Besides  the difference in the angle of the rear cocking serrations and the Springfield stamp on the mil-spec, is there any difference between these two guns?

Quite a few differences.  The Milspec has taller sights, a lowered and flared ejection port, usually a stainless 1 pc. barrel with stianless bushing, a thicker dust cover, a thicker frontstrap, black plastic grips, and no lanyard loop on the mainspring housing.

The GI has WWII era small sights, a regular, non lowered and flared ejection port, a 2 piece barrel, a Colt profiled front strap and dust cover, walnut grips, and a lanyard loop.

I believe the Mil-spec will also have a lowered/flared ejection port, more beveled mag well, and larger sights.  My NM (not national match/denotes most work performed in U.S./no Brazil stamp) model also came w/ stainless bbl. & bushing and commander hammer instead of standard spur hammer.  HTH.

Yup, no bevel on the GI magwell.

So If I want a no nonsense shooter for now (but can also be modified at a later dateas time and funds allow) , the best way to go is the Mil-spec I take it.  Looking at a stainless right now.

Quoted: Quite a few differences.  The Milspec has taller sights, a lowered and flared ejection port, usually a stainless 1 pc. barrel with stianless bushing, a thicker dust cover, a thicker frontstrap, black plastic grips, and no lanyard loop on the mainspring housing. The GI has WWII era small sights, a regular, non lowered and flared ejection port, a 2 piece barrel, a Colt profiled front strap and dust cover, walnut grips, and a lanyard loop.

Not all Mil-Specs have hte 1 pc barrel/stainless steel bushing.  This is only found on the "NM" prefix serial numberd ones.  All of the "N" prefix guns have a 2 pc. barrel and carbon steel bushing.

Quoted: So If I want a no nonsense shooter for now (but can also be modified at a later dateas time and funds allow) , the best way to go is the Mil-spec I take it.  Looking at a stainless right now.

Actually, not really.  You get a better barrel (sometimes, depending on the serial number prefix, as Nationwide mentioned), better sights, and the ejection port.  The other stuff, like the cocking serrations, and the frontstrap and dustcover contours, are a personal preference thing.  However, the cocking serrations cannot be changed.  Even though it's minor, if you like vertical ones, get the GI instead.

I say this because the ejection port and barrel are a moot point, and sights are an easy thing to change.  Remember, we can put that Series 70 Colt barrel in it, which I would take over a Springfield stainless barrel, personally.  I can lower and flare your port and put on new sights in a matter of 30 minutes.  Either way makes no difference to me, but whatever avantages the Mil-Spec has in a few features is of no consequence, since you have a smith that works for free.

If you're going to customize, I personally like the GI better as a base gun.  It has the classic lines of the Colt.  Though I love Springers, some of the things I don't like about them cosmetically are the frontstrap and dustcover contours, and those non vertical cocking serrations.  If you do not share these tastes, and want to pick up a slightly better gun out of the box, get the Mil-Spec.  

Taken from 1911 Forum:

"
WW2 (GI) Model: Pistol closely replicates the basic 1911A1 as used by the US military for seven decades. Features:

   * high wall ("narrow") ejection port
   * low profile GI sights
   * lanyard loop on mainspring housing
   * vertical cocking serrations on slide


Mil-Spec: Pre-dated the G.I. model, adds some popular features/upgrades

   * stainless barrel and bushing (some models)
   * loaded chamber indicator (some models)
   * lowered and flared ejection port
   * high profile 3-dot sights
   * beveled magazine well
   * loss of the lanyard loop on mainspring housing
   * forward-raked cocking serrations on slide
"
There ya go!

I just got a GI and it has a one piece barrel as far as I can tell. whats the difference between the one and two piece?

Quoted: I just got a GI and it has a one piece barrel as far as I can tell. whats the difference between the one and two piece?

The two piece barrel is made from two pieces welded together.  If you look on the bottom of a new one, just ahead of the lower lugs, on the two piece you can see a small staking mark.  Most times, you can also see a faint seem from the weld.  My two piece barrels have been fine and accurate, but I prefer to replace the barrel anyway.

Quoted: sights and the ils in the mainspring housing of the springfield.

My "NM" prefix mil-spec has the "ILS" (lock) just like my GI--in fact the mil-spec I bought was the first  time I ever saw it.
Something I find interesting is my micro GI is quite a bit more accurate than my mil-spec, just not as fun to shoot much.

ETA: I sold off a full size GI, figuring I had the bases covered with the mil-spec and micro, sorry I did now

So the Mil-Spec is a better out of the gun box because of the lowered ejection port, higher sights. beveled mag well and possibly a one piece barrel if it has the NM prefix to the serial number?  

John, what exactly is different about the contour of the front strap and dust cover than the series 70 I have?

how long would it take and how difficult to fit that colt barrel to a springer? Also the Brazilian stamped pistols, i read those forgings are made by Imbel and the fitting is still done in the states, and  that they are still quality , is that true?

Quoted: So the Mil-Spec is a better out of the gun box because of the lowered ejection port, higher sights. beveled mag well and possibly a one piece barrel if it has the NM prefix to the serial number?   John, what exactly is different about the contour of the front strap and dust cover than the series 70 I have? how long would it take and how difficult to fit that colt barrel to a springer? Also the Brazilian stamped pistols, i read those forgings are made by Imbel and the fitting is still done in the states, and  that they are still quality , is that true?

Adam, I've worked on a lot of Springers.  People get hung up over little details, like 1 or two piece barrels, whether it was mostly assembled here, or in Brazil, or whatever.  My opinion is that it does not really matter.  Springers have good quality frames and slides, okay barrels, and and some internals that are marginal.  The truth is, it does not matter for you, since I'll go through the gun and make sure it's all up to par.  I doubt there will be anything that is so bad that I can't have the entire gun done in a couple hours.  

Now, on the GI, the contour of the dust cover and frontstrap is roughly the same as the Colt.  On the Mil-Spec, the contour on the dust cover has a less pronounced radius, since it's thicker.  The frontstrap is also less pronounced, or curved.  It is also thicker.  Springfield did this so that there was extra material in these areas to accomodate a scope mount and checkering.  If you never noticed it before, then it should not be an issue.  It's one of my little pet peeves with regards to cosmetics, but that's about all it is.  

Don't get to bothered by where it was assembled, which is better, etc.  If you were going to leave the gun stock, I would tell you to get the Mil-Spec, but you're not going to leave the gun stock.  You're probably eventually going to do some minor mods that might include a beavertail, commander hammer, trigger, sights, etc.  If that's the case, then get the gun that looks nicer, or is just plain cheaper.  

Consider this:  you can get the GI, save like $70 over the Mil-Spec, spend $100 in parts, and get Novak sights front and rear, a Greider trigger, an S&A beavertail, and an MGW hammer.  I'll install the sights, carry bevel the exterior, lower an dflare the ejection port, do a reliability job, install the hammer and trigger, put in the beavertail, bead blast it, and have it done in about 5 hours.   Just a thought.....

I have both.

My nontechnical opinion is that the GI looks cooler but the mil-spec is all business.

So, it depends on what you want.  If you have a safe full of 1911s, get a GI.  If you want an all purpose and functional shooter, get the milspec.

Well John I just placed a Springer Stainless GI on order through Impact Guns out of Utah.  Its not in stock so I'll probably take delivery from them around the same time I get my Colt back from you.  I remember how long it took for them to send my Les Baer AR lower!  Hopefully it won't be to long though.  What do you think Novaks or Heinies in the black?

Quoted: Also the Brazilian stamped pistols, i read those forgings are made by Imbel and the fitting is still done in the states, and  that they are still quality , is that true?

ALL of the forgings are made in Brazil.  The NM s/n pistols are final machined here in the US, while the others are final machined in Brazil, then assembled here.

Quoted: Now, on the GI, the contour of the dust cover and frontstrap is roughly the same as the Colt.  On the Mil-Spec, the contour on the dust cover has a less pronounced radius, since it's thicker.  The frontstrap is also less pronounced, or curved.  It is also thicker.  Springfield did this so that there was extra material in these areas to accomodate a scope mount and checkering.  If you never noticed it before, then it should not be an issue.  It's one of my little pet peeves with regards to cosmetics, but that's about all it is.   Don't get to bothered by where it was assembled, which is better, etc.  If you were going to leave the gun stock, I would tell you to get the Mil-Spec, but you're not going to leave the gun stock.  You're probably eventually going to do some minor mods that might include a beavertail, commander hammer, trigger, sights, etc.  If that's the case, then get the gun that looks nicer, or is just plain cheaper.   Consider this:  you can get the GI, save like $70 over the Mil-Spec, spend $100 in parts, and get Novak sights front and rear, a Greider trigger, an S&A beavertail, and an MGW hammer.  I'll install the sights, carry bevel the exterior, lower an dflare the ejection port, do a reliability job, install the hammer and trigger, put in the beavertail, bead blast it, and have it done in about 5 hours.   Just a thought.....

Obviously Hobbs has a lot more experience than I do, I just wanted to add a couple things.  First, I agree with him that neither one is a bad gun.  I've had both and currently have 3 MS, 2 are NM frames and 1 is not.  I do think the NM numbered guns tend to have a better "feel and fit", but that is subjective.  

One thing I've noticed in the last year or two, I believe SA has changed the radius on the front strap.  My newest MS has a contour much closer to a Colt than the older guns did.  I'm not positive it is the same as Colt, just closer than it used to be.

You're absolutley correct about the frontstrap.  It is closer to the Colt, but not the same.  It's a little more curved, but still not as much as Colt, and it's still thicker.  I checked out a current Mil-Spec yesterday, and it has the more curved frontstrap.  

Quoted: Well John I just placed a Springer Stainless GI on order through Impact Guns out of Utah.  Its not in stock so I'll probably take delivery from them around the same time I get my Colt back from you.  I remember how long it took for them to send my Les Baer AR lower!  Hopefully it won't be to long though.  What do you think Novaks or Heinies in the black?

I guess it depends on what you like.  I like the Heinies, but most like the Novaks better.  The Heinies take me about twice as long to machine, but I don't mind if you don't.