Colt Forum banner

1 - 13 of 13 Posts

·
Registered
Joined
·
183 Posts
Discussion Starter #1
I have been perusing some 2nd gen Colt single actions, and began to notice a lot of variation in the front sight post profiles.

I have noticed that (even amongst the same caliber) there appears to be difference in height and shape of the front sight posts (seeing this in some first gens too, just from going through the photos thread). Some (most) have a ramped shape, where the sight post is higher in the rear and slopes down. I have seen some that have a rounded hump shape that do not taper down. Some have a shark fin look, where the taper from rear to front is much more smooth (3rd gens seem to have a more consistent shark fin shape). I have seen several examples, and these ones do not appear filed.

Ramp (2nd gen 45):
NZqIqIu.png

Round hump (2nd gen 45):
JMba3NQ.png

Round hump (1st gen 45):
n5d6MaE.png

1st gen 44-40:
iEN8QjG.png

They all look a bit different to my eyes. Anyhow, I tried searching to see if there might be an explanation as to the different shapes - or if these were replacement sights? scanning through photos and the few I own, seems like 3rd gens are the most consistent in shape. I am seeing examples of the hump, or nub in the first and second gens, from posted photos.
 

·
Premium Member
Joined
·
4,399 Posts
Front sights of the 32-20 caliber are always lower profile and a tad more shark fin shaped in prewar single actions.

Somewhere around 1910 to 1911 on the other calibers the profile changed to the higher profile type front sight except for the later produced 38 colt and 38 special and 357 magnums that had a lower profile shark fin type sight.

I've tried to track when colt went from the rounded top type sight to the higher profile type and it's pretty hazzy but you start seeing the higher profile sights first around 1910 to 1911 in the 45's and 38-40's and 41's.

I believe it's because even after colt made the change on most of the guns it's like they found some of the older barrels and used them "or" I am seeing guns that have had their barrels changed out long enough ago that it's not a give away that they have been changed out.
 

·
Registered
Joined
·
1,768 Posts
Second gen sights were installed similar to a first gen, a key seat cut with a pre-shaped blank silver brazed in place. Each caliber had a different sight height based upon the center of the bore to the top of the sight. This was adopted from the first gen method of sight calibration, and it changed depending upon barrel length. The humped second gen sight is an alteration by someone, not a factory shape. In addition, the taper angle on seconds and thirds is shallower than that of first gens, and the sight base is larger.

JP
 

·
Registered
Joined
·
1,716 Posts
The round hump on the 1st Gen 45 looks altered to me. I can't comment on the 2nd and 3rd Gens, since have only owned one of these. It has already been pointed out that the 32-20 front sights aren't as tall as other the other calibers. The other calibers up thru about circa 1911 measure 0.29" tall. When fired with modern factory smokeless loads these always shot about 6" high at 25 Yards for me. About 1911 all sights for 41, 38-40, 44-40, and 45 Colt were raised to 0.34" tall. These later production SAA's shoot more to point of aim with smokeless.
 

·
Registered
Joined
·
183 Posts
Discussion Starter #7
Thanks for the replies guys.

I know the sight height varies by caliber, however I seem to see variance in height of the same caliber. Granted it may be my eyes and the angles of the photos.

I have seen a few examples of the ramped sights and of the oblong ovals - so difference in shape. This is where I was wondering if there may have been some sight profile alteration, though I cannot figure why someone would alter a sight to have the odd oblong shape.
 

·
Registered
Joined
·
2,111 Posts
"Each caliber had a different sight height based upon the center of the bore to the top of the sight." Wouldn't the center of the bore be in the same place no matter what the caliber was? Assuming the same barrel diameter, the center of the bore of a 32-20 would be in the same place as the center of the bore of a .45.
 

·
Premium Member
Joined
·
18,986 Posts
"Each caliber had a different sight height based upon the center of the bore to the top of the sight." Wouldn't the center of the bore be in the same place no matter what the caliber was? Assuming the same barrel diameter, the center of the bore of a 32-20 would be in the same place as the center of the bore of a .45.
John, I suspect that the jplower comment referred to how much distance there was from the edge of the center of the bore to the top of the sight. In other words, in a smaller bore like a 32wcf, the thickness of the barrel to the top of the front sight is the important factor. Therefore,
the larger the diameter of the bullet, the taller the front sight should be. However, to me, I would think that the trajectory of the bullet for a standard distance from the end of the barrel should also be factored in.
 

·
Registered
Joined
·
2,111 Posts
OK, I guess. "edge of the center of the bore" is not the center of the bore. No matter what the caliber, the center of the bullet goes down the center of the barrel, with equal amounts of the bullet above and below the center of the bore regardless of caliber. The smaller the bore diameter the lower the front sight would be a more accurate statement, because of ballistics or recoil (smaller calibers have less recoil with lighter bullets and a heavier barrel), rather than "sight height based upon the center of the bore to the top of the sight".
 

·
Registered
Joined
·
975 Posts
I took it to mean each caliber and each barrel length has a certain height the front sight is supposed to be and that in all cases the height is measured from the center of the bore.
 

·
Registered
Joined
·
1,768 Posts
I took it to mean each caliber and each barrel length has a certain height the front sight is supposed to be and that in all cases the height is measured from the center of the bore.
You, of course, are correct. My statement is, of course, based upon FACT. I have the factory sight chart from 1917 listing calibers, models, barrel lengths and sight heights FROM THE CENTER OF THE BORE.

jp
 

·
Registered
Joined
·
2,111 Posts
You, of course, are correct. My statement is, of course, based upon FACT. I have the factory sight chart from 1917 listing calibers, models, barrel lengths and sight heights FROM THE CENTER OF THE BORE.

jp
Assuming the barrels are of the same diameter, the center of the bore is going to be in the same place for a .45 as it is for a .32. You originally stated "Each caliber had a different sight height based upon the center of the bore to the top of the sight". I guess you did not mean based upon, but meant measured from, and were just talking about sight height specs. Sight height is not based upon the bore diameter, or center of the bore, but more likely is based upon ballistics, barrel length, and recoil.

If ballistics, bullet weight, and caliber are the same, why would smokeless loads need a different sight height than black powder loads?
 
1 - 13 of 13 Posts
Top