Colt GM MkIV


December 23, 2002, 04:22 PM
Sometime in the '80s I bought a new series 80 Colt GM with MkIV rollmarked on the slide. I have ever since thought that MkIVs were all series 80's but it recently come to my attention that at least some series 70's are also marked MkIV. Just what denotes a MkIV? Are the Series 70 MkIVs transition models? TIA

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December 24, 2002, 03:41 PM
Both Series 70 and 80 are Mark IV. Guess they got a charge out of watching "Dragnet," or sumpin.

The big change in Series 70 was the collet bushing. Don't know for sure but think Series 80 started the trigger operated firing pin safety. The Series 80 for a time had the collet bushing then reverted to the solid, old fashioned bushing. HTH

December 24, 2002, 03:55 PM
Out of the closet and onto the desk, my own, personal CGM MKIV, series 70, purchased to carry as a medic back when I played Army.

At HHB 1/75 FA I might have been authorized to carry a .45, but, somehow, there was never one available, the officers getting the cream, and this was my response, for (stupid) FTX's.

Anything that seemed real, I grabbed an A1/M203 combo, and, with all the stuff I carried, skipped the .45.

Anyway, memory lane negotiated, I had to have bought it around '72, but it couldn't have been any later than '74, when I finally regained my current rank: PFC (Proud F****** Civilian).

Good weapon, and it hasn't been fired in at least five years, so thanks for the reminder. Still won't be fired 'till spring, though: snow on the ground and another foot coming, and I HATE digging to find all 50 rounds of expended brass for the reloading process....

December 24, 2002, 04:54 PM
I guess my CRS is getting worse. I owned a S70 in the seventies that was later stolen, hence the S80 puchase. I remember when I bought the S80 I thought the big MkIV roll-marked on the slide looked odd (billboard like). Just didn't remember the S70 being so marked and so thought it was a new designation and never made much more about it. Oh well, I stand corrected. :(

December 24, 2002, 07:13 PM
Has anyone mentioned that Mark Ivey (IV, get it) used to work at Colt?

December 24, 2002, 07:29 PM
Yeah, riverdog, but I don't buy it. How about the MkIIIs and MkVs? ;)

December 24, 2002, 10:13 PM
I still have my Mark IV 70 Series that I bought in the 70's when stationed at Sheppard AFB, Wichita Falls, Texas.

Still shoots great. Don't fire it much as I have 3 other 1911's.

It is the nicest finish of the others though.


Bottom Gun
December 26, 2002, 09:39 AM
As I recall, the early Series 70 guns had solid bushings. They were followed by the Series 70 Mark IV's which had the split collet barrel bushing.

I bought a new Series 70 Mark IV in 1971 and paid the full retail price of $125 for it. I've owned several Mark IV's and my experience with them is that they didn't shoot as accurately as the solid bushing guns.

I bought a Series 80 six or seven years ago. It had a solid barrel bushing and that wonderful firing pin safety. It shot better for me than the Mark IV's did.

December 26, 2002, 10:08 AM
As some already know, the Series 70 was actually a cheapening of the manufacturing process from the GMs that preceded the change. The spring bushing, cheaper finish etc. were manufacturing shortcuts. It's interesting to see folks now who eagerly seek out Series 70 as superior Colt automatics.

The Series 80 imho is better than most of the original Series 70 or at least no worse. I have owned a number of 80s with absolutely impeccable fit and finish and operation.

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