Badger Arms
Member
I’ve owned many an Ithaca 37 over the years. Well, recently I happened upon an unconverted (I think) Ithaca 37 made in 1975. About 30,000 of these guns were made and problems were encountered, so Ithaca quietly switched back and offered to retrofit guns made during this series (all with a 381- prefix). Why? I don’t know. I’ve got a 4xxx range Ithaca that I took apart to compare to my 381-series gun. I’ll post some comparison pictures for you to examine.
First some history. John Browning designed the Remington model 17 with a little help from John Pedersen and others at Remington. When he designed it, the disconnector functioned by interaction between the slide stop and a lug projecting from the hammer. Thus, when the slide goes fully forward with the trigger to the rear, the disconnector releases the hammer and “slam-fires” the gun. This is all detailed in Browning’s Patent # 1,143,170. Shortly after its introduction, Remington ‘fixed’ the slam-fire issue incorporating a disconnector that functioned from the trigger as in the Remington Model 8 and AK-47. It hooked the hammer from the rear and required the release of the trigger to fire subsequent shots.
But strangely, Ithaca stuck with the original patent and used a pure Browning style disconnector when they copied the Model 17. Even more strange, some Ithaca’s have no disconnector hook on the hammer and therefore no disconnector function. Holding the trigger back results in a malfunction with a hammer down on a live cartridge. But, that’s not what the 381-series Ithaca 37 is all about. My 381-series gun has a disconnector lug.
The 381- modification has to do with the action bar and left cartridge stop. What was the problem? The left cartridge stop operates by a cam slot on the bolt carrier. When the bolt carrier is nearing the rear of its travel, this cam slot moves the front of the cartridge stop out of the path of the cartridge in the magazine, releasing it into the action. Problem is that this cam is about 4” away from the face of the cartridge stop. Ithaca must have had problems with this arrangement so they opted for something a little more positive. If you’re looking for a similar system, Mossberg uses a front-mounted cam on their shell stops which are situated similarly to the Ithaca 37.
As you can see in the pictures, they put two notches in the action bar with cam slots in them. They extended the top of the cartridge stop up so that the cam in the slide would engage this projection at the front and positively eject the shell in the magazine. The second notch, adjacent to the hole at the rear of the slide bar, is a relief to allow the shell stop to move out of the way when one inserts shells into the magazine.
Minor changes to the left shell stop included a bump behind the face, a redesigned pivot hole, and a hole where the cartridge stop spring goes. Also, the rear cam was moved forward and, though it seems like it was redundant at this point, reshaped. The right cartridge stop also received some attention getting the same pressed “bump” as the left stop.
Whatever the problems, and I don’t know, Ithaca reversed their decision, probably at considerable expense, and resumed production based on the older design. Following this “New Coke-like” fiasco, Ithaca did manage to make one improvement to the Model 37. They deleted the left shell stop pivot screw and replaced it with a simple bent pin retained by the front edge of the trigger plate.
All things considered, the 381-series looks like it should work… don’t know why it didn’t. If anybody has a factory retrofitted gun or perhaps some unknown variation, please post a description ad pictures. Thanks for looking.
First some history. John Browning designed the Remington model 17 with a little help from John Pedersen and others at Remington. When he designed it, the disconnector functioned by interaction between the slide stop and a lug projecting from the hammer. Thus, when the slide goes fully forward with the trigger to the rear, the disconnector releases the hammer and “slam-fires” the gun. This is all detailed in Browning’s Patent # 1,143,170. Shortly after its introduction, Remington ‘fixed’ the slam-fire issue incorporating a disconnector that functioned from the trigger as in the Remington Model 8 and AK-47. It hooked the hammer from the rear and required the release of the trigger to fire subsequent shots.
But strangely, Ithaca stuck with the original patent and used a pure Browning style disconnector when they copied the Model 17. Even more strange, some Ithaca’s have no disconnector hook on the hammer and therefore no disconnector function. Holding the trigger back results in a malfunction with a hammer down on a live cartridge. But, that’s not what the 381-series Ithaca 37 is all about. My 381-series gun has a disconnector lug.
The 381- modification has to do with the action bar and left cartridge stop. What was the problem? The left cartridge stop operates by a cam slot on the bolt carrier. When the bolt carrier is nearing the rear of its travel, this cam slot moves the front of the cartridge stop out of the path of the cartridge in the magazine, releasing it into the action. Problem is that this cam is about 4” away from the face of the cartridge stop. Ithaca must have had problems with this arrangement so they opted for something a little more positive. If you’re looking for a similar system, Mossberg uses a front-mounted cam on their shell stops which are situated similarly to the Ithaca 37.
As you can see in the pictures, they put two notches in the action bar with cam slots in them. They extended the top of the cartridge stop up so that the cam in the slide would engage this projection at the front and positively eject the shell in the magazine. The second notch, adjacent to the hole at the rear of the slide bar, is a relief to allow the shell stop to move out of the way when one inserts shells into the magazine.
Minor changes to the left shell stop included a bump behind the face, a redesigned pivot hole, and a hole where the cartridge stop spring goes. Also, the rear cam was moved forward and, though it seems like it was redundant at this point, reshaped. The right cartridge stop also received some attention getting the same pressed “bump” as the left stop.
Whatever the problems, and I don’t know, Ithaca reversed their decision, probably at considerable expense, and resumed production based on the older design. Following this “New Coke-like” fiasco, Ithaca did manage to make one improvement to the Model 37. They deleted the left shell stop pivot screw and replaced it with a simple bent pin retained by the front edge of the trigger plate.
All things considered, the 381-series looks like it should work… don’t know why it didn’t. If anybody has a factory retrofitted gun or perhaps some unknown variation, please post a description ad pictures. Thanks for looking.
