Why does a Gill-gun (6A/87A) have gills? Here is why.

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Catt57

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Here is the answer. This is a selected section of the actual patent explaining the function of the gills.

When no specific means are provided for the escape of this blast of gas, the fouling, that is to say, the mixture of bullet grease and powder residue is forcibly blown back into the various parts of the action adjoining, and to the rear. The accumulation of this fouling in the parts of'the action will, in a relatively short time, cause the various parts to stick and fail to function properly,
In a gun of this type, that is to.say, a semiautomatic or automatic blow-back gun, this condition renders the gun inoperative, or at least unreliable. It is, therefore, advisable to provide as generous a means of escape for the gas and the fouling carried thereby as possible.

I have accomplished this by making the opening on the left-hand side consist of a series of substantially vertical slots, having such a width in relation to the thickness of the wall of the receiver that no gas or particles of fouling can be directed to the rear at an angle of less than about 45 degrees with the axis of the gun, which gun axis is the basis of all the angles herein mentioned. This permits the necessary escape of the fouling without the possibility of any of it .being directed back into the shooters face.



Here is a link to the full patent documents on Google patents.

https://patents.google.com/patent/US2290156A/en?oq=Us2,290,156
original.png



This includes Savage models 6 and 7, Stevens/ Springfield models 85 and 87, and various other store brands.
 
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Catt57

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I still need to get ours running. Ejects the fired round but the cartridge lifter nearly bends the next round in half.

Could be lifter alignment. With the bolt open, the top of the lifter should be nearly even with the feed lips or maybe just very barely above them.
Also make sure the lifter spring isn't installed backwards. It's quite a common occurrence as it can be a pita to install it the correct way.
 

1mathom1

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Could be lifter alignment. With the bolt open, the top of the lifter should be nearly even with the feed lips or maybe just very barely above them.
Also make sure the lifter spring isn't installed backwards. It's quite a common occurrence as it can be a pita to install it the correct way.
I'll check. Thanks.
 

D V US

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My first rifle at age 13 was a Stevens click-clack with a beautifully figured wood grain... nylon stock. I loved the thing and plumb wore it out. The "gills" may have let SOME of the crud escape, but definately not all. They DID let in everything when you carried it in the woods, leaves, twigs, dirt, bugs and whatever else was on the landscape small enough to fit. But for plinking in the back 40 it was great. I need to find another one just for old times sake.
 

Catt57

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My first rifle at age 13 was a Stevens click-clack with a beautifully figured wood grain... nylon stock. I loved the thing and plumb wore it out. The "gills" may have let SOME of the crud escape, but definately not all. They DID let in everything when you carried it in the woods, leaves, twigs, dirt, bugs and whatever else was on the landscape small enough to fit. But for plinking in the back 40 it was great. I need to find another one just for old times sake.

That would have been the Tenite stock. Those are a bit harder to come by but not impossible. Most of the ones I've seen have been a Sears branded 87A. (Also known as the 87T, for Tenite. )
 

1mathom1

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If you ever make it to OKC, bring it with you and I can take a quick look at it.
Thanks. I appreciate that. It's been in the family for as long as I can remember and I'm 63. My older brother is 71 and it's been around as long as he can remember, too. The malfunction has always been present so when we shot it we pushed the bolt handle in and used it as a repeater. I'll give you a shout one of these days.
 

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