My experience is similar to all of the above. Modern, well designed HP's that tend to mimic the general ogive of original FMJ ammo will load fine and without effort. I haven't tried the Gold Dots in particular, but modern Speer products should fit that bill exactly. Likewise, even a LSWC bullet loaded to the proper shoulder and OAL dimensions will mimic the FMJ round on the critical parts of its ogive where it contacts the ramp and barrel and will load fine.
In real world experience, I currently have three pre- '80 guns. Two Series '70 guns, a '74 and an '80, and I also have Sistema Colt 1927 model from 1956. All three of these guns will run LSWC, ball, RNL, and HP without a hiccup. None of these guns have been "throated," "Polished," flared/lowered, or had their extractors tuned (at least on my watch - tested, but not tuned as all were fine and run fine). One of these guns is not even broken in and is near-new, the other two have seen military and law enforcement use before I acquired them and have pretty high round counts.
After several years of experimentation, I have also settled on using only Colt OEM magazines, 7 rd., with their "Hybrid" feedlips. In addition to those magazines, I have about three or four "vintage" magazines, meaning genuine WWII or earlier GI or Colt style magazines with the tapered feed lips. Against my initial expectations years ago, these magazines feed those guns just as well. I have had uneven success with Wadcutter feed-lipped magazines, and that includes Wilson type. All magazines I have from other manufacturers are now gone, and these Colt/Colt OEM and GI magazines also run 100% in my other (80 Series Colt and other non-Colt) 1911s. In a sense, 1911 magazine Nirvana - any magazine, any load, any gun. Bliss.
HMMurdock, if your interest in a "Series '70" is to get a real one, you should know the current Colt "reproduction" is as much a true "Series '70" as a fish is a bicycle. The current repro is just a current Series 80 minus the firing pin safety - it has the same barrel, bushing, and sights as an 80, they've just removed the firing pin safety and made a few other cosmetic changes, such as the trigger, MSH, hammer profile and slide roll marks. The real heart and soul of a Series '70, the tapered Mk IV Series '70 barrel and the "Accurizing" collet bushing, are missing. The sights are also wrong and the blue finish is a pathetic facsimile of the high polish Colt Blue of a fresh Series '70. Where the gorgeous checkered walnut medallion grips went on the repro, I haven't a clue, but the repro comes with cheap rosewood plain grips. Overall, it's just not even close to the real thing.
If you are debating between the two, I strongly suggest you find a mint or better original Series '70, and you can do so for less than a current reproduction costs retail in most cases. To inspire you, this is a mint one I bought last winter have as a "keeper" while my other well-worn one continued to do periodic holster and saddle time.
military contract mags stamped with a contract number of 1M291
You need to use caution with these, too. They are now faked widely and available "new" online and at guns shows. They have been out of production for about 25 years, so when you see them available new in the fresh brown wrapper for $12 or less, you really need to ask yourself if that makes sense, or if boats from China are delivering them regularly. Real ones will show some wear and not be dirt cheap. Impact Guns sells Colt magazines online cheaply, and Metalfrom usually has a colt OEM equivalent available on sale or in bulk. Cheap no-name magazines are your fastest route to problems.
welcome to the addiction-
