Outside diameter of USFA cylinder?

[jphendren]

Hello,

I am curious what the outside diameter of a USFA should measure?

On the webpage shown below, it is listed as 1.674" for USFA, and 1.652" for Colt.

http://www.gunblast.com/Ruger-NewVaquero.htm

I have a 3rd Gen. Colt, as well as a O.W. Ainsworth model that seems like it has the possibility of being built on an Old Armory Original Series frame.  When I measure my Ainsworth cylinder, it measures 1.650", which is smaller than the two figures listed above for either USFA or Colt.  My Ainsworth also has the rear sight shown on the Old Armory Original website, that is it has the long V into the sight trench.  From what I understand, that rear sight is only available on the Old Armory Original, and no other models including the Pre-War.  I realize that the blackpowder frame guns have a V notch rear, but this is different, as there is a long trench that flares into the V, and not just a V.  I have compared it to another Ainsworth, and the other Ainsworth definitely does not have this rear sight.

What do you guys think?  Could it be built on an Old Armory Original frame?

Jared

[Doc Sunrise]

Hi jphendren,

According to Jerry Kuhnhausen's Colt Shop Manual;

Colt's 1st & 2nd Gen. Cylinders may vary from a low of 1.645" to a high of 1.654", with the avearge being 1.650". 
1.650" was also the ordnance spec, with 1.645" to 1.654" being the allowable variation for commercial guns.

Colt's 3rd Gen. cylinders should measure 1.650" +/-.

Colt's Cowboy cylinder measurement averages 1.672".

He also states that 1.67" to 1.676"seems to be the average for replica Colts.

All of my Inspector Series guns averaged 1.672", and my Old Armory Original measures 1.650".  I suspect since the tooling for cylinders to be in the 1.650" measurement for the Old Armory Original, those sized cyliders are available for use in other guns.  The long trench ending in a "V" notch seems to be normal for all of my Black Powder framed guns.  However, if yours is different from that yet, one way to check if yours is an Old Armory frame is to measure the frame window.  My understanding is that the Old Armory's frame window is smaller than the original SAA's made by USFA.

[jphendren]

Thanks Doc Sunrise,

Here is an image of the rear site on my O.W. Ainsworth model.



I have a friend who also owns an Ainsworth model, and he has seen and fired my revolver, and his rear sight is definitely different than mine.  His revolver was built back in 2007, and mine was completed in August of 2010.  If you look at the Old Armory Original webpage, you will see this very rear sight shown.  My cylinder definitely measures 1.650", which is the correct measurement for an Old Armory Original cylinder.  What should the frame window measure on an Old Armory Original?

Jared

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[Doc Sunrise]

My "V" notch sights all look like yours.  What does your friends look like?

I measured my Inspector Series Guns and found the frame window to be 1.689" high and 1.763" long, where my Old Armory measured 1.685" high and 1.755" long.  Just for comparison, the Colt Shop Manual states 1st Gens. are 1.670" to 1.682" high and 1.76" to 1.78" long, and 2nd & 3rd Gens. are 1.665" to 1.676" high and 1.76" to 1.78" long.

My Inspector guns range from 2005 to 2007.

[jphendren]

"What does your friends look like?"

His only has the V notch, there is no long trench leading up to it.  Mine, sort of looks like a golf tee when looking straight down at it.  There is a thin cut that flares into the V at the rear of the frame.  To my knowledge, on other blackpowder framed USFA's, there is no thin cut, just the V at the rear.

Here is an image that I found on Gunbroker, it is the rear sight on an original 1881 Colt SAA, you can see the thin cut that leads up to the V.  Mine is exactly like that, the other USFA's that I have seen to best of my recollection were not.  Do your Inspector Series guns have this exact same rear sight?



I will measure my frame window and see what is measures.


Jared

[jdpress]

I am J.P. Hendren's friend.  This is the rear sight channel on my USFA Ainsworth - It does not have the elongated V-Channel leading up to the V-Notch.

J.D. Press

[Doc Sunrise]

OK!  I think I see what you are talking about.  At the bottom of the trench, there is a thin line, and it remains within the confine of the "V" notch for jdpress, but extends into the "U" trench for jphendren.

In looking through "A Study of the Colt Single Action Army Revolver", it shows rear sights like jphendren's gun on early 1st Gen. guns, with the shorter lined rear sight showing up much later.

My guess is in trying to more closely replicate the dimensions of the 1st Gen. USFA has even paid attention to this rear sight detail. 

[jphendren]

I have measured my frame window, but do not get the same measurements as Doc Sunrise for some odd reason.  I measured with a dial caliper, and tried to measure several times, but these figures are what I kept coming up with.

Frame window height = 1.667"

Frame window length = 1.750"

jdpress, great photographs by the way, and thank you for helping me illustrate what I was trying to say.

Jared

[Doc Sunrise]

jphendren,

I did say there were variations, and with my measurement taking, there are going to be variations.

 

[jphendren]

Doc Sunrise,

I understand that, and maybe my measuring system is not the most accurate.  I'd imagine that from revolver to revolver of the same model, that there will be slight dimensional differences.

Jared

[Doc Sunrise]

jphendren,

I am thinking that the most important thing to come away from this is that the current production Inspector Series guns are just a "little" better than before.  When I was trying to put a collection together, I chose the Custer gun to be my Ainsworth Inspector gun, so i am a little jealous of your Blue & Case Colored Ainsworth guns.

Also, I wasn't trying to imply anything, but I know when I ran down and took some quick measurements without removing the cylinders, my measurements were only close, and not precise by any means.

A couple of years ago I took a factory tour with Gary, and I left ther very impressed.  In just a short couple of years many new things have happened at USFA.  I think a new tour in the future is warranted.

 

[Capt. John Fitzgerald]

Jared,
The USFA web site has a pretty good picture that compares the standard size USFA cylinder to the "original series" cylinder (standard on left, original on right).  There is a noticeable visual difference between the two.  If you have a standard USFA you could do the side by side comparison yourself, or compare the USFA to a Colt cylinder.
There is a possibility that USFA, in order to fill your order in a timely manner, may have used an original series gun to make your Ainsworth.  They seem to make things up in batches and may not have had a standard BP frame on hand at the time your order was placed.  If so, you really lucked out!
CJF

[jphendren]

Hello Capt. John Fitzgerald,

I do have a 3rd Gen. Colt SAA that was built in 1997, and I compared the cylinders.  The USFA Ainsworth cylinder measured 1.650", and the Colt cylinder measured slightly larger at 1.653" if I recall.  After taking measurements, I am fairly certain that this Ainsworth is indeed an Old Armory Original.  Everything checks out.  I am not sure how it happened, but your explanation sounds as good as any.  I feel VERY fortunate to have this particular Ainsworth, it is the nicest revolver that I have ever owned.  I should also mention that this one has the fire blue screw package as well.  I did some accuracy testing with it the other day, and it actually outshot my Freedom Arms .454 Casull!  My best 5 shot group was 1.751" at 25 yards with my own handloads.

This revolver was a replacement for another Ainsworth that I ordered from the factory, that showed up with some issues.  I sent the original revolver back to have the problems repaired, and USFA decided to replace it.  This current Ainsworth is what came, and it is awesome in every way.  Great customer service!

Jared

[Virginia Gentleman]

Will a USFA cylinder interchange inside a Colt 1st, 2nd and 3rd generation frame window?

[Capt. John Fitzgerald]

VG,
The standard size USFA cylinder is too large to fit any of the three generations of Colt frames.
CJF