Firing the 1911 without a recoil spring, nothing broke

Firing the 1911 without a recoil spring, nothing broke

The long-awaited demo, brought to you by our own Hunter Lee Elliott.

First, a little background on the pistol.

The slide and frame are castings from Essex Arms…the supplier of castings for Thompson Auto Ordnance, and…to my understanding…formerly for Dan Wesson.

The set was a gift to me some years ago, and I threw a pistol together from various new and used parts that I had layin’ around. The problem was that the frame is made to GM-size specs, and the slide to Commander…which resulted in less slide travel than a Colt Commander has. Rather than drive the 70 miles to access a mill so I could cut the frame impact abutment and rails a tenth inch further back…I opted to thin the guide rod flange to .050 inch and regain half of the lost travel.

I may do the machining one day if I can ever find one of those increasingly rare Round Tuits.

I used a FLGR because I had one and didn’t see a reason to pony up the bucks for a Commander guide rod and plug.

Ammunition used was Sellier & Bellot 230 ball.

Language alert. I said a bad word.

I was careful to keep my finger below the muzzle and my finger off the trigger…even though the angle made it look like I didn’t.

The damage to the frame was there when I got it. I was the 3rd owner. How it came to be there is still a mystery.

The guide rod is necessary to keep the slide from being wedged into the frame rails. The flange is sandwiched between the slide and frame abutments to provide a flat impact surface for both.

The barrel doesn’t impact the frame bed. It stops on the vertical impact surface in the frame at or just after the link has taken the barrel as far down as it can. Ideally, there should be about another .003 inch for the barrel to drop to the bed…and that’s under gravity.

To date, the pistol has seen about 5-6 thousand rounds. The recoil spring was originally a 14-pound Wolff spring intended for a 5-inch pistol. I cut it down to 24.5 coils for the Commander. It hasn’t been changed since it went into the gun.

The no-spring thing: What really delays Johnny’s slide?

First, a quick description of the locked breech/short recoil operation.

Bang. Force forward drives the bullet while force backward drives the slide. The slide grabs the barrel by the upper lugs and hauls it back with it. At nominally 1/10th inch of rearward slide/barrel travel, the bullet exits, and all accelerating force is gone, and all movement…slide and bullet…is due to momentum conserved while the bullet was making the trip.

Newton’s 3rd Law in action…but we have to consider Newton’s 1st law and factor it into the equation. Newton 1B states that an object in a constant state of motion will remain in a constant state of motion…UNTIL an outside force causes it to change…meaning causes it to slow down or stop moving.

Outside forces are easy to identify. The slide’s mass. The recoil spring. Hammer mass and mainspring. Slide to frame and slide to hammer friction, etc…but sometimes the outside force comes from inside the system. Those are a little more tricky to see and understand.

The largest force resisting and delaying the slide…slowing it down…is the bullet itself.

When we think of action and reaction, we usually think of it in terms of forcing an object to move or to keep moving against outside forces working to bring it to a halt. i.e. when we push on an object, we GET pushed away from the object by the vectored force that exists between us and the object. It also works in reverse. When we PULL on an object, we get pulled toward the object.

There is a high frictional force that exists between the bullet and the barrel which resists the bullet’s movement forward. It was measured once by a colleague of mine. Pushing a jacketed 230 grain bullet through a barrel required 103 pounds of force to enter the rifling and a continuous 93 pounds to keep it moving.

Now to the tricky part.

Since force forward = force backward…the resistance that the barrel imposes on the bullet, the bullet imposes on the barrel…in equal measure. Because the barrel is being forced to move backward at the same time that the bullet is moving forward…whatever force resists the barrel’s movement backward affects the slide’s movement backward.

Now for the story that goes along with all this.

Back in 2007, I had a houseguest who made the trip from Monroe, Louisiana to attend an engraving course in an adjacent county. A pistolsmith and knife maker, we’d discussed this principle at length on pistolsmith.com…and he couldn’t quite wrap his head around it…until I did a simple demonstration with a broomstick. The light went on.

The guy had apprenticed under renowned pistolsmith Jim Clark, and he’d remained friends with his son Jim Clark Jr…a fine pistolsmith in his own right…and when he went back home, he visited with him and brought these points up, adding the broomstick demonstration.

Jim Jr. was working on a gun, and listened…then was quiet for a minute. He laid his file down…looked at Bill…blinked and said: (verbatim)

“I’ll be damned! That’s how it works! I never thought about that…but that’s exactly how it works! I’ll be damned!”

Over the years…whenever I’ve explained this…some people have seen it immediately. Others have to chew on it for a while. A few never get it until they see the broomstick demonstration…or do it themselves. A small percentage don’t get it even with the broomstick. Once, during a workshop that i hosted, i had the privilege of having a sharp young lad in possession of a new engineering degree. While I talked, he listened…grinned and nodded…and said that it was spot on. His words were; “Yep. Exactly. It has to work that way.”

And that’s why the 1911 and any locked breech pistol can be fired successfully without a “recoil” spring.

The spring does add resistence, but as the video shows…the slide just doesn’t hit the frame all that hard…with or without a spring. For what it’s worth, I’ve done this demonstration with a Colt LW Commaander several times over the years, with roughly 500 rounds of hardball. The frame abutment is fine.

Heavy springs…

Springs work in both directions. A too-heavy recoil spring doesn’t give the magazine as much time to get the next round into feeding position and stabilize it, which can cause Bolt Over Base misfeeds. Then, there’s the issue of bringing the slide to a stop…which is done by the barrel’s lower lug feet impacting the slidestop crosspin. I’ve seen those feet crack and even shear off.
The impact abutment is designed to take the hit. Those tiny lug feet…not so much.

And…the heavier the recoil spring, the sharper the felt recoil. When the slide starts to move and compress the spring, it the spring becomes a force vector in an action-reaction system separate and apart from the one that started with the powder ignition. It pushes forward against the slide and backward against the frame. The heavier the spring, the harder it pushes.

 

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