15)

This year Smith & Wesson have launched the M&P15 PS and PSX piston operated AR-15 rifles.

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M&P15 PSX

The only difference between the PSX and PS is that the PSX features a Troy 7″ modular quad rail handguard.

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M&P15 PS model and Piston Operating System
Photo
Remigiusz Wilk (REMOV). Used with permission.


Specs:

Barrel Length: 16″
Barrel Twist: 1 in 9″
Overall Length: 35″ Extended/32″ Collapsed
Stock: Collapsible 6-position
Weight: 6.5 lbs.
Finish: Hard Coat Black Anodized

I do not know the MSRP on either model.

Posted by Steve on Jan 23rd 2009 | Filed in rifles | Comments (24)

Tip of the day: Don’t fire a waterlogged AR-15!

This video clip is from a marketing video made by H&K comparing the 10″ barreled HK 416 with the M4 when fired full of water, immediately after being submerged.

It is a pointless comparison. Obviously Stoner did not design the AR-15 platform to be fired waterlogged. If he had it would be piston driven. Still, it is interesting to see what happens.

H/T: MP.net

Posted by Steve on Nov 18th 2008 | Filed in rifles | Comments (14)

Colt’s new AR-15 firearms

Over the past few months Colt has been unveiling a variety of new AR-15 firearms. If a replacement for the M16 or M4 is chosen they want it to be a Colt. To ensure this designed a range of weapons that should cover all bases. David @ Defense Review has been relentlessly covering the new firearms.

Many of the improvements Colt have developed have been applied to all these guns, I won’t list them all, click the links to read the full details.

Colt Sub-Compact Weapon (SCW)

A 5.56mm 10.3″ barreled sub-carbine/PDW featuring the new Colt side-folding stock. It is able to use an upgraded gas impingement system or the Colt Piston System (CPS)

Ausa Colt Defense Scw 5 Large
Side Folding Stock. Photo by SMGLee.

Colt ACC-M (Advanced Colt Carbine-Monolithic)

This is basically an upgraded M4. It features many small improvements over the M4A1 and Colt’s new monolithic rail system. If it was adopted it I think it would probably be named the M4A2.

Colt Advanced Piston Carbine (APC)

David calls this the HK416 killer. It utilizes the Colt Articulating-Link Piston (ALP) system.

Colt Advanced Hybrid Carbine (AHC)

This carbine features a hybrid gas impingement and gas piston system. I am very interested to see how that works.

Colt Infantry Automatic Rifle (IAR)

I covered this a few weeks ago on the blog. It is a light machine gun and Colt’s entry into the Marine Infantry Automatic Rifle competition.

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Colt IAR. Photo by SMGLee

Posted by Steve on Nov 12th 2008 | Filed in machine guns, military, rifles | Comments (7)

Bushmaster A3M4 Gas Piston photos

Jennersen was kind enough to photograph his Bushmaster A3M4 Gas Piston system for me. He took some really good shots.

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Thanks Jennersen!

The rest of them are here.

Posted by Steve on Jun 12th 2008 | Filed in photos, rifles | Comments (0)

POF-USA P-308

The POF-USA P-308 is a interesting rifle. It is a gas piston operated rifle, based on the AR-10/AR-15 design and requires no lubrication.

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14.5″ version

They achieve this by plating the upper receiver with silicon nickel and chroming and heat treating the bolt and carrier.

M.R.R. Full Lenght(C)
Upper receiver

Here is a video of it in action

In spite of its name, it is chambered in 7.62X51mm, not .308 (yes, there is a difference).

More info at POF-USA and Defense Review.

Posted by Steve on Feb 21st 2008 | Filed in rifles, video | Comments (37)