[T.May]

New in the original Custom Shop box, Colt Nation Match, MK IV, Series 70 barrel in .45 ACP

 

[kenhwind]

Those MK IV Series 70 barrels seem to be a desirable item, I've seen some that were NIB or LNIB sell for a nice sum on eBay.

 

[Restricted]

Very Cool Find

 

[MtnSpur]

So THAT is how they sold em. I bought mine with a firearm wrapped around it. This leads me to ask: Were barrels and collet bushings matched at the factory or were the tolerances close enough +/- that any barrel and bushing from the same manufacturing run would be good to go? Thinking the second but perhaps there is insight of which I am unawares.

 

[JohnnyP]

The collet bushing was introduced to do away with the hand fitting required for a tight barrel to bushing fit.

 

[MtnSpur]

The collet bushing was introduced to do away with the hand fitting required for a tight barrel to bushing fit

Of that I'm aware, the question was: due to tolerance(s) were barrels and collet bushings matched for fit ? (assuming they were out of the same floor production run). It's the design engineer background in me that has seen fit failures even during same period manufacturing floor operations that prompts this question. (The ole ANSI Y14.5 tolerancing specifications etc).

 

[JudgeColt]

Of that I'm aware, the question was: due to tolerance(s) were barrels and collet bushings matched for fit ?

No. The "spring-loaded" fingers of the collet bushing eliminated the need for fitting. The "springs" took up any tolerances.

 

[JohnnyP]

Of that I'm aware, the question was: due to tolerance(s) were barrels and collet bushings matched for fit ? (assuming they were out of the same floor production run). It's the design engineer background in me that has seen fit failures even during same period manufacturing floor operations that prompts this question. (The ole ANSI Y14.5 tolerancing specifications etc).

There would be no matching of the collet bushing to a particular tolerance barrel or vice versa. The spring fingers of the collet bushing provided the correct tolerance.

Another time capsule from WWII.

 

[dakota1911]

Nice time capsule finds.

 

[T.May]

So THAT is how they sold em. I bought mine with a firearm wrapped around it. This leads me to ask: Were barrels and collet bushings matched at the factory or were the tolerances close enough +/- that any barrel and bushing from the same manufacturing run would be good to go? Thinking the second but perhaps there is insight of which I am unawares.

I'm looking for the rest of the gun to go with it