what is different with 1911's, series 70 and 80

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Dec 27, 2002
SE Quad, Penns Woods
Trying to find a beavertail for my Sistema Colt. Found the one that I want but only shows for series 70 and another for series 80 Colts. Is either one of these the right one for the Sistema ? An I correct that a series 70 is a "normal" 1911 ?

The primary difference between the Series 70 and the Series 80 was the addition of a firing pin safety asssembly to the later model. What you require would be something for a Series 70 (or pre-Series 70), model. Keep in mind though that some hand fitting and recontouring of the frame may be needed to make the new beavertail safety fit.
The above advice is correct, so I'll boot in an additional word or two:

1) you're in the revolver forum, and a lot of these guys wouldn't know what a Sistema Colt is if it landed on their foot. ;)

2) I'd hold off a bit on modifying it. The Sistemas, while never as desirable as Colts of that vintage will be, are interesting. If yours is near stock, I'd almost suggest keeping it that way. Especially if yours is pre-War. With the trend towards spiraling costs of unmodified Colts, Sistemas will get dragged up eventually if in stock form, and already have. They have doubled in value in the last six years or so.

3) The basic tang safety just isn't that bad. I have several 1911s, most with high-ride beavertail safeties. I recently bought an unmolested, real-deal Colt Series 70. Shooting it is every bit as much fun as my more expensive and modified custom Caspians. The GI sights are a little bit of a pain, but the tang safety is not a complaint. All I do is not ride my right thumb over the slide safety as we were all taught to do in the '80s to copy the IPSC/IDPA competitors. Just use a normal grip and it's fine. Muzzle flip is just not that much worse, unless you are trying to hit six speed plates in a row timed. And you shouldn't be using a Sistema for that (see below).

4) of course, if your Sistema is already modified and gussied up, do what you want with it. But nice "pre-Series 70" (which the Sistemas are) are just fine for shooting and are real Colt copies on their machinery.

5) If your goal is to build a tighter, more competitive gun, keep in mind that the steel in Sistemas is softer, and with heavy use going to wear faster and defeat much of your investment in customizing much faster than if built on a Colt, Caspian, or even Norinco base.

So, my general opinion is to resist the temptation to "trick out" a Sistema and instead to just enjoy a "pre-70" colt the way JMB intended (except for those silly 1923 mods, of course).
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Wow. Totally messed that up. Was flipping tabs on internet browser and lost my place on THR. As for the mods to the gun the beavertail is a must. I have big hands and gripping it with getting in the bite is almost impossible. The beavertail safety is the only thing that I was going to modify other than a new finish and some drop in parts, springs etc. Had not thought about running it at a steel match. But that does not sound like a bad idea.
Wow. Totally messed that up. Was flipping tabs on internet browser and lost my place on THR.

Yeah, no worries. We all do it once in a while!

Now, here's my main complaint about your post:


Love to see pics of it!
sorry bout that

I forget sometimes. I did not get to shoot it yet. Had it for a whole 2 days and no range time. Bummer. Tomorrow will be 94 + degrees so it will not take long to warm it up.


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OH, Riss,

Seriously, that is worth keeping un-messed with. Looks all stock.

1) What is the S/N? Have you tried to date it yet between 1927 and 1960 when they were made?

2) The bluing is all gone, but it doesn't look pitted, so it could be re-done for a few hundred to perfection.

3) I would save any money you want to spend on it, put it into a kitty and when you get to 200, get a master blue job done on it and make it like new. better than spending money on bells and whistles.

What are you into if for and what are your goals? do you have other .45's, or have experience with them?
The real answer about the difference between Series 70 and Series 80 from the 1911 forum:

It was during (1971) that Colt introduced the first major design change to the Government Model in nearly 50 years. In an attempt to improve the accuracy of production guns the barrel bushing was redesigned, along with the barrel. In this system the bushing utilized four spring-steel "fingers" that gripped the enlarged diameter of the muzzle end of the barrel as the gun returned to battery. By tightening the fit of barrel and bushing in this manner Colt was able to improve the accuracy of the average production gun, without going through the expense of hand fitting the older solid barrel bushing to the barrel and slide. Models using the new barrel/bushing setup were the Government Model and Gold Cup, which were designated the "Mark IV Series 70" or simply Series 70 pistols. It should be noted that the shorter 4 1/4" barreled Commander pistols retained the use of the older solid bushing design and thus were never designated Series 70 pistols, although one hears the term erroneously applied to Commanders from time to time.

The new "collet" bushing (as it came to be known) worked quite well, however it was prone to breakage if the inside diameter of the slide was too small as it caused the fingers to buckle, then later break from the stress of being wedged between the barrel and slide. On pistols with oversized slides the bushing didn't grip well enough, and accuracy suffered. Because of this the collet bushing was eventually phased out sometime around 1988, with the older solid barrel bushing design being reinstated for use in production guns.

The single biggest change to the 1911 design came about in 1983, when Colt introduced the "MK IV Series 80" pistols. These guns incorporated a new firing pin block safety system, where a series of internal levers and a plunger positively blocked the firing pin from moving until the trigger was pressed, thus eliminating the possibility of the gun discharging if dropped onto a hard surface or struck hard. In this instance however, ALL of Colt's 1911-pattern pistols incorporated the new design change so even the Commander and Officer's ACP pistols became known as Series 80 guns. With the previous paragraph in mind, it is important to know that from 1983 until 1988 the early Government Model and Gold Cup Series 80 pistols used the Series 70-type barrel and bushing as well, although they were known only as Series 80 guns.

There was one other design change made to the Series 80 guns as well, and that was a re-designed half-cock notch. On all models the notch was changed to a flat shelf instead of a hook, and it is located where half-cock is engaged just as the hammer begins to be pulled back. This way the half-cock notch will still perform its job of arresting the hammer fall should your thumb slip while manually cocking the pistol, yet there is no longer a hook to possibly break and allow the hammer to fall anyway. With the notch now located near the at-rest position, you can pull the trigger on a Series 80 while at half-cock and the hammer WILL fall. However, since it was already near the at-rest position the hammer movement isn't sufficient to impact the firing pin with any amount of force.

Regarding the "clone" guns (1911-pattern pistols made by manufacturers other than Colt), only Para-Ordinance adopted Colt's Series 80 firing pin block system as well. Kimber's Series II pistols and the new S&W 1911s have a FP safety also, but it is a different system than Colt's and is disabled by depressing the grip safety. No manufacturers aside from Colt ever adopted the Series 70 barrel/bushing arrangement, so technically there are no "Series 70" clone guns. What this means is that design-wise most of them share commonality with the pre-Series 70 guns, using neither the firing pin block NOR the collet bushing. Because of this it is important to remember that only Colt Series 80 models, and a couple of "clone" 1911 makers use a firing pin block. Older Colts and most other clone guns lack a firing pin safety and can possibly discharge if there is a round in the chamber and the gun is dropped on a hard surface, or if struck a blow hard enough to allow the firing pin to jump forward and impact the primer of the loaded round. By the way, Colt has just recently reintroduced new custom pistols lacking the S80 firing pin safety (called the Gunsite models) as well as a reintroduced original-style Series 70 to appeal to purists. Interestingly, the latter uses a solid barrel bushing and Series 80 hammer, so it is somewhat different mechanically than the original Series 70 models.
Looks like "loop" copied a lot of crap from another site instead of formulating an intelligent response of his own. Make up your own mind and don't let the volume pollution he's thrown in make a difference.
I copied the facts that are the difference between the Series 70 and the Series 80.

No one else here actually addressed the real differences.

Since someone else took the time to put them into print and I remembered them I did not think it worth my time to rewrite them and pretend they were my own.

Maybe if you read it, kamerer, you'll learn something.

Maybe if you reblue it and call it your own it will be worth something.
To answer the question, I have another 1911. A nice little custom, SA commander. Feels too small to shoot all of the time. Wanted a full size to work on, take apart, work on some more, and possibly shoot a little. If I really like the platform I will get another one that is worthy of collecting. This one is banged up a little, and as you can see has about 3% of the finish left. A nice little parkerize job, either then painted or just soaked in Cosmoline and left to go green.
Loop- thank you for that information. I had been wondering what the difference was as well. :) Do the Springfields and/ or the Sig m1911s have a firing pin safety?
To my knowledge the SIG and the S&W both incorporate the firing pin safety. I pretty much focus on pre-Series 70 guns so I can't say for certain because I don't own either a SIG or S&W 1911. But, I have read about issues with the firing pin safety in both guns on the 1911 forum. I am not sure if they used the Colt or Kimber system or developed proprietary systems.

The 1911 forum does have both SIG and S&W boards. Those would be good places to research those questions. The address for the forum is: http://forum.m1911.org/

To clarify, all pre-Series 70 guns will interchange all standard 1911 parts except the bushing, slide and barrel. It seems barrel exterior tolerances were somewhat relaxed for the Series 70 as near as I can tell.

TY for the kind words. I apologize for kind of going off, but I was just trying to be helpful.

Good info. And it has been my experience with Series 70 pistols that sometimes tolerances were rather loose when comparing several guns made at the around the same time. Back then, Colt really didn't have much if any competition in the M1911 market, so I don't think they were all too concerned about tolerances on standard grade guns. Probably because they knew they would sell everyone they made, and still not be able to meet the demand for them.
kamerer Looks like "loop" copied a lot of crap from another site instead of formulating an intelligent response of his own.

Its comments like this that absolutely make my jaw drop. What is the matter with you that you would think that statement has any usefulness, any constructive positives or is even remotely appropriate in a social context? It is rude, arrogant, judgmental and serves no purpose. Its a statement expected and tolerated of a teenager but is without merit for an adult. It disqualifies your legitimacy and causes readers to suspect your maturity in anything you have to say. As most of us learned in Kindergarten: if you don’t have something nice to say, don’t say it. I suggest you take a Dale Carnegie course or find yourself a therapist as I would suspect you are either 1) a teenager who will someday need to keep a job, or 2) you’ve already been married at least once and your current marriage is on the rocks.
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