M1 carbine sight question

lrrifleman

lrrifleman

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I have a minor dilemma, and it has me a little confused.

I have an M1 Carbine that has the end of war style fully adjustable rear sight. My rear sight is for all practical purposes, useless. I would like to replace it with an early war style "L" flip sight.

Here is my confusion. The adjustable sight seems to be cut with a female dovetail slot, riding on a male dovetail. However, the "L" sight appears to have a male dovetail that would fit into a female dovetail on the receiver.

My question: is there an adapter base for the carbine's receiver, is there a female dovetail space (either ahead or behind) the receiver's male dovetail, or did the receiver have to be remilled during the arsenal rebuild to accommodate the adjustable sight?

Thanks in advance for your help!
 
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Your "Male/female" has me a little confused! Just remember that the rebuilding process that almost every M-1 went through was a simple parts change! There was no machining done (with the exception of refinishing/bead blasting).

On the other hand, why not just rebuild the Lyman sight? It is a better sight.

Another option would be a No-drill scope base, it uses the rear sight dove tail and has a Weaver type base about 4" long cantilevered over the bolt. (so it is "In-Line" with the bore axis.)

Over the years I have owned 15 or 20 M-1 Carbines. I have used several systems of scope mounts: The Redfield T-3 system for inferred scopes requires massive modifications, The Universal brand copies of M-1's used a side mount Weaver 2 part base. The No drill mount.

My current No Drill is cast/forged steel and maid in Spain without any manufacturing name. With the last 2, you can use a red dot or a magnifying scope of any brand.

Ivan
 
lrrifleman said:
I have a minor dilemma, and it has me a little confused.

I have an M1 Carbine that has the end of war style fully adjustable rear sight. My rear sight is for all practical purposes, useless. I would like to replace it with an early war style "L" flip sight.

Here is my confusion. The adjustable sight seems to be cut with a female dovetail slot, riding on a male dovetail. However, the "L" sight appears to have a male dovetail that would fit into a female dovetail on the
My question: is there an adapter base for the carbine's receiver, is there a female dovetail space (either ahead or behind) the receiver's male dovetail, or did the receiver have to be remilled during the arsenal rebuild to accommodate the adjustable sight?

Thanks in advance for your help!
Click to expand...

You don't need any type of adapter, the adjustable rear was designed to fit in the same dovetail as the earlier "L" sight. It is open to allow for it to be securely staked in place to prevent it being knocked out position in use and that, combined with the rest of the base being slightly raised is probably the source of your confusion.

If you go to replace it be sure to drive the old one out from the left and install the replacement from the right as the dovetails were cut slightly tapered to make them more secure in use. The adjustable sights tend to be rather heavily staked in place and can be hard to remove (though once in a while you get one with the opposite problem, when I was actively collecting M1 Carbines had a couple so loose they almost fell out!).
 
I have never seen any reason to replace the postwar carbine click adjustable rear sight. It seems to work fine for me, except the elevation markings differ from reality. I well remember replacing an issue rear sight on a M1903A3 rifle nearly 50 years ago. It is fairly similar in design and mounting as the later Carbine rear sight. I had to cut that rear sight off the dovetail, no other way to get it off, and I tried everything. It was a serious mistake for me to continue once it was evident that it was mounted to stay in place forever. I thought it could be easily removed and replaced later if I decided to do so. How wrong I was.
 
There are basically three types of USGI rear sights for the M1 carbine; the original "L" flip sight, the milled adjustable sight, and the stamped adjustable sight.

All three are designed to slide into the receiver dovetail. Often times the original sight installed on the gun is not required to be staked in place, but more often than not any replacement sight was required to be staked.

The adjustable sight (milled and stamped) was designed as an improvement over the flip sight.

It would be interesting to hear more detail on why your current rear sight is "for all practical purposes, useless." Reverting to a flip sight is not necessarily an improvement.


m1crbsit.jpg


25jz6ed.jpg


cinlandrearsight2.jpg
 
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M1 Carbine

The Military converted all they could find to
new adjustable sights and bayonet lug.
Original parts are expensive when you can
find them. Be careful you don't get sold
a repro at original price. Lots of cheap repros out there.
I have repros on my Saginaw, and manage
to live with it.
I agree that the adjustables are better if you
are really going to shoot at stuff.:confused:
 
Determine what you have, before you go and change anything. Late war guns were supplied with the milled adjustable rear sights.

It would be a good idea to post some photos. Most Carbines were rebuilt, but not all were. It would be a crime to remove an original rear sight.
 
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One other thing to consider... The carbines were zeroed by filing the front sight to the desired point of impact. Changing the rear sight back to a flip may require also changing the front sight as well.

I'm curious as well as to what is the problem with the currently installed rear sight.
 
lrrifleman said:
It's an Iver Johnson, not an original GI Carbine.
Click to expand...

I believe Iver Johnson used a commercial version of the Military rear sight. Perhaps you can move the sight in it's dovetail to correct the windage. . I.E. center the adjustments and move the whole sight to the right in it's dovetail. That should gain you some adjustability
 
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Faulkner said:
There are basically three types of USGI rear sights for the M1 carbine; the original "L" flip sight, the milled adjustable sight, and the stamped adjustable sight.

All three are designed to slide into the receiver dovetail. Often times the original sight installed on the gun is not required to be staked in place, but more often than not any replacement sight was required to be staked.

The adjustable sight (milled and stamped) was designed as an improvement over the flip sight.

It would be interesting to hear more detail on why your current rear sight is "for all practical purposes, useless." Reverting to a flip sight is not necessarily an improvement.


m1crbsit.jpg


25jz6ed.jpg


cinlandrearsight2.jpg
Click to expand...


Faulkner, thanks! Your rear sight profile pictures clarified my dilemma. I have a few loose milled carbine rear sights in my parts bin, and I was viewing the recess closer to the windage knob as the point of attachment, not the front of the sight base.

Since I live in a state that has outlawed the carbine since about '92 unless it was registered as a target rifle, I can't get a new-to-me carbine,so I need to make mine more accurate than it is so I can transition my children into larger rifles.
 
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Just another 22 shooter said:
A bit of thread drift:
So, is my Inland 1943 that has no bayonet lug and the flip sight more desirable to collectors?
Click to expand...

The short answer seems to be "Yes."
Everyone seems to want an 'as issued during the war' version, and assume that the no lug with flip sight is the answer. I cannot really fully agree with that, but the majority of wartime issues were that way.
That configuration is so popular that many people convert them back to that configuration in an effort to get more money for them. The simple truth seems to be that there are more re-converted ones out there than there are original issue ones. Simply put, how would one really be able to tell if the SN dates to the proper time period. I think most would agree that the majority of M1 carbines went through the upgrade to the new sights and bayonet lug. I have seen one in the last five years that I would be comfortable saying was made in the old configuration. It was at the auction of a 90+ year old veteran estate and came in the box that he shipped it home in (to the address of the auction) during 1944. It went for a high price, and I sure hope the buyer kept the box.
I am NOT saying they are all faked, but I am skeptical of many that I see. Uncle Sam did not give a hoot about originality or collectible status. Just the opposite. When orders came to do the upgrades, the upgrades were done at every opportunity. If one finds a M1 carbine in original configuration with arsenal rebuild marks be very suspicious.
There have been books written on the M1 carbine, many agree on many things, and if you're interested in them, the time spent reading them is well spent.
 
lrrifleman said:
With the windage cranked completely to the right, at 25-30 yards the bullet still prints about a foot to the left of the target. Confirmed by at least three other competent riflemen.
Click to expand...

A replacement flip sight won't fix that problem.

Have you checked to see if the barrel to receiver index marks line up?
 
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