A gentleman who has been making parts for lighthouses (just about anything including lenses) for a very long time asked me if I thought people would buy 80% 1911 frames made of brass, bronze, or similar metals. I really don't know much about whether or not those materials would be appropriate for a 1911 frame, but it sounded like a neat idea, especially if he could bring them to market with some nice scrollwork on them ready to finish. So, is this a terrible idea or would it be worth the effort? He came in my shop a months or so ago and I saw his card lying there on the counter and figured I'd go ahead and get some consensus for him before I forget again Mods, if this is a problem please feel free to lock, delete, etc. I am not the guy wanting to do that, I am a shop, but 1911s are not my forte. He seemed like a true old school type craftsman and I want to help him get an idea of whether or not he should try it, that's all. The very limited market for lighthouse parts has him wanting to diversify.

They made cannons out of bronze so those could be nice looking. Plus they patina which would add character to it.

It would definitely be different. I think bronze would look good with scrollwork and a little accelerated wear and patina on it. I don't own any 1911s anymore, but I might be interested in one like this. It seems the longer I go without shooting Glocks much the better I get at shooting 1911s when I have to, so I am leaning toward owning another someday.

Brass frame revolvers were common during the Civil War (Griswold).

The reason semis don't have frames made from brass is that it's pretty damn brittle compared to modern steel and alloy.

I would be concerned about the strength . I have cracked an aluminum frame 1911

Bronze has been done before and it seems to have worked out ok.

I am familiar with the 1930s pistol you mention.  As I understand it, it successfully endured a 5000 round firing test.  (Not a lot by modern standards, but enough t show that the concept has some merit).

Years ago, there was some one offering bronze 80% 1911 frames.  I remember seeing pictures, but don't know if any were ever actually completed and fired.  The bronze components certainly looked attractive.

Bronze was used quite a bit in the 19th and early 20th century for gun parts.  It was much easier to cast than steel with the methods of that time.

I have no doubt that a bronze 1911 would function, but I would worry about it's service life.  Of course, cosmetics being the primary reason for its existence, this might not be a problem.

I don't know, there's now a polymer-framed 1911 and there have been aluminum framed ones for many years - why not bronze? With a high-polish blue slide and color-case/fire-blue parts and double-diamond walnut grips. I would sell guns to get it. Actually it would be easy to make one that looks the part simply by brass-plating a frame and doing faux color case on the hammer, slide stop and thumb safety and fire blue on the trigger, pins & screws, regular blue on the barrel, mag release, MSH, grip safety and barrel bushing.

I appreciate the great input and info. I'll see if there is an email address on that card and send him a link to this.

I'd be in for brass. While you're at it tell him to make brass AR lowers. I recall seeing an ad in shotgun news a few years ago for brass lowers, but it disappeared and nobody on here knew of any.

Perhaps some kind of alloy that would give the same kind of golden tinge to brass, but stronger than brass.  I'm no metallurgist, but perhaps such a thing exists.

You know, for MAKING 1911s.

Brass is actually stronger than people think it is. I have a welding book written by a guy who says he welded stuff for NASA and taght welding at a college. He wrote in the book about this lab testing machine that pulls on something to test strength and he demonstates a piece of brass versus steel and IIRC he said brass was actually stronger. It was relavent to welding because sometimes you braze with brass rod. People have built go kart frame with nothing but brass brazing rod holding it together.
I wunder if he was thinking about making (rough) castings or CNCed frames? Sarco used to sell rough castings, stainless I think, they were FAR from 80%. Required shit tons of work to finish them off.

There's no way brass is stronger than steel, but again I'm not a metallurgist so I could be wrong.  Higher ductility maybe, where brass stretches whereas steel might just fracture.

It would be easier to machine into a 1911 frame I would imagine, considering it is softer.

I would think you would need steel inserts for the slide rails or you will get excessive clearances in that are.

Yeah it would definitely need some pinned in steel rails or something of the sort. You might be able to plate them with something to hold off wear, but you still have the work hardening which would likely lead to cracking in short order...

Will be a little heavier, in an industry where people agonize over fractions of an ounce.

There is steel a steel insert in the frame for the slide to ride on.

Many of the polymer frame guns are made this way.
Especially in large calibers.

Also brass or bronze is often hammer-forged to increase strength. I don't think there's any commercial viability in it except as a very cool 'special'.

With a brass frame revolver stuff was mounted to it with screws . all the wearing friction parts like triggers , pawls and so forth were steel or iron
With a 1911 frame you have a whole lot of sliding going on . I can't imagine brass would hold up well . Bronze can be pretty tough , something less than steel in a regular 1911 frame but I expect it would be toughfer than a alloy LW commander /

Is there much of a market for 80% 1911 parts?

If the gentleman has the ability to cast and work bronze does that in any way translate into the ability to cast and work alloy? LW frames might have a larger market than bronze

There are a few things to consider mechanically if you want to know how materials compare.   Real world tests would be most "satisfying" but you can look at tabulated numbers.

AISI 4140 steel as used by STI inc to manufacture their slides and frames has a Tensile and Yield strength of 95,000psi and 60,200 psi respectively.
http://www.azom.com/article.aspx?ArticleID=6769

For comparison C86300 Bronze (a version of manganese bronze) has a Tensile and Yield strength of 110,000psi and 62,000psi respectively.
http://www.concast.com/c86300.php

One of the big practical differences I see is that the modulus of elasticity is 27 million psi vs 14.2 million psi for 4140 and C86300 bronze respectively.  Basically steel is almost twice as able to resist stress than the bronze.  The other big difference is that the steel is significantly easier to machine with a machinability of 65 vs 8 for bronze.

YMMV as my amateur analysis is probably as 'tarded as me!

Young's modulus is the one that matters.

Stealth arms already offers aluminum frames.

I would say that and its machinability rating which might be a good indicator at how it would wear over time.

As mentioned the modulus of elasticity gives the winner away, especially for a semi auto. The bronze you linked is not typical bronze either. It is one the strongest bronze alloys (high tensile), and it is expensive.
I program and setup CNC machines for a living so I looked up machining feed rates and tool life for that alloy and even this free machining version is just MEAN to tooling. I am not even sure what I am seeing is correct because it doesn't seem right. Most bronze and even manganese bronze alloys are 80 machinability or higher, some way higher. 8 is the same as INCONEL!!! A superalloy used in jet engines... it is generally investment cast. According to what I could find tooling will last a fifth as long compared to 4140 AND it takes longer to machine a feature because you have to step it down a lot. Screw that stuff haha. I can only imagine someone trying to finish an 80% receiver at home LOL. Hope I never have to cut it.


Data for C86200 is WAY better in terms of machining and the tool life is near infinite. That website gives it a MR of 30 which still seems low.
Machinabilty List

Also, those numbers you have for 4140 are at full anneal. Slides and frames are usually hardened into the Rockwell C scale (40+). That is 92 B scale. So those STI slides are likely even more strong and resistant.

I would really like to see a bronze framed 1911 and how it holds up. The M1911 is already old school, might as well bring it back to the bronze age and really have those 'space age polymer' guys scratching their heads haha. They would certainly have to be quality castings with no inclusions and such.

Do you happen to know how to factor in the heat treatment?  I'm curious how that would change the numbers for both the 86300 and 4140.

I am not sure exactly what you mean by factor in, but heat treatment would (assuming proper HT), make the 4140 stronger. It will not effect the modulus of elasticity, just tensile and yield strength.

MatWeb 4140 search

Here are some college kids' lab report. 4140 Lab Report
They used test pieces of 4140 in "received", annealed and hardened+tempered condition. Hardest of theirs was only 33 Rc. It had 180,500 psi yield, 191,000 psi tensile.
I was wrong too, that 4140 page you linked to is not full annealed. Likely work hardened or heat treated. Full annealed 4140 is around 80 Rb.

That bronze cannot be heat treated for hardness. Few copper alloys can be, and they are hardened using precipitation hardening like many aluminum alloys are.