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A couple of folks asked what the differences are between the WWII M1 Carbine and the later copies that came out. So I did a comparison of what I have. A 1944 Underwood and a 1970's Universal. Universal made several changes to the design and all were bad. They use the same mags, the Universal has no bayo lug.
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The Slide was redesigned to have a cut in it where the bolt lug can show thru. Very stupid, it just makes it easier for dirt to get into the action. The cut was also a weak place in the slide and many have cracked and broken and there are no spare parts to be found.
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A view of the twin springs of the Universal, I guess they thought more was better. It's not, it adds parts to break and is a ***** to take apart and reassemble until you do it a few dozen times.
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The WWII Carbine has one spring and it easily pops out and back in. The Universal has to have a cross oin removed that allows the two long rods to move back into the mag well thus allowing the springs to be removed. Now imagine putting them back in... you have to hold the rods forward, with a compressed spring around them while sliding the cross pin back into place. Real smart... try that in a muddy field in the cold rain.
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The trigger group slides off toward the rear.
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The trigger groups are very similar. That hammer spring is a serious ***** to get out and back in. This is the one place an improvement would have helped but they didn't change anything.
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Major components.
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The different gas block and piston designs. The Universal uses a pin to keep the piston in place, the WWII used a treaded nut. You can see the powder residue that leaks around the Universal piston. You can also see the pin at the back of the receiver that can be pushed in and acts as a "bolt hold open". The WWII models just used a catch on the charging handle part of the slide.
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The far end of the gas blocks.
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The same bolt tool works on both bolts... and YES, you want to own a bolt tool. Hours of swearing and crawling around on your hands and knees looking for the springs and bits can be avoided for $29.95. Ask me how I know.
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The bolt redesign on the Universal includes a spring around the firing pin, I guess to stop an AD if the gun was dropped muzzle down. The tang on the WWII firing pin, when installed in the receiver, rides on a ledge that prevents the firing pin from moving forward unless the bolt is rotated at least 50% into battery. The Universal depends on a ledge on the back of the bolt to prevent the hammer from reaching the back of the firing pin unless the bolt is rotated. Both bolts have this ledge. I was unable to mke either gun pop a cap unless the bolts were at least 50% rotated.
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Closer look at the pin used for holding the bolt open.
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Closer look at the pistons.
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Receiver markings, rear sights, scope mount holes in the Universal.
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Side by side.
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The Slide was redesigned to have a cut in it where the bolt lug can show thru. Very stupid, it just makes it easier for dirt to get into the action. The cut was also a weak place in the slide and many have cracked and broken and there are no spare parts to be found.
A view of the twin springs of the Universal, I guess they thought more was better. It's not, it adds parts to break and is a ***** to take apart and reassemble until you do it a few dozen times.
The WWII Carbine has one spring and it easily pops out and back in. The Universal has to have a cross oin removed that allows the two long rods to move back into the mag well thus allowing the springs to be removed. Now imagine putting them back in... you have to hold the rods forward, with a compressed spring around them while sliding the cross pin back into place. Real smart... try that in a muddy field in the cold rain.
The trigger group slides off toward the rear.
The trigger groups are very similar. That hammer spring is a serious ***** to get out and back in. This is the one place an improvement would have helped but they didn't change anything.
Major components.
The different gas block and piston designs. The Universal uses a pin to keep the piston in place, the WWII used a treaded nut. You can see the powder residue that leaks around the Universal piston. You can also see the pin at the back of the receiver that can be pushed in and acts as a "bolt hold open". The WWII models just used a catch on the charging handle part of the slide.
The far end of the gas blocks.
The same bolt tool works on both bolts... and YES, you want to own a bolt tool. Hours of swearing and crawling around on your hands and knees looking for the springs and bits can be avoided for $29.95. Ask me how I know.
The bolt redesign on the Universal includes a spring around the firing pin, I guess to stop an AD if the gun was dropped muzzle down. The tang on the WWII firing pin, when installed in the receiver, rides on a ledge that prevents the firing pin from moving forward unless the bolt is rotated at least 50% into battery. The Universal depends on a ledge on the back of the bolt to prevent the hammer from reaching the back of the firing pin unless the bolt is rotated. Both bolts have this ledge. I was unable to mke either gun pop a cap unless the bolts were at least 50% rotated.
Closer look at the pin used for holding the bolt open.
Closer look at the pistons.
Receiver markings, rear sights, scope mount holes in the Universal.
Side by side.
