[JoeInKS]

i know that I am missing the most obvious reason, but, why can't the metal slide be made with a synthetic material as opposed to the metal which is used currently? Where did this come from? Buddies and I on a friend's land shooting away and someone brings up the Die Hard movie where the Glock was referred to as porcelain.... and away we went....

I thought the main reasons were:

cost - probably cheaper to make out of metal
durability / wear - sliding motion probably takes its toll as well as the sliding of the barrel at the end of the slide
needed weight - to control effects of bullet blast

What am I missing?

 

[Glockin26]

Steel can maintain tolerances required for smooth operations for many many rounds. Plastic will wear.

 

[ricklee4570]

Highly stressed areas still need to be made of steel.

 

[ede]

even if you could work out the stress and wear aspects you still need the mass of metal or a unreal strong recoil spring.

 

[american lockpicker]

Doesn't the FN 5.7 use a polymer slide?

 

[vmann]

Doesn't the FN 5.7 use a polymer slide?

no....

 

[mymini40]

A light slide would be hell in recoil even with the 9s.

 

[JoeInKS]

A light slide would be hell in recoil even with the 9s.

OK great so I was on target with my thoughts. Good point with respect to the tolerances needed. I was thinking that metal bushings or smaller set metal parts within the polymer would take care of the wear points but it always came back to the issue of recoil.

Thanks guys!

 

[bel970]

polymer does not react well to heat, even well below it's forming threshold the heat can cause the material to deform slightly with the expansion and contraction (back to holding tolerance) not to mention that in an integral part of the lock up just the ambient temperature changes would be enough to compromise accuracy, and good forbid you have a KB, little tougher to control the direction of the blast with a weaker material, not to mention how beat up it would get, carry a gun every day for a few years and the grip shows it. you'd run in to problems mounting the sights, keeping edges on the slide serrations (although stippling would work in their place).

once you overcome the engineering problems (and it can be done) your biggest problem is finding a market that will purchase it. look how long it took for polymer frame handguns to be accepted, even the nylon 66 never really took off and they did a lot to hide that it was a poly receiver.

 

[garyjandfamily]

once you overcome the engineering problems (and it can be done) your biggest problem is finding a market that will purchase it. look how long it took for polymer frame handguns to be accepted, even the nylon 66 never really took off and they did a lot to hide that it was a poly receiver.

Don't you also think that the mass of the metal slide coming forward also helps reliability; i.e. it helps bring the pistol into battery even with tight rounds or a dirty chamber? Just a thought...

 

[bel970]

yes it does, but in order to not beat the hell out of the gun, control slide speed and recoil and to get it to function at all the recoil spring would be tuned to the slide weight, I suspect at a minimum a dual spring system would be needed, something a bit more complicated could be needed though. you'd lose weight with a composite slide be it polymer or something more like carbon or carbon fiber but it would still require a fair amount of reinforcing metal alloy in high stress, high wear and areas involved in the lock up. although the weight loss would significant I think it would likely be less drastic than some people would think. cost alone would likely inhibit manufactures from using anything to exotic and material suitability would stop them from using less expensive alloys, more than likely carbon or stainless steel would be used.

I'm half surprised that a bryco/jennings/raven type company hasn't tried it yet.

 

[JoeInKS]

polymer does not react well to heat, even well below it's forming threshold the heat can cause the material to deform slightly with the expansion and contraction (back to holding tolerance) not to mention that in an integral part of the lock up just the ambient temperature changes would be enough to compromise accuracy, and good forbid you have a KB, little tougher to control the direction of the blast with a weaker material, not to mention how beat up it would get, carry a gun every day for a few years and the grip shows it. you'd run in to problems mounting the sights, keeping edges on the slide serrations (although stippling would work in their place).

Interesting. I did not think heat would be of issue considering that the grip portion and the area under the barrel was essentially subject to the same heat. Well thought out sir.... thanks

 

[bel970]

i work with plastics (forming and machining) and firearms, even polymer firearms but separately. mostly abs, kydex, acrylic and polycarb, it's been a long time since I've formed anything nylon based (which is what most polymer frames are) so I'm familiar with what happens. with the frame the rails are steel thermal inserts (glock/hk), steel chassis (sig/s&w m&p), or solid steel integrated with locking block (xd, with poly rear). really the frame isn't subjected to that much heat, it goes up and really the high wear area happens to be the same area that is involved with lock up/accuracy is only the front rails which are typically below the chamber and not the barrel wear most of the heat is (thinner walls, friction and most of the gas is in the barrel).

 

[Ol Timer]

I would think the breechface would blow back driving the striker through your skull.

 

[voyager4520]

The FN 5.7 pistol uses a metal slide that has a polymer cover for weather/corrosion resistance. I also wondered about this the first time I saw the 5.7 pistol.

Speaking to the issue of slide mass alone, without a metal slide the cycling would be entirely dependant upon the recoil spring. Some saturday night special pistols at least partially trend toward this concept and it doesn't work too well.