|Marlin 70-60 Conversion
|Page 1 of 1|
|Author:||ugean [ Mon Sep 12, 2016 1:46 pm ]|
|Post subject:||Marlin 70-60 Conversion|
I'll start off by answering the question everyone is asking. Why? Well because I had an old model 70 receiver kicking around and a bunch of misfit model 60 parts. Plus I like that the 70 has the shorter barrel. Plus here in NYS you can't have a 70 with a tactical stock and be S.A.F.E. Act compliant. So by doing this conversion I now have a 60 with the shortest legal barrel, shortest legal overall length, in a tactical stock. And boy let me tell you it is so nice to carry through the woods!
So here is how I did it. I started with an old 70 receiver. But the receiver takes the new style lower assembly. I had an old lower assembly, with a broken feeder throat, from my 72 model 60. So I started by replacing the feeder throat. I picked one up on Ebay used. I wanted an older one because they're made out of metal. I should also add that I didn't want a last shot hold open on this gun for personal reasons. I just don't like how on the 60 when you release it, it doesn't feed in the next round. You still have to charge it.
Now the feeder throat I got was a different style with a feed ramp built in. The lifter spring was meant to go along the side, instead of on the top. So when I reassembled it I tweaked the 72 spring and put it along the side. I found out later this didn't work so well, and kept jamming. So I took it apart again and replaced it with a 2014 spring and put it on the top where it belongs. I bent the 72 spring back, put it in the 2014 and both guns are now working fine. See my prior blog post "Marlin 60 lower assembly" for resources on taking the lower assembly apart.
Then I needed to fit the lower assembly to the receiver. Well the 72 was the old style that takes screws in the front instead of sliding under the pins. So I took a grinder to it and matched it to the 2014 side plates that I have. I also only had a spare old style rear pin. Which, come to find out is about 1/16" (maybe it was 1/32") larger than the new style. So I had to drill out the receiver. I'm going to skip over all the playing around I had to do with the lifter spring as that was due to the mishmash of parts I chose to use.
Now it was time to fit it with a magazine tube. I picked one up again on Ebay. I have to say those things are a bit over priced if you ask me. I picked up an old style for the 18 rounds hoping that when I cut it down I would be able to hold more than the modern 14 rounds. Unfortunately, that didn't work out. It still only holds 14 rounds in the tube. Not that, that is so bad as all of my speed loaders are built for 14 rounds. If you play around with the plunger you might be able to get another round in there.
To hold it in place I used an old style front mount that doubles as a magazine mount.
I then measured, marked and cut the outer tube. I then put the outer tube in place so that I could mark the inner tube to the perfect length. Then I took apart the inner tube. A word of advise for making that easier. Take a small chunk of scrap wood and drill a small hole in it. Then line up the little pin with the hole and knock it out into the hole. That way the tube is supported but you're not knocking the pin into the bench below. I used a finishing nail to push the pin out. Be careful they're soft and you don't want to damage it. That pin is also what locks the tube into the outer magazine tube. Next I marked the inner tube accounting for the knob at the end. It is better to cut it a little long and then shave/grind it down until it lines up. I removed the outer tube and used a Dremel tool to cut a slot for the pin to lock into. I cut it just a little too small and used a tiny file to clean it up and make the horizontal cut. A little at a time and now it locks in nice and tight. The magazine spring measured one pound with the plunger pushed in. So I put the spring back in until I had one pound of pressure and cut of the access.
Then I wanted to give it a more modern look. So I ground off the top sight post, and knocked out the rear sight. I used some JB weld to fill in the rear sight and rounded off the front sight (still needs a little finishing work I know). The bluing was getting thin on the receiver and the outer tube was pretty pitted up. So I sanded it all down and hit it with a coat of spray on bed-liner. That gave it that modern day rough look and sealed the gun up nice.
Lastly I put in an old bolt, charging handle, and spring I had kicking around. I made sure everything moved nice and smooth and it was off to the range I went. Like I said before I did have to make some tweaks to the lifter spring later. I put a pic rail adapter on it, a red dot and of course put it in a HT60 (prototype) stock. Let me tell you...This is one fun little gun!!!
Once I get a production HT60 in a couple of months I'm going to put a folding stock adapter on it with a single point sling and this is going to be the best Raccoon gun ever!