Winchester 1897 6 round conversion

Open forum for shotguns.
User avatar
Fyodor
Founding Member & Supporter
Founding Member & Supporter
Posts: 1512
Joined: 04 Jan 2014 05:45
My Press Choice: Progressive
Location: Gernsbach, Germany
Has thanked: 794 times
Been thanked: 504 times

Winchester 1897 6 round conversion

Post by Fyodor »

Hi there!

I got a Chinese Norinco copy of a Winchester 1897 pump action shotgun. I'm using it in WildBunch matches. Often we are allowed to load the first six rounds off the timer, every reload afterwards is on timer.

The ammo I use is fairly long because of it's roll crimp. It falls perfectly from my side by side guns, and because of its extra length it feeds flawlessly in the pump action. I've tried shorter ammo, which sometimes binds at the chamber, causing me to accidently double feed the gun. The downside is, the magazine only accepts 5 and a half rounds of this ammo.

So I bought a 6 round conversion, which consist of an aluminium follower and a magazine spring. When taking the gun apart to install it, I found that the previous owner already installed a six round conversion... but at least I got a spare spring to do some experiments: cutting down a few coils and stretch the spring actually brought me to a point where I could load 6 rounds of my ammo, and it would still feed the last one. Once... because after I filled the mag, the spring is compressed back to its original length. No matter how hard I stretch it, it always goes back to its old form.

Is there any trick on stretching coil springs that I'm not aware of? Has anybody succesfully stretched a magazine or other spring permanently? I'm sure I need to over-stretch, so it will only go back that much, but even when stretching the spring to nearly one and a half times its original length, it will compress back to start completely.

After cutting off that many coils, it won't feed the last round any more. Luckily I still have the spring that came with my gun, otherwise I wouldn't have started cutting anything, but I still like to get it working with 6 of my favorite shells.
"I disapprove of what you say, but I will defend to the death your right to say it"
- Evelyn Beatrice Hall, often misattributed to Voltaire

I think I'm thinking, therefore I may possibly be.
User avatar
Ranch Dog
Site Admin
Site Admin
Posts: 6456
Joined: 22 Jun 2013 17:16
My Press Choice: Progressive
Location: Inez, TX
Has thanked: 1616 times
Been thanked: 2850 times

Re: Winchester 1897 6 round conversion

Post by Ranch Dog »

Can't help with the spring but... no pictures?
Michael
Image
User avatar
Fyodor
Founding Member & Supporter
Founding Member & Supporter
Posts: 1512
Joined: 04 Jan 2014 05:45
My Press Choice: Progressive
Location: Gernsbach, Germany
Has thanked: 794 times
Been thanked: 504 times

Re: Winchester 1897 6 round conversion

Post by Fyodor »

I'm in the office, posting here during my lunch brake. I'll try to take few pics this week.
"I disapprove of what you say, but I will defend to the death your right to say it"
- Evelyn Beatrice Hall, often misattributed to Voltaire

I think I'm thinking, therefore I may possibly be.
User avatar
buckeye43210
250 Shots
250 Shots
Posts: 253
Joined: 20 Dec 2014 09:47
My Press Choice: Progressive
Location: TPA
Has thanked: 23 times
Been thanked: 131 times

Re: Winchester 1897 6 round conversion

Post by buckeye43210 »

I'm no metallurgist, but you'll probably want to anneal your spring first, stretch it, then temper it. A fixture or jig to hold the stretched spring while tempering it may be useful.
User avatar
Fyodor
Founding Member & Supporter
Founding Member & Supporter
Posts: 1512
Joined: 04 Jan 2014 05:45
My Press Choice: Progressive
Location: Gernsbach, Germany
Has thanked: 794 times
Been thanked: 504 times

Re: Winchester 1897 6 round conversion

Post by Fyodor »

Springs are heat treated, which I can't copy at home. If you anneal too much they become soft and lose tension, of you quench too much they become brittle and break.

I might try to tension the spring and then shortly heat it up just a bit, that might work. I'll keep watching for a solution, but if none comes up, I'll try that.
"I disapprove of what you say, but I will defend to the death your right to say it"
- Evelyn Beatrice Hall, often misattributed to Voltaire

I think I'm thinking, therefore I may possibly be.
User avatar
buckeye43210
250 Shots
250 Shots
Posts: 253
Joined: 20 Dec 2014 09:47
My Press Choice: Progressive
Location: TPA
Has thanked: 23 times
Been thanked: 131 times

Re: Winchester 1897 6 round conversion

Post by buckeye43210 »

Fyodor wrote:Springs are heat treated, which I can't copy at home. If you anneal too much they become soft and lose tension, of you quench too much they become brittle and break.

I might try to tension the spring and then shortly heat it up just a bit, that might work. I'll keep watching for a solution, but if none comes up, I'll try that.
Yes, some people "rejuvenate" their magazine springs using a jig and an oven.
User avatar
Fyodor
Founding Member & Supporter
Founding Member & Supporter
Posts: 1512
Joined: 04 Jan 2014 05:45
My Press Choice: Progressive
Location: Gernsbach, Germany
Has thanked: 794 times
Been thanked: 504 times

Re: Winchester 1897 6 round conversion

Post by Fyodor »

This is the gun I'm trying to tweak:
DSC_2268_bearbeitet.jpg
It's a Chinese (Norinco) copy of a Winchester 1897 trench gun. The barrel shroud has been removed by its former owner, but I still have one (including an original bayonet). Because the barrel was fittet with a glued in front sight, I can't put it on, though.

Here are the magazine springs I got for this gun:
DSC_2275_bearbeitet.jpg
On top you see the original spring that came with the gun, on the bottom you see the "6rd"-replacement. As you can see the 6rd has a longer lead, and less coils. Thus it should compress to a shorter block length. What you can't see is that it's also a little bit smaller in diameter, so it can sit inside the magazine end cap instead of on top of it as the original spring. That should further enlargen the available space for the cartridges.

Unfortunately still only 5 1/2 shells would fit in the mag, so I started to cut the new spring down bit by bit. Originally the two springs have been of the same length.

I've cut the spring down to a point where I can nearly fit 6 rounds... if I cut another two coils it should work. But then I ran into another problem: the spring got too short to feed the last shell.

This is the original spring protruding from the mag:
DSC_2270_bearbeitet.jpg
This is the cut down, stretched 6rd replacement:
DSC_2272_bearbeitet.jpg
You do not have the required permissions to view the files attached to this post.
"I disapprove of what you say, but I will defend to the death your right to say it"
- Evelyn Beatrice Hall, often misattributed to Voltaire

I think I'm thinking, therefore I may possibly be.
User avatar
Fyodor
Founding Member & Supporter
Founding Member & Supporter
Posts: 1512
Joined: 04 Jan 2014 05:45
My Press Choice: Progressive
Location: Gernsbach, Germany
Has thanked: 794 times
Been thanked: 504 times

Re: Winchester 1897 6 round conversion

Post by Fyodor »

This is the 6rd spring after loading the mag with 6 rounds once:
DSC_2273_bearbeitet.jpg
DSC_2274_bearbeitet.jpg
As you can see, it is compressed to original length, and completely disappears in the magazine tube. The top of the spring is about an inch below the end cap. It still does feed the last round most of the time, but it can bounce back halfway into the mag, blocking the action. It doesn't need a lot of tension to feed the last shell, but the follower should still have a little tension when the mag is empty. This is the case before filling the mag, but not afterwards.

So I need a way to stretch the spring permanently.

I came up with the following idea:
DSC_2276_bearbeitet.jpg
I took an M8 threaded rod, 4 nuts and 4 large diameter washers.
DSC_2280_bearbeitet.jpg
I filed down the washer on one side, and filed in an angled slot for the spring. That way I won't squash or break the spring where it is clamped, and it centeres a bit better on the threaded rod. One end is fixed, while the other can be turned up and down. This is a slow process, because I have to turn the nuts by hand, alternating one turn at a time until I reach the desired length, so the spring won't slip out. Now the spring is stretched to the desired length plus 4 inches. I also bought a cheap hot air gun, because this setup won't fit into my oven. I'll have the spring sitting for a few days, and will treat it with hot air probably today. Then it'll sit stretched for another couple of days, and then I'll see if this worked out.
You do not have the required permissions to view the files attached to this post.
"I disapprove of what you say, but I will defend to the death your right to say it"
- Evelyn Beatrice Hall, often misattributed to Voltaire

I think I'm thinking, therefore I may possibly be.
User avatar
Ranch Dog
Site Admin
Site Admin
Posts: 6456
Joined: 22 Jun 2013 17:16
My Press Choice: Progressive
Location: Inez, TX
Has thanked: 1616 times
Been thanked: 2850 times

Re: Winchester 1897 6 round conversion

Post by Ranch Dog »

I think it will work! Great idea for stretching it! I wonder if you heated the exposed end of the threaded rod with a propane torch if enough heat would transfer down the length of the spring? Probably not due to the length of the rod.

Very nice looking gun!
Michael
Image
User avatar
Fyodor
Founding Member & Supporter
Founding Member & Supporter
Posts: 1512
Joined: 04 Jan 2014 05:45
My Press Choice: Progressive
Location: Gernsbach, Germany
Has thanked: 794 times
Been thanked: 504 times

Re: Winchester 1897 6 round conversion

Post by Fyodor »

No, I'll use the hot air gun to blow from the sides. Close to perfect heat distribution would be achieved if I put the whole seutp into a copper pipe or similar, and heat that from the outside. But that is too bulky and cumbersome for me, so I'll just blow hot air to the spring directly, while rotating the jig. Spring steel is tempered at about 400-600°C, the hot air gun can be set to up to 550°C. So I'll set it close to maximum, and will heat the spring for a while.
"I disapprove of what you say, but I will defend to the death your right to say it"
- Evelyn Beatrice Hall, often misattributed to Voltaire

I think I'm thinking, therefore I may possibly be.
Locked

Return to “Shotgun Discussions”