Recoil & Mainspring rates for Duty Pistols:

[10851Man]

Greetings,

I carried a stock 1917 production Colt 1911 as my primary on-duty pistol for nearly 9 years. I have found that a completely stock WWI 1911 (circa 1917) is 100% reliable (over 8,000+ rounds) when kept in stock condition (all springs, adjustments, etc.) and fed exclusively Federal 230 grain Hydra Shok through ‘Mil-Spec’ Government surplus (new) 7 round magazines, or original ‘Colt’ 7 round magazines.

We currently authorize only the ‘Mil-Spec’ magazines (with government contract/assembly numbers), Genuine ‘Colt’ 7 and 8 round magazines and Wilson Combat 7 and 8 round ‘FBI HRT’ specification magazines. I have not found it necessary to ramp or throat this pistol when maintained within these guidelines.


Although many 1911-style pistols are extensively ramped and throated, I have found the ogive of the current configuration of the Federal 230 grain so closely mimics the 230 grain military ball projectile that it feeds just as well in the old pistols. I hold all the 1911’s that I work on to ordnance specification. I do make hammer and sear pins to fit the frame precisely in some guns with out of tolerance holes, but only to restore correct pin to hammer/sear/frame interface.

There is an increasing trend towards using a 19.5 lb main spring and 18.5 lb recoil spring, in place of the stock 23 lb main spring and 16 lb recoil spring. The theory is lower reward slide velocity. However, I have long thought that this would increase slide velocity into battery and perhaps create some feeding issues. I am also aware that the radius of the firing pin stop can affect this velocity as well, although I favor the 'Post A1' style radius.

Since everyone seems to rate their springs differently, I wanted to open up some discussion and get some ideas on a good spring rate for 5" duty pistols shooting Federal 230 grain ammunition.


Thank you for your time an attention regarding this matter.

[Baldy]

I see no reason to change what is working in my pistol, which is a 16# recoil spring and a 23# main spring. I am going on 3,000rds trouble free. I would not hesitate to carry it if I was a LEO.

[10851Man]

Baldy,

I tend to agree with you. I wanted to post this in hopes of getting 1911Tuner to chime in with some input. Although it wasn't covered in the 1911 Armorer's Course, I would assume that mainspring rate and firing pin stop radii may affect unlock timing to some extent.

The 19.5 lb main spring and 18.5 pound recoil spring seem to closely relate to the 23.0 lb x 16.0 lb stock spring rates, so I was curious to hear what 1911Tuner (and others) have to say on the topic.

Thanks...Robert

[wichaka]

I went with the original specs on my duty 1911's.

That is a 14lb recoil spring, and small radius firing pin stop. Where the industry has come up with a 16lb spring, I have no idea. So if one goes to an 18lb spring, you've just over did the recoil system by 4lbs. And I use a 23lb main spring.

The setup I mention above , gives a very easy, smooth, and flat recoiling 1911...even with +P HP's.

I issue either the Federal HST, and until the stock runds out, the Rem. Golden Sabre. Both will run fine in a stock ramped/throated barrel.

Your Hydra-Shoks will be phased out in the next few years, in favor of the HST. So you may want to experiment with that round soon.

[10851Man]

Thanks for the input...

According to sources at Colt, the 16.0 lb recoil spring was employed along with the 'A1' modified firing pin stop radius.

We just got a shipment of the new .45 HST, but I haven't tested any of them yet. Additionally, I just received a couple of the new Wilson tactical Elite Magazines for testing...Robert

[John]

Stronger springs protect an area of the pistol which was designed to take the beating. Unfortunately, they increase the beating in areas which were NOT designed to be beaten by the added velocity a stronger spring produces when the slide returns to battery, namely the barrel feet, the slide stop and the slide stop holes.

Remember, springs work in both ways.

For my 5" pistols, I use exclusively a 16 lbs recoil and a 23 lbs main spring.

[10851Man]

John,

Your observations on slide velocity into battery mirror that of what Colt has told me for years. I wanted to post this question to the forum in hopes of obtaining views from those who shoot more than I do.

I had a 1911 Springfield recently that belonged to an officer from another agency. It had an occasional feeding issue (failure to go into battery) and the slide would not lock open everytime.

He sent it back to Springfiled and they polished the disconnector and the bottom lug of the slide and returned it to him, thinking this is what was keeping the gun from going into battery. However, the problem persisted.

What I discovered was he had installed one of Wilson's 'Custom Tune Spring Kits' which mates the 18.5 lb recoil spring with a 19.5 lb main spring. When I went back with to a 16 (or 17 pound) recoil spring and 23 lb main spring, the feed problems stopped.

I believe the increased slide velocity into battery effectively 'narrows' the window of time that the weapon has to feed itself. I have also found evidence that the 18.5 lb and 20.0 lb recoil springs increase the instances of 'pushfeeds' in these pistols.

Now the failure to lock open was next on my list and I noticed a lot of wear on the slidelock and the slide catch noth. I fired a few magazines through the pistol and ended up with a couple of failures to lock open on the last round, which sent the slide home on an empty chamber.

What I discovered was the recoil spring guide in the Springfield was about .060" thicker than any of the Colt variants I had in my parts tray. When adding the Shock Buff to this equation, the rearward travel of the slide is reduced and the slidelock ends up catching just the edge of the slide catch notch.

I threw the Shock Buffs away, dressed the notch in the slide, installed a new slidelock and the problem went away.

Now I am aware of people who like to use the 'pre-A1' style, low radius firing pin stop and 14 lb recoil spring, but I have never used them...Robert

[10851Man]

I was recently asked by one of our officers to endorse the Wilson Combat magazines for on and off duty carry. We had approved them for off-duty use, but had never approved them for on-duty use.

I discovered the wouldn't feed properly when fired upside down, based on an 'officer down' (lying on back, firing over the head weak handed) training scenario. I wrote to Bill Wilson and got some of their improved Tactical Elit magazines which are supposed to address this issue.

I am yet to test them...Robert

P.S. I personally use the 'Mil-Spec' magazines (with contact and assembly numbers) or 7 round 'COLT' magazines in all my 1911 pistols...

[John]

A few remarks:

1. I have used the EGW small-radius FPS in my old Colt for years, with 16 lbs recoil and 23 main springs. Sweet shooting, that's all I can say. Wichaka advocates 14 lbs spring, since this is the closest one to the original John Browning design specs. I have never tried it, but I do believe that the less the strength of the recoil spring the sweetest the pistol becomes. If a 5" 1911 doesn't work with a 14 lbs recoil spring and a 23 lbs main, then the problem is NOT the spring.

2. Wilson mags. I admit my experience with them is not great. Years ago, Bill Wilson was kind enough to send me two of his 47D mags for testing. They didn't work in my Colt. I gave them to a friend, who told me they work fine in his. Both pistols were Colt Series 80 pistols, mine blue, my friends stainless. Go figure.

3. I am not sure what you mean by mil-spec magazines. No one has made any mil-spec magazines since 1945, so I am not sure if there are some of them still around. Usually those you buy with mil-spec markings are not real. I had very good experience with Colt 7-round magazines of GI specs and of hybrid specs. With FMJ, I would be hard pressed to find a difference between the two, I would say the GI feed smoother than the hybrids, but the hybrids are better for JHP.

[10851Man]

John,

Quite a few years ago, I bought a lot of 125 'Mil Spec' magazines in packaging dated 1954. All are new and in perfect condition. All have assembly/contract numbers on them and all are identical in appearance to the Colt 7 round 'GI' magazines. These work very, very well and I continue to use them...Robert

[Tom]

I had a 1911 Springfield recently that belonged to an officer from another agency. It had an occasional feeding issue (failure to go into battery) and the slide would not lock open everytime.

He sent it back to Springfiled and they polished the disconnector and the bottom lug of the slide and returned it to him, thinking this is what was keeping the gun from going into battery. However, the problem persisted.

What I discovered was he had installed one of Wilson's 'Custom Tune Spring Kits' which mates the 18.5 lb recoil spring with a 19.5 lb main spring. When I went back with to a 16 (or 17 pound) recoil spring and 23 lb main spring, the feed problems stopped.
I assume the pistol no longer had Springfield's ILS mainspring housing and components?

[10851Man]

It was an older Springfield 1911A1 with a 'NM' serial number prefix...Robert

[log man]

It was an older Springfield 1911A1 with a 'NM' serial number prefix...Robert
The ILS has been around since at least 2001 and the NM prefix is used today and back some twenty years.
Terms of interest, slide stop, slide stop notch, disconnector rail.

LOG

[John]

1954 was about 55 years ago. Today, these magazines no longer exist. Not everything stamped with a mil-looking-like number are original magazines.

[10851Man]

Agreed, John...

I bought these along with a cache of government surplus .45 parts from a private collector. All were still in military packaging when I purchased them. I have used the same 5 magazines since 1992.

More recently, I have purchased the 7 round magazines made by Colt with good results for our agency...Robert

[kenhwind]

Well, we have 2 Colt Checkmate magazines, that I had purchased from Brownells. When my brother and I were at the range I saw one of these and I thought it was a Series 70 Pre-Hybrid feed lip magazine.
Nope, Checkmate; GI feed lips, and they work like a champ.
I have three GI mags that stay loaded and these work just fine too.

[10851Man]

Ken H. Wind,

I am not an expert, but I have learned a few things from experience and talking to those with more experience than me. Here are my thoughts on magazines in the 1911 pistol.

The 'Mil Spec' or 'GI' style magazines worked on Browning's principle of controlled feeding, which held onto the cartridge until rather late in the feeding cycle. The Wilson magazines tend to release the cartridge quite early in the feeding cycle and the slide then slams shut on the round as it is just 'hanging around' in the action.

I think this is why people that have 'problem child' 1911's (i.e. feeding problems) often report such good results with the Wilson magazines. The design is very 'forgiving' of ramp and throat issues. However, I have noticed that the Wilson magazines tend to 'push feed' quite often, which is something that I do not like at all.

In my personal 1911's, I only use two types of ammunition and only one style of magazine; The Federal 230 grain Hydra-Shok (or the new HST) and the Blazer (aluma case) 230 grain FMJ with the 7 round 'GI' style magazines. I also use the late style 'A1' firing pin stop radius with stock Colt recoil and main springs. All three of my 1911's, (two 1927 models and one 1917 model) work perfectly with this combination, so I just don't change anything.

I carry (5) 7 round 'Mil Spec' (circa 1954) magazines on-duty. I have carried these magazines for 9 years and they have only had the springs replaced once. When I replaced the springs, I used genuine Colt replacement springs, not super-trick Wilson or Wolff 'extra power' variants. I carry 230 grain Hydra-Shok (or HST now that Hydra-Shok) is being phased out) and I carry 230 grain Blazer aluma-case in my (4) supporting magazines for their light weight and hard surface penetration.

The theory is if you expend your first magazine, the likelihood that you will be engaged in a shootout with someone who is behind hard cover is quite likely and the FMJ would be superior in this theatre of operation.

P.S. Colt has officially told me that they Do Not measure recoil spring tension like Wilson, Wolff or anyone else and they do not publish the spring rates. I just order the stock Colt springs for a 5" Government Model...

[OD*]

I also use the late style 'A1' firing pin stop radius ..
Actually the FPS radius was changed around 6 years before the A1 pistol's debut, January of 1918.

[10851Man]

Thanks...I wasn't aware of the date...Robert

[kenhwind]

I for one feel that the factory rated mainspring is the way to go. If you have trigger pull problems replace the sear spring with a current Colt OEM sear spring.
I just replaced the sear springs in my Oldie Colties and you would think that I did a trigger job on these guns. Well the hammer and sear have been stoned and fit.

Recoil springs; well my guns have seen better days for sure but these babies work just fine. Eighteen # Wolf spring in my MKIV .45 and a shortened one in the MKIV .38 Super.

For some reason I cannot but think that the EGW FP stop is a solution to a problem that doesn't exist. And I do not think that it is supposed to be left square. It is designed to be custom radiused.

For some reason I don't seem to have, or have had, all these issues that some members have on this forum and I have owned over 30 different 1911 type pistols, mostly Colts and GMs.

[OD*]

And I do not think that it is supposed to be left square. It is designed to be custom radiused.
The originals weren't quite square either.

http://i206.photobucket.com/albums/bb274/OD1911/FPS2.jpg

[log man]

Well it solves more than one problem, and some experimenting at the same time. Certainly not necessary, but I'm enjoying trying different things just for the experience, you know like jumping in a mud puddle! For one it is a great way to stop extractor clocking. And on a Kimber it fills the square hole that the push rod can get stuck in or damaged by. Here's a Kimber, sorry for the excess TW25B.

http://i472.photobucket.com/albums/rr85/logpics/20090426_3.jpg

LOG

[kenhwind]

The originals weren't quite square either.
Thank you I never thought they were.
But all of the references are to the EGW Squared FPS.
Geometry, it won't work if its square.

[log man]

Thank you I never thought they were.
But all of the references are to the EGW Squared FPS.
Geometry, it won't work if its square.
Sure it will work it's located above the pin center so when the slide comes back it has to work and does, would be a bit harsher to the hammer, and would add more resistance to the slide coming back. Some guys run them that way. Fit one and try it before you put a radius on it. $15.00 :) of fun.

LOG

[OD*]

Thank you I never thought they were.
But all of the references are to the EGW Squared FPS.
Geometry, it won't work if its square.
Picture was just for informational purposes.

[1911Tuner]

For some reason I cannot but think that the EGW FP stop is a solution to a problem that doesn't exist.

Maybe better to think of the "New/Improved" stop with the current 7/32nds radius as the solution to a non-existent problem. A return to the original 5/64ths radius is a step in the right direction. John Browning really did know what he was doing.

Going smaller...to a 16th...enhances the effects of using a smaller radius there. I agree that it probably shouldn't be left dead square, though many do it to further delay the slide...without any apparent ill effects.

Moving in the other direction would allow the gun to be more easily tuned to function with "softball" target ammunition by increasing the slide's mechanical advantage in cocking the hammer and reducing the amount of force necessary to do it.

Look at it a quick and easy method of fine-tuning the gun to the chosen ammunition...very often without the added need of swapping out the recoil and mainsprings. Rule of thumb...The hotter the ammo, the smaller the radius.

Lastly...we should really start thinking of the recoil spring as an action spring, since its primary function is in stripping another round from the magazine and returning the gun to battery rather than controlling or limiting the slide's rearward velocity. That is more effectively handled by delaying it and bleeding off its momentum before the spring really even comes into play...during the peak of the recoil impulse. Slowing it after that point can only be done by upping the action spring's rate and tension...which causes recoil to be sharper. (Remember...The recoil system is a closed system, separate and apart from the barrel/bullet/breechblock. Once the slide starts to move, it begins an action/reaction event of its own.) The stiffer the spring, the harder it pushes on the slide AND the frame. (Force forward=force backward.) Also...the faster the slide moves and compresses the spring...the harder and faster the spring pushes back...against the slide and the frame. So, delaying and thus slowing the slide also slows the speed that it compresses the spring...and thus reduces the felt recoil that is caused by the spring. Delaying and slowing the slide means that it strikes the impact abutment in the frame with less force...which results in less muzzle flip.

In this day of raceguns...many tend to lose sight of the fact that the faster the gun runs, the wider the window for a malfunction opportunity. Rather than speeding it up...the better approach is to slow it down as much as is possible without compromising ejection, feeding, and a positive return to battery...and I'll say this again: If the gun needs an 18 pr 20 pound spring to feed and go to battery reliably...the gun still needs work. If it's right, it will function with an 8 or 10 pound spring...and I stand ready to prove it to any who are willing to make the trip to come see.

[kenhwind]

would be a bit harsher to the hammer,
Exactly! Aren't they 30 dollars from Brownells?
And yes I would try it, my Super needs a replacement anyway. One of these days.

[kenhwind]

I do believe that I posted a custom radius, and thanks for the input.
FEEDBACK! Psssst LOL

[log man]

Exactly! Aren't they 30 dollars from Brownells?
And yes I would try it, my Super needs a replacement anyway. One of these days.
Nope they are $15.00. I'm pretty careful not to blow any smoke . That can be seen anyway. :p

http://www.brownells.com/aspx/ns/store/ProductDetail.aspx?p=19627&title=1911%20AUTO%20OVERSIZED%20FIRING%20PIN%20STOP

LOG

[kenhwind]

You are correct, hmmm wonder where I got the 30 $ from, you know that thay have lot and los of goodies and you know that it might be hard to .........
:sleep:

[log man]

In this day of raceguns...many tend to lose sight of the fact that the faster the gun runs, the wider the window for a malfunction opportunity. Rather than speeding it up...the better approach is to slow it down as much as is possible without compromising ejection, feeding, and a positive return to battery...and I'll say this again: If the gun needs an 18 pr 20 pound spring to feed and go to battery reliably...the gun still needs work. If it's right, it will function with an 8 or 10 pound spring...and I stand ready to prove it to any who are willing to make the trip to come see.


Most race guns use a larger than standard radius and an 8#-11# recoil spring, the comp uses up the impulse so the guns sits flat. Opens and closes on target. Watch KC do a draw and hit five steel plates in the Steel Challenge in under 2 seconds and you'll be a believer. Whole different kind of shooting.

LOG