Slide Weight

I’m still a neophyte but have built two. 2011 & 1911.
I wanted to broach this subject of slide lightning. It’s probably true that removing material from the slide can reach a point of diminishing returns.

Using recoil spring weight and a lightened slide would need to find a happy medium. There are so many ways to remove weight in an attempt to speed up the cycling that it’s not really the subject.

I’ve seen a guy weight his slide during the process of milling off weight in increments while milling material off.

So let’s say that I’m am building a slide. Competition shooting major. Giving it parameters, .45 ACP, shooting it with reloaded ammo an average power factor of 170. Enough above 165 to be safely in the game.

Is there a way to calculate slide weight? Or am I mistaken and it is just a marginal way to lighten but really about aesthetics?


I finally found some data on slide lightening and the purpose for competition pistols.
Am in Georgia visiting my daughter and her husband and the new grand baby. So I’ve been reading off and on.

Lightning the slide does make it operate faster however it’s not haphazardly done. The idea being to get it to operate level. Which in all cases would be the recoil spring weight selection. Taking 70% of the weight off the front and 30% off the back is a good starting point. Then selecting the right recoil spring that eliminates muzzle drop so that follow up shots are quicker when the slide hits the end of the travel.

It is the exact opposite of what I would have thought. A heavier spring actually makes the pistol susceptible to malfunction as it returns too quickly and fails to strip correctly or even fails to strip the next round at all.

By changing the slide weight to lighter, it makes the slide faster with the lighter spring and yet still allows enough delay in the open position to allow the mag to elevate the next round.

The entire process is about speeding up the slide and returning the pistol to a level position without muzzle drop. I now understand. It’s quite possible that I might ruin a slide or two learning exactly how to even it all out.

If anyone has more information, trust me, I’m all ears. Do I understand all this correctly?


Yes the lighter the slide the lighter the spring rate. Till you get to the point the spring won’t strip the next round and chamber.
You also can take off weight on the slide by rounding corners and makeing the slide more snag free.


Perfect. Succinct.


You really don’t, though…


I will when I do it. Understanding comes after application. If someone else learned it then it isn’t esoteric. If I can design a full gas plant or refinery from scratch, I can learn this. Thanks for the boost.


Have you read anything from Jerry Kuhnhausen?


I don’t believe so 6un5. If you recommend it, I will read him. At this point my only goal was to understand the mechanics and the physical dynamics. Nobody posted to the thread so that generally means there’s some complexity to running out the mechanics or there are some proprietary ideas concerning each builder’s methodology and ideas.

There was some false data that I was carrying around that most people have in common. “A heavier load requires a heavier spring.” The answer is complex and I may not have the words to express it now. It’s a weak yes. But it’s partially true but also a resounding no. The more straight answer would take the slide weight, which would be a more important consideration and not how powerful the load is but it could also be applicable in the right context.

Do you recommend reading him? Please direct me to him.

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Some people consider Jerry Kuhnhausen’s books on the 1911 (a two book set) a good starting point for understanding John Moses Browning’s design.


Also, if you don’t already have a copy…


Thank you. Already ordered the two volume set. Plus using other references. I have the drawings and tolerances for the 2011 STI at home. Have them printed off. As well as the different rear sights dimension dimension cuts.

Putting a Bomar on the 2011 I’m in the middle of.


6un5, do you know if the solidworks model is available? I can animate it at work if I get some time.


There are some floating around, but I don’t have anything saved to my hard drive.


My copies just came in. Finally some good reading material. I will most likely have questions.