Plastic/synthetic gun components

[Slater]

Gun makers are substituting plastic for metal in various gun applications these days, such as guide rods and trigger housings. A lot of people don't like them and swap out the plastic for metal (if available). Has anyone ever experienced (or heard of) a plastic part failing prematurely?

I was wondering if the plastic would theoretically last as long as the corresponding metal part, or wear out/break much sooner.

 

[Tag]

the stock guide rod in a Glock is plastic, and they have been known to last for hundreds of thousands of rounds.

Kimber uses plastic in the mainspring housing, which is probably just as well.

As far as 870 trigger guards and whatnot, I would like to see metal, but I've found modern polymers to be awfully tough.

 

[Deavis]

A lot of people don't like them and swap out the plastic for metal

That is called irrational prejudice. The reason people swap them out is because it doesn't fit their preconceived notion of how a firearm should be made. People thought Glocks were crap when they came out because they were plastic. Everyone *knows* a gun is made of a heavy steel frame and covered in wood, like a 1911.

If a plastic part is properly engineered it will give service equal to and exceeding a corresponding metal part. Properly engineered plastics will never rust, corrode, or experience metal fatigue. When plastic parts are failing prematurely it is not necessarily an indication of a material deficiency but most often an engineering mistake, IMO

 

[WhoKnowsWho]

The reason people swap them out is because it doesn't fit their preconceived notion of how a firearm should be made.

Just like the Beretta Storm's plastic hammer, some people will not buy it simply because of that. Hasn't failed yet, won't be surprised if it doesn't in my lifetime.

 

[nico]

I completely agree with Deavis. Although manufacturers are partly to blame for not educating consumers. When people hear that something is made out of plastic they think of the disposable plastics that are used in soda bottles. They don't realize just how far plastics have come in the last decade or two. With a little education, people would realize that thinking of a soda bottle when you hear "plastic" is no more accurate than thinking of tin cans when you hear "metal."

 

[JohnKSa]

I have no problem with guns that are engineered to have plastic parts. I have a VERY hard time with a gun company simply swapping out a metal part for a plastic replacement to save some manufacturing $$$.

 

[Slater]

I think that plastics probably have a few advantages over metal, such as corrosion resistance and a certain amount of "give" when impacted.

I was doing some reading about the Mossberg 590 shotgun, and came across the Milspecs for pump shotguns. MIL-S-3443E (20 March 1989) had this to say about the trigger guard:

"The trigger guard shall be of metal or suitable glass-filled nylon plastic construction and shall have sufficient strength to prevent manual deflection of the bow (causing actuation of the trigger mechanism) or permanent deformation of the bow. The bow of the trigger guard shall withstand a static load of 220 pounds applied at the outside surface of the trigger guard bow, perpendicular to the trigger guard and on the vertical center plane of the shotgun."


The latest (and apparently last) revision of this document was MIL-S-3443G, dated 4 Oct 1993. The same paragraph reads:

" The trigger guard shall be of metal construction and shall..."


Evidently the synthetic trigger guard was deficient in some respect. Anyone have any particulars?