Gun Hub Forums banner

1 - 11 of 11 Posts

·
Premium Member
Joined
·
1,277 Posts
Discussion Starter #1
Some of you may remember Natec by its previous name Amtech, back when they were trying to market a polymer-cased .38 Special round in the early '90s. (Unlike the '80s-era USAC, these used standard .357-358" projectiles.) At the time, Amtech reps handed out publicity kits containing the other polymer-cased cartridges with which they were experimenting. These included the 5.56x45mm, the 7.62x51mm, and even the 12.7x99mm (.50 BMG).

While they quickly left the commercial market, they have still been at work with US military funding. They have received a new boost with the JSSAP requirement for a "Lightweight Family of Weapons and Ammunition".

It seems like Natec is closer than ever to making a viable plastic-case 5.56x45mm. Earlier in the year, they had projected opening production of new polymer-cased cartridges by late summer.

At last check, they are located in Plattsburgh, NY.
 

·
Site Founder
Joined
·
4,081 Posts
I remember Amtech well. Between 1998 and 1999 Tom Burczynski was consulting for them and I was helping Tom with pressure testing/load developing for their .38 Special and .223 stuff. I still have some of the prototypes laying around somewhere.

Had some real hairy experiences with the .223 version. In one test the case tore open in a Colt AR-15 sending bolt parts out of the ejection port.

There were all kinds of problems with getting the bullet to stay within the cartridge case. Various techniques were being tested to both keep the bullet in place while allowing for the pressure to build within the case after the primer was ignited. The neck of the case was weak enough that if you applied moderate pressure to the bullet the neck would distort enough to release the bullet.
 

·
Premium Member
Joined
·
1,277 Posts
Discussion Starter #3
Fernando Coelho said:
Had some real hairy experiences with the .223 version. In one test the case tore open in a Colt AR-15 sending bolt parts out of the ejection port.
Yikes!

I know that there has been R&D with polymer-case 5.56x45mm since the '70s...Gulf + Western was one of the players then. I still suspect that it is more viable for military applications than pure caseless technology. Indeed, the same technology used for cast/pressed powder charges in the DM11 or the Voere UCC could probably come in handy in eliminating some of the handling and storage issues with polymer cased cartridges.

With regard to the neck tension issue, were they injection molding the case body around the bullet during your time of interaction? (This has been mentioned as an option.) As mentioned above, an en-bloc propellant charge ought to prevent bullet setback, but inadequate bullet pull poses its own problems.
 

·
Site Founder
Joined
·
4,081 Posts
There was also the time I fired an early prototype from a Contender and couldn't get the spent case out. In the end the chamber had to be reamed.

There were a few ideas in the works in an effort to solve the bullet problem. One was to roll the case mouth into a cannelure on the bullet. That didn’t work. Another idea was to apply a sealant to the neck. As you pointed out there was the concept of injection molding the case around the bullet. The most exotic idea was to ultrasonically bond the bullet to the case. The prototypes I tested had the bullet seated into the case mouth and held in place by neck tension only. At the time I was involved an adequate solution had not been found.

For the powder, there was a barrier molded into the case right where the shoulder of the case turned into the neck. To load the cases you poured the powder into the base of the case. You then snapped together the Zytel case body to the primed brass head cap. At that point the bullet would be slipped into the case mouth. At least that is how it was with the prototypes.

The weakest point of the design was the junction point between the brass and the Zytel. That was more of a problem than the case mouth weakness. Even if these previous problems were somehow solved, I still can't see this type of ammunition holding up to field conditions.
 

·
Premium Member
Joined
·
1,277 Posts
Discussion Starter #5
An Alternate Idea

Well, if the joint between the polymer body and the metal casehead is too difficult to maintain, how about eliminating the polymer body altogether? With solid propellant charges, one could conceivably create a semi-caseless round. The trick would be to use a casehead just large enough to provide obturation in a conventional rifle action. Conceivably, you could even retain the use of conventional primers.
 

·
Site Founder
Joined
·
4,081 Posts
At the time they were still working on how the case would connect with the casehead. The problem I was seeing was if the polymer case stuck to the inside of the chamber for any reason, the bolt/bolt carrier was still going to forcibly attempt to extract the case by the casehead. That tug of war was a problem I don’t think they can overcome.

If they eliminate the polymer body all together and attempt to use some form of solid charge, they would still have to connect the primed casehead, charge and bullet. Add to that field conditions like our soldiers are seeing in Iraq and Afghanistan and I see a serious durability problem.

The advantage the Amtech concept has over conventional ammo is less weight. That was the driving force behind all the financial assistance Amtech was receiving from the government. If each foot soldier could carry more ammo for the same weight they carry now, the military wanted it. I think all that money would have been better spent on bullet design or even exploring alternative calibers.

With regards to the patent, I can’t recall. When I went with Tom B. to their facility when it was down at Stennis we had gone over a tremendous amount of background on the project. Looking at the way the whole operation was running, how they were spending their money, and who they hired to do the selling for them, it was looking like a dead end project even back then. My interest in the project was having Amtech make bullets for Triton. They were supposedly going to set up production lines to make handgun and rifle caliber bullets in-house and their salesman was pushing for Amtech to supply us with our Hi-Vel and Quik-Shok bullets. In turn we would allow Amtech to utilize Quik-Shok bullets for their ammo.
 

·
Premium Member
Joined
·
1,277 Posts
Discussion Starter #8
FWIW: Natec now has their poly-case .223 Remington ammo out in the commercial market. It even comes in different case colors for the fashion conscious. (Coyote Brown/Tan is the new Black.) Reportedly, they will have poly-case .308 Winchester ready by June.
 

·
Registered
Joined
·
178 Posts
..

Daniel, can you post a link to either the company's site that has info on this plastic cased round, and/or to a company, site, or store that is carrying it? You did say that it has hit the commercial market?
 

·
Premium Member
Joined
·
1,277 Posts
Discussion Starter #10
1 - 11 of 11 Posts
Top