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SA-20 +3 Magazine Extension Installation

I would not say that about me--YOU have plenty more rounds through yours than I do... ;) Besides, I define an "expert" as in "ex" is a has-been and "spert" is a drip under pressure... :D

Welcome aboard, Zeke! :)
I have a "slight" problem during the install of my sa-20 ext. tube. Is there a way to converse with you?
 
I have a "slight" problem during the install of my sa-20 ext. tube. Is there a way to converse with you?

I keep crazy hours and only pop on here once or twice a day. Any questions may be answered if you reread this thread from the beginning. In a nutshell, I shortened the mag spring and re-used the OEM follower. You can pose your question here and see if I or someone else can answer it for you.
 
I keep crazy hours and only pop on here once or twice a day. Any questions may be answered if you reread this thread from the beginning. In a nutshell, I shortened the mag spring and re-used the OEM follower. You can pose your question here and see if I or someone else can answer it for you.
Thanks! Is it possible to heat up the magazine tube to remove it?
 
Thanks! Is it possible to heat up the magazine tube to remove it?

Probably, but I've never done an SA-20. I'd remove the barrel, disassemble receiver and use a heat gun in the tube area and be patient. You are only trying to soften the Loctite so you can twist the barrel out. Be mindful of how you clamp it so you don't mar or crush it. Why do you want to remove the tube, anyway?
 
Pops is a machinist and wanted to remove the lip at the end using a a metal lathe but after reading this thread we'll probably use a demurring tool like you demonstrated.
 
I just used a screwdriver to hold the follower in a few inches and used a small hacksaw and slowly cut the end of the mag tube off. When I was halfway through cutting I removed the screwdriver and continued cutting until through, the plastic cap came right out. Cleaned it up with some 220 sandpaper and installed the mag extension, the extension makes the shotgun look much better. I left the plastic cap out when reassembling it back together. I'm going to the range tomorrow for a function check, this is a brand new gun never fired so hopefully all goes well and see how many shells I can get in the tube.
 
Hello guys. I went low tech. I’m paranoid of a Dremel running away on me. I used a rat-tail and a finer half-round file (painstakingly) after I removed the spring and follower. I finished with the Dremel to smooth and polish the tube.
I use a Choate machine +2 and a +4 with no issues (different springs).
Just make sure the extension threads all the way in until the inner tubes touch square and smoothly. If there is a gap or a lip, the rim of the shells will hang up in it. Test it a few times with no spring and just tilt the gun and let the shells slide back and forth all around.
Good luck and be safe.
 
I forgot to add, I taped up the ends of the files to not scratch the tube. I also put a rag down the tube to catch filings.
 
My machinist Pops won out and we removed the magazine tube with a heat gun. We put it on his lathe to remove the lip.
 

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Excellent. Looks good. Right tool for the right job.
I do have one question, is that lathe in your basement or in a shop.
I’m jealous.
 
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Excellent. Looks good. Right tool for the right job.
I do have one question, is that lathe in your basement or in a shop.
I’m jealous.
Sorry for not seeing this until now Brian. Dad’s basement. 87 and he’s still fabricating for fun after 44 years in a mill here in Eastern Ohio.


Sent from my iPhone using Tapatalk
 
87 and he’s still fabricating for fun after 44 years in a mill here in Eastern Ohio.

Nice of you to humor the old guy... :D But seriously, keeping active keeps the mind sharp... :)

But when Alz sets in, not much you can let them do unless you're willing to "babysit" and be willing to argue with someone who has forgotten what they are arguing about... :(
 
I thought I’d add my experience to the mix; I have the Tactical SA-20, like BrianJ, and just added the Choate +2 extension. I too could only load +1, meaning 6 in the tube; the seventh shell only went halfway in. My Choate kit did not come with a follower, so I’m using the factory one.

I read in this thread that Choate recommended cutting 1/2 coils off till it will take the 2 shells, but I thought I’d first try the stock spring, which when in place is longer than the barrel. I put it all together and BOOM- it takes 7 shells and seems to have good tension and push all the shells out just fine. I’m going to continue testing this to see if using the factory spring is a viable option, and leave the mag type filled to see if time weakens the push of the spring.
 
So, after over a week of sitting with seven shells in the extended (7+1) Choate tube with the shorter factory spring inside, I emptied it out to see how the spring felt. It was very weak, with light pinkie pressure needed to push the follower down, which I felt unacceptable.

I ordered a second Choate spring, which arrived today, to experiment with. Again, with it in place, the tube took 6 1/2 shells. I started big, cutting 2 1/2 inches off, testing it, then taking 1 inch at a time. It took removing 7 1/2 inches off the spring before I could get the tube to take seven shells. I also had to remove the black plastic reverse follower that was hidden in the extension. The spring is still longer than the factory spring and, when empty still has decent pressure.

The Choate tube is about an inch shorter than the SA-20 Tactical barrel. I wish they made the tube longer, close to even with the barrel above it; it would have given the spring a bit more room when compressed. I’m sure they had their reasons…
 
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