Strength of slide return spring in a 1911

[mikemyers]

Before I ask my question, here's a little background.

I spoke to Brenda at Les Baer, and asked her what strength slide return springs I should use in my Premier II if instead of shooting store-bought 230gr FMJ ammo, I use either my 230gr FMJ reloads with a light powder charge, or 185gr bullets, also with a light charge.

She suggested in the first case, I remove the 18 pound spring that came with the gun, and put in a 15# spring, and in the second case, a 13# spring.


My question for the forum, is how to know what spring to use? Bullet weight may vary, as well as the amount of powder for custom loads. Is there a chart posted somewhere, that gives some guidance as to what might be best?

• If the spring is too stiff, the slide may not cycle properly.
• If it is too soft, the slide may eventually damage something from slamming too hard as it is stopped.
• If the bullets are lighter, they will move faster, and have less of a force against the slide/spring.
• If the powder is lighter, again there will be less force.

Are there any guides indicating what to do?

 

[Jim K]

Why not try your loads? If the gun doesn't cycle, then you can try lighter springs. But there is a point where you can reduce the return spring too much and the gun won't feed and return to battery.

Jim

 

[MEHavey]

Go here:
https://www.gunsprings.com/Semi-Auto Pistols/COLT/1911 GOV'T PISTOL/cID1/mID1/dID1#799

Get the 13112 Stock No. 13112 - Reduced Power Pak - Conventional

You'll not know ahead of time (exactly) what will work with what particular
reduced load w/ your gun.

So start with a higher# spring and work down until the gun functions reliably.
Stick with that spring for that load. (Write it down)

I run 3-4 different springs from hardball on down.
EX: 200gr H&G68 using:
- Bullseye/4.0gr w/ a 12# spring
- Bullseye/3.6gr w/ a 10# spring

 

[WC145]

Trial and error. You're looking for reliable cycling and it should be throwing your empties about 6 feet +/- a couple.

 

[Jim Watson]

The other approach to selecting a recoil spring is to shoot rapid fire with each and see which one lets the sights settle back on target the quickest. Commonly done by USPSA shooters.

 

[imashooter]

All good advice. Just gather up a bunch of ammunition, a few springs and start the trial. Then when it's where you want it, get a few different hammer springs and a couple of flat bottom firing pin stops and turn it into your dream shooter.

 

[Jim K]

I still think the OP should try the loads he has before buying a whole bunch of springs he might not need or want.

Jim

 

[tipoc]

Jim K is correct.

Factory standard recoil spring weight for a 5" Government Model pistol is 16 pds.

Bear may be using a heavier weight because of the extra tight slide to frame fit on their guns (that tight fit will effect the reliability of the gun for a number of rounds as it breaks in).

At any rate, get the gun.

Get the bullets you want at the weight you want and shoot it. Shoot it a lot.

The gun will work well (or it should work well) over a wide variety of bullets weights with the standard recoil weight spring.

If you decide to use the gun as a dedicated gun for particular bullet weights than a change in spring weight may be in order. But if your just going to run a couple hundred rounds of 185 gr. through it, no change is needed.

https://www.gunsprings.com/Semi-Auto Pistols/COLT/1911 GOV'T PISTOL/cID1/mID1/dID1#3

I'll be blunt. You came here to ask about changing the recoil spring weights on a new Les Baer and had to call them to ask what recoil spring weight they are using. That tells me you have not done enough shooting at a high competitive level to know when and why to change spring weights and how that might help or hurt. Which tells me more shooting with the Baer to learn the gun and ammo. Do that and read more.

Visit here...https://forums.1911forum.com/forumdisplay.php?f=34

tipoc

 

[MEHavey]

...think the OP should try the loads he has before buying
a whole bunch of springs he might not need or want.

$2,000 gun....
a $31 springset isn't going to break the bank.

 

[tipoc]

a $31 springset isn't going to break the bank.

It ain't the money (clearly). It's the shortest way to knowledge vs. the long route. It's learning what the gun can do in it's time vs. swapping out various springs as you guess your way through things.

tipoc

 

[mikemyers]

........I'll be blunt. You came here to ask about changing the recoil spring weights on a new Les Baer and had to call them to ask what recoil spring weight they are using. That tells me you have not done enough shooting at a high competitive level to know when and why to change spring weights and how that might help or hurt. Which tells me more shooting with the Baer to learn the gun and ammo. Do that and read more........

Absolutely 100% true. ...and I haven't done ANY shooting at a high competitive level. None. I'm just trying to learn more, and another person at the club I belong to suggested that for shooting targets, 185gr bullets and a light spring would be a good idea. Calling Les Baer got me the information I wanted. The reason for this post is I wanted to learn a lot more about this, especially after someone asked me this very question last night, and I was unable to answer it.

In my opinion, trial and error is great, but it's good to learn as much as you can about something before you start changing things you don't really understand.

 

[mikemyers]

$2,000 gun.... ....a $31 springset isn't going to break the bank.......

The cost of the springs is irrelevant. After Brenda gave me the information, I ordered both springs she suggested.


From my original post:

My question for the forum, is how to know what spring to use? Bullet weight may vary, as well as the amount of powder for custom loads. Is there a chart posted somewhere, that gives some guidance as to what might be best?
If the spring is too stiff, the slide may not cycle properly.
If it is too soft, the slide may eventually damage something from slamming too hard as it is stopped.
If the bullets are lighter, they will move faster, and have less of a force against the slide/spring.
If the powder is lighter, again there will be less force.

Are there any guides indicating what to do?​

Seems like someone would have written an article about how to optimize the spring for different conditions. I'm not asking "what to do", but rather for more information so I understand this better.

 

[MEHavey]

It's learning what the gun can do in it's time vs. swapping
out various springs as you guess your way through things.

You don't guess. You do what Post #3 suggests.

So start with a higher# spring and work down until the gun functions reliably.
Stick with that spring for that load. (Write it down)

I run 3-4 different springs from hardball on down.
EX: 200gr H&G68 using:
- Bullseye/4.0gr w/ a 12# spring
- Bullseye/3.6gr w/ a 10# spring

That's not guessing.
That's engineering.

 

[tipoc]

Mike,

Go here...

http://www.bullseyepistol.com/


http://www.bullseyepistol.com/equipmnt.htm

http://www.bullseyepistol.com/cstomgun.htm


tipoc

 

[Chuck R.]

Is Baer still using the 18lb Variable spring?

That's what I'm running in my Baer Concept V for a little over 30,000 rds of 200 grn SWCs without an issue. I also used 16 and 15lb springs, both weights worked. I just got tired of swapping springs when I'd go back to shooting the 230s, so left the 18lb variable in.

Chuck

 

[imashooter]

I think the OP made good points and demonstrated he has a curiosity and desire to learn the dynamics of the firearm and how it's influenced by different loads / types of ammunition, and any other conditions/influences. Get a bunch of assorted ammunition, springs, etc and go have some fun. Charting and copious note taking will soon have that firearm dialed in to your shooting style and personality. I figure when the smoke clears you'll have a preferred defensive set of parameters and a preferred set for "other" if that is your goal.. You can go crazy analyzing ballistics and "shooting" data. It'd be cool to see periodic findings, opinions, etc of any studies you conduct if you choose to do that.

 

[nettlle]

It's not an exact science. Your spring, not matter what weight, will become weaker with use. I think if the spring becomes too weak the gun will start failing to return to battery. If too strong the gun won't cycle.

I don't think you can hurt anything experimenting with spring weights within reason. It's nice to be able to do it for smaller bullets and/or reduced powder charges. I do have an alloy framed 1911. I stay with the standard spring weight on it.

 

[1911Tuner]

As long as the slide makes full travel rearward, then strips a round, chambers it, goes to full battery and stays there, the spring's "weight" isn't all that important. The spring's job is returning the slide. Whatever else it does is incidental.

My litmus test for feeding and returning to battery is to assemble the gun without the spring and feed a full magazine by pushing the rear of the slide with the tip of one finger...briskly, but nowhere near full speed.

Browning's original spring wasn't rated in "pounds" and it wasn't 16 pounds in any event. By today's rating, it was closer to 14 at full compression, and around 13.5 pounds installed in the gun at full slide travel.

Until the 80s, about the only springs available were original spec. I've had my hands in multiple dozens of old 1911 pistols...the soft ones...the ones that were fired with the 14 pound springs. Many of them were well-worn and the most damage to the frame impact abutments I've ever seen was light flanging that cleaned up with a scrape in about 2 minutes. The guns were reassembled, and there was no compromise in function.

Neither do the small cracks that appear at the junction of the rails and the dust cover cause any functional problems. They're self-limiting, even without check-drilling.

There can be an issue with the impact abutment and spring tunnel in the slide, but the only modern slide that I've seen fail there turned out to be too hard and brittle when tested by Rockwell C scale. All the others have been pre-1946 slides, made before they started heat treating them...and they were ready for the scrap barrel anyway due to lug deformation.

The plain truth is that the slide doesn't hit the frame all that hard. The 1911...or any locked breech pistol for that matter...can be fired without a spring and without ill-effect.

 

[mikemyers]

I think it's my fault for the confusion in this thread. I was not asking "what to do", but rather a good explanation so I could understand it better.

"imashooter" understood perfectly: "I think the OP made good points and demonstrated he has a curiosity and desire to learn the dynamics of the firearm and how it's influenced by different loads / types of ammunition, and any other conditions/influences."

That is exactly what I want to know.

"1911tuner" added some of that information I was trying to find out.

I have two thoughts - I suspect that a whole lot of people know "what to do", but don't understand "why", and that everyone is trying to be helpful, by suggesting what I ought to do, but that's not what I was trying to find out.



Next time I post, I think I won't even mention what gun I have. I think I'll just write "how do bullet weight and powder charge affect the recommended slide spring weight?" That's sort of what I wrote, but I my post wasn't clear.

 

[MEHavey]

I'm sorry, but you [the OP] are going to know absolutely nothing until you do an actual field trial
with the load that you are contemplating. If that trial load works the slide w/ the spring you have
in the gun, well and good. If not, you are as in the dark as if you had not tried as at all.

ONLY by working your way down a series of springs in your gun, with your load you intend (or
eventually find you want) to use, are you going to find the knee of the curve for both gun & load.

Let's get down to brass tacks: Depending on where you are, you're likely paying $140-150 tax
on that pistol. Add a $30 spring kit and find all your answers.
.

 

[mikemyers]

Hmm, isn't that like saying it's worthless to read all the books about how a 1911 functions, unless I was about to take one apart myself?

I'm not trying to "do"; I'm trying to "understand". "Doing" (for me) comes later.

You're not wrong in what you said, but it's an answer to a different question.
If you read the original post, while it's not worded very well, it does suggest what I'm trying to learn.

 

[mikemyers]

..........The plain truth is that the slide doesn't hit the frame all that hard. The 1911...or any locked breech pistol for that matter...can be fired without a spring and without ill-effect.

OK, I'm even more confusabobbled than before. I thought one function of the spring was to "cushion" the impact on the gun parts as the slide moves backwards. You are actually saying that one can leave the spring out, and fire the gun, and it's not going to start damaging the gun parts? ....or am I missing something?

 

[MEHavey]

It's all MV = mv (well, mostly)

M (mass of slide) is constant.
V of slide moving back is a function of both the mv of the bullet [i,e., the load] and continually varies
the resisting spring constant ("F" measured in lbs/in compressed)

An 18-lb spring resists w/ 18lbs for every inch it is compressed
A 10-lb spring is nearly down to half that.
In the end, that spring's increasing force is what reduces the acceleration [A] of the slide to the rear to zero --
as well as where that zero point occurs. (hopefully behind the next bullet in the magazine)

Now the slide's MA = F = ma of the bullet at the start, and then the spring's F takes over and decelerates
the slide to a stop.

Now others have said here that NO spring is required other than needed to return the slide to battery, and
that repeatedly slamming the slide to it's stops under full recoil will do no harm. I reserve judgement there.

What I want is that heavy slide under smooth control to gradually come to a stop behind the next bullet in the
magazine, and then return forward to seat it in the chamber, ...again as smoothly as practical.

All this is theory however, and but a nice starting point to actual experiment in the real world w/ the specific
gun and the specific load in question.
.

 

[1911Tuner]

https://www.youtube.com/watch?v=Xyis5h9MvUU

The ammunition was Sellier & Bellot ball, provided by the camera man and delivered the day that he took the video. I didn't chronograph this particular lot, but others from that manufacturer have clocked in the 830-840 fps range.

If anyone wants to duplicate this, you need a FLGR system. The standard GI type guide rod will tilt and tie up the gun. You also need to verify that the bushing is aligned and centered between shots.

Aside from that...have at it.

 

[1911Tuner]

It's all MV = mv (well, mostly)

Muzzle velocity has little to do with it. The bullet attains about 90% of its terminal velocity within the first half inch or less of its travel in the barrel. It's more about the rate of acceleration and the force requirement to achieve that rate, and once the bullet has left the barrel...which occurs at nominally 1/10th inch of slide travel rearward...all acceleration of the system stops.

At that point, the slide can only decelerate...and after it's cocked the hammer and compressed the return spring...it just doesn't have a lot of force left as you can see from the video.

All this concern over the frame when it's the slide and upper barrel lugs that catch hell, and the spring can't do a thing about the recoil stresses on the lugs and the breechface...and the frame's impact abutment absorbs the load in compression...not in shear.

In all my years, I've never seen a frame impact abutment damaged to the point of being unserviceable. I've seen the cracks at the junction of frame rails and dust cover, but I've never seen a dust cover crack all the way through and fall off...not even on cast or aluminum alloy frames.