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SA-20 +3 Magazine Extension Installation

Bobster

.30-06
Picked up a Choate +3 magazine extension for my SA-20 Turkey Thug this week. Got it online directly from Choate. Part number 02-04-43. Cost just under $60 including shipping. They shipped quickly via UPS but failed to provide a tracking number so UPS left me a yellow notice one day but I got it the next--NBD...

Kit is similar to a kit I installed in a Remmy Wingster although this kit required more mods to the tube than the Remmy. Includes mag extension, follower, longer spring and tube clamp as shown.

First step with an unloaded gun is to remove the magazine tube cap, foreend and barrel. Pic shows the tube with round limiting "dowel" removed. There is an "oval" metal backer behind the spring cup that is held in place by a lip at the end of the mag tube. To get the backer out the spring cup is pressed in with the larger screwdriver and backer manipulated out with the small screw driver.
 

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SA-20 +3 Magazine Extension Installation, Part 2

The magazine lip will need to be removed (1) to get the OEM spring cup, spring and follower out and (2) to allow shells to pass through it. The "trick" I used was to send a straight 1/16" welding rod through the cup, spring, then the follower. Looped the rod through a small washer and twisted the end around so it wouldn't snag on the spring. Then the rod was pulled towards the follower until the spring was compressed about 3" and bent about 90^ to hold the spring under tension. Note that the OEM follower has a hole in it while the Choate does not. Also note the "oval" backing washer in the last pic.
 

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SA-20 +3 Magazine Extension Installation, Part 3

To remove the lip, I used a handheld deburr tool as shown. You could use a Dremel or similar if you wanted. I stuffed a rolled up napkin in the tube to keep shavings out. It took a little work because there was a lot of metal to remove but the results were good. Took a smooth file and cleaned up any sharp edges, wiped with alcohol then straightened the rod and allowed the OEM parts to come on out. These parts should be kept because they allow the gun to be reassembled with the extended tube off and OEM parts and ammo limiting dowel in for hunting. The spring cup was used with the Choate tube.
 

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SA-20 +3 Magazine Extension Installation, Part 4

After lightly lubing inside the tubes with some silicone spray, I started reassembling the gun. First thing to note is that now is the time to clean and lube the gun if needed while it is apart. Great care must be taken to get the longer spring into the old mag tube and extended tube so (1) it doesn't fly out and (2) it doesn't get damaged. Be careful not to cross-thread the extension onto the mag tube.

Once the tube is screwed on, attach the barrel clamp in a suitable location. I chose about 2" from the muzzle. The smaller of the ends goes around the barrel. Even if the sling mount is not being used, it makes a good "T" handle for tightening.

Since I probably won't be hunting turkeys anytime soon, I just call this gun "The Thug". Loaded 7 into the mag and 1 in the chamber, then cycled the bolt quickly and there was no FTF or FTE. I'll update with a range eval in the future the next time we go to the range.

Also shown is The Thug's most adequate ghlowstring sights (glow and ghostring combined). Note how the rail is "cupped" to allow viewing the sights.

PS: aside from an non-existent pistol-grip stock, I'd like to get a breacher extended choke one of these days. Last I looked they were about $50.

I also have a Tasco ProPoint I can put on it for low-light conditions...

I might make a zombie bayonette for it... :twisted: I'll detail this in a separate post...
 

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What is the length of the barrel? I have the 20" tactical and the 7 shot Choate (7+1) barely fits to the end of the barrel (about 1.5" less). I used the factory follower because with the Choate I could only load 6 in the mag tube.
I added an extended choke because I was shooting trap and not doing well.
Mine also has very high sights like an AR and they are not so good for trap or skeet.
Is yours specifically a turkey barrel and if so, what else is different?
 
BrianJ said:
What is the length of the barrel? I have the 20" tactical and the 7 shot Choate (7+1) barely fits to the end of the barrel (about 1.5" less). I used the factory follower because with the Choate I could only load 6 in the mag tube.
I added an extended choke because I was shooting trap and not doing well.
Mine also has very high sights like an AR and they are not so good for trap or skeet.
Is yours specifically a turkey barrel and if so, what else is different?

The Thug has a 22" ribbed barrel. It has a flush skeet choke in it--I removed the ultra-tight, extended, ported turkey choke it came with so I wouldn't damage it with steel shot and more importantly, so I could shoot slugs out of it. I guess you could call it a "turkey" barrel if you include the installed sights.

There is a reason you could only fit 6 in the tube because that is what the +2 is supposed to increase capacity to. Stock, the SA-20 holds four in the tube and one in the chamber: 4+1=5 rounds total. So when Choate says "+2 for a 7 round capacity", they are including the round in the chamber. Their follower is designed to prevent crushing or distortion of the spring by limiting compression. I would suggest putting the Choate follower back in so you don't damage the spring.

The factory limiter takes the place of 2 rounds for hunting, leaving a total of 3 (2+1), the legal limit in many states.

Another thing that can damage the Choate spring is if the gun is kept fully loaded all the time--they suggest buying a replacement spring to alternate every so often.
 
You are correct. The Choate extension I got is only a +2, but, from the factory my gun could put 5 in the mag +1 in the chamber. The +3 would have been longer than my barrel and now, apparently illegal in NY. Maximum of 7 in the tube by law.

I called Choate when I installed it because it only allowed me to load +1. I actually got to speak to the boss without even realizing it. The sales lady first explained that they included the one in the chamber in the count and that a lot of people felt deceived but that is the way it was worded on the web site (kind of fine print I guess). I guess the boss (can't remember his name) knew about the complaints and corrected what she had told me and said that it should add 2 to whatever my previous max was. He suggested using the factory follower and also to trim the spring 1/2 coil at a time just until I could fit the 7 in the tube. It worked. It easily loads 7 of the 2 3/4 " shells but only 6 with 3 ". Never keep it fully loaded anyway but I will get a spare spring.

I will try putting the Choate follower in and see if it still works. Someone mentioned a teflon coated follower was available but I haven't seen it.

I never heard of the 22" barrel. That sounds like a good size. I am trying to find one of the 26" barrels but no luck and I'm not holding my breath. I had the choke added to mine because I was shooting trap for practice. Now I enjoy it. The RO at the range keeps asking me when I am going to get a "real" trap gun. As long as I keep hitting better I will stay with it.

The chokes I bought are the Trulock extended and they are rated for steel shot. The machine shops I contacted could only thread for Win/Mossberg chokes but the 26" SA-20 barrel comes with Benelli threaded chokes so I can't swap them anyway. I only use slugs with the Improved Cylinder choke.

Waiting for the snow to start melting to get back to the range.

Thanks for the help.
 
Actually tried it last night. With the Choate follower the 7th round only goes in about half way. I do see what you mean though. the Choate has a "tail" that would stabilize the spring when compressing.
 
BrianJ said:
Actually tried it last night. With the Choate follower the 7th round only goes in about half way. I do see what you mean though. the Choate has a "tail" that would stabilize the spring when compressing.

Now you have me wondering about actual capacity while Mossy literature says "5 round capacity" in some locations it says "5+1". :?: I can't remember if I've tried loading 5 in the tube (before extension) or not... :?

I did notice the "halfway" issue with the "last" round, in fact, the round got slightly jammed against the elevator but I was able to pry it out without much effort... :x This bothered me not because I couldn't fit another round but because in the heat of reloading, one could lose track of rounds then end up with a jammed round halfway in.

I'm going to re-check capacity the next time I have the gun out. Maybe I'll modify the Choate follower by nipping off a 1/2" or so... We might even go shooting today... :D
 
I'd need a snorkel parka and x-country skis to go today. More snow on tap for tonight.
Have fun and be safe.
 
BrianJ said:
I'd need a snorkel parka and x-country skis to go today. More snow on tap for tonight.
Have fun and be safe.

I wonder if they shovel at Calverton? :lol:
 
You are correct, Brian, regarding capacity of the SA-20. I stand corrected. Read on...

Since you had me wondering about capacity, I re-installed my OEM spring, cup, follower and magtube cap. This wasn't hard at all, the only real difference being that the spring and follower are no longer held captive by the crimp so technically there would be more parts to lose in the field or fall into a pile of sand (or snow! ;-)). The OEM spring compresses easily.

I then proceeded to load FIVE 2-3/4" rounds in the tube and ONE in the chamber for a total of 5+1. Function tested ejection and all rounds came out fine. I also loaded FOUR 3" rounds and ONE in the chamber for 4+1. Also functioned tested ejection successfully.

Although I didn't install it to check, the hunting limiter rod takes the place of THREE 2-3/4" rounds in the tube as it should, leaving 2+1. I would imagine it is the same for 3" but I didn't check.

Re-installed the +3 extension kit with included parts and re-checked capacity and much to my chagrin, as noted before, I could only insert 7 rounds, plus 1 of 2-3/4" and 6 rounds, plus 1 of 3". The 3" rounds made the spring/and or follower stick in the tube and the rounds just bounced around and I had to take it apart to get the spring/follower unjammed and rounds out.

So I tried the OEM follower with the 2-3/4" rounds and could still only insert 7 rounds. It would appear that the spring must be "stacking up" and probably needs to be shortened. The OEM spring is 18-5/8" long and 5/8" in diameter. The Choate spring is 29-1/4" long and 3/4" in diameter. The OEM follower has a ridge inside that the Choate spring stops against while the OEM spring goes all the way in, a difference of about 1/4" depth.

The Choate follower is about the size of 1 round while the Choate tube is about the size of 3 rounds. The follower is also marked "REM 20ga" while the tube has no markings at all. BTW, the tube is shinier than the matte-black barrel of The Thug, not that it is very noticeable.

When I get a chance, I am going to call Choate and see what's up. I never did get to go shooting--wish I had more time...
 
Forgot to post these--new forum SW won't let me edit... :rolleyes: (UPDATE: I found the "Edit" link... doh!)
 

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I read in a post here a while ago, before I did mine, that I had to trim the spring. I was afraid to cut it until I knew I could get a new spring from Choate.

I started taking off 1 coil at a time then when I thought I was close, 1/2 coil at a time. stopped when the 7th round fit in. probably took 4-5 inches off.

After it settled a while, still kind of hard to load 7 so later I took off another 1/2 coil. then bent back the cut loop a little to make a flat loop to seat in the plastic cup at the end of the tube. hard to get it bent. I'm sure there is a trick to it.
Don't want to take too many coils off or the last round will have no pressure. My last round feels kind of light compared to the others but feeds every time so far.
Check with Choate in case the +3 is different.
Good luck.
 
UPDATE and Range Report! :D

Decided I would try cutting some coils as Brian had to do. No one coil at a time for this boy... ;) I went straight to cutting exactly 2-3/4" off, the length of a round. The cut end of the spring was smoothed on a deburring wheel in my shop. Opted to use the pretty aluminum red anodized factory follower because I felt it would "contain" the cut end of the spring better. Put the gun back together and easily loaded 8 rounds into the mag tube! :p

At this point I realized I had forgotten the plastic "cup" on the muzzle (uncut) end of the spring SO I disassemble and reassemble WITH the cup in place. Tried to load 8 rounds again and they just wouldn't load. I could "feel" the spring winding up so back apart it came, and off came the cup. Back together without the cup and 8 rounds loaded easily (again). They also manually ejected easily which is equally important.

A friendly, concerned reminder that it is important to keep your finger OFF the trigger when cycling the bolt to clear rounds! Bad things can happen if you don't! :eek:

Had a chance to go to the range yesterday and of course, one of the guns in the lineup was the SA-20. :) Loaded 8, racked the bolt to chamber a round then loaded another in the tube for a total of 9 rounds, ready to rock. Burned through the 8+1 in seconds, without one FTF or FTE. Went through a box of 25, 9+9+7, Federal Target Load "blue box", 2-3/4",#8 shot, 7/8oz of shot, 1210fps. I've yet to fire any slugs or buckshot through this, but I would venture a guess it will cycle fine. :)

About the only issue was when loading the tube at about the 6th round. The round would hang going in but a little wiggle and it would continue on. This didn't happen all the time but about half the time, both at the range and in the shop beforehand. When I get a chance, I'll take a moment to check and smooth any sharp edges in the tube and extension. Another issue might be that my thumb is fatter than a 20ga round and it takes a little "squishing" of said thumb to properly push the rounds in until they "click".

Pic1 shows the parts not used. They went into the plastic case the kit came in as well as the OEM endcap, spring and hunting spacer. As mentioned above, these parts should be kept for hunting and a perfect place is the Choate packaging.

Pic2 shows the clamp marked with a mechanical pencil so it can be re-installed in the same location every time. The sling mount is the perfect device to tighten the clamp, even though the sling isn't attached there, nor do I want it there... You can also see the difference between the finishes on the tube and barrel.

Pic3 shows my 13 year old showing me how it's done... :rolleyes: :D This is the plinking range at our club, which allows just about anything including full-auto. The berms are easily 30-40' high. This is a SAFE range. We were shooting at the clays up on the berm.
 

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Nice job. Now you have me thinking. I won't cut the spring any more until I have a backup. I am not that daring.
I put a half dozen 3/4 oz slugs through it at 50 yds on Saturday. Way more accurate than I thought. 4 rounds bullseye in a 3" circle. The other 2 out at about 4-5 in but all in the target.
You're lucky, my daughter wants a shotgun like Kate Middleton shoots. I'm guessing $20,000 or more. No point in doing it halfway I guess. I told her to marry a royal prince and let him get it for her.
 
Brian-
when you took off the O.E.M choke -what did you put in it's place ?

Brian will probably be around to answer soon but I believe he has a Tactical 20" model that came with cylinder bore (no choke) that he had tapped for Remmy chokes (I think...). The Thug (22") takes Benelli/Beretta chokes.
 
Thank u Bobster ; I remember a thread about these very facts .........but am too lazy to search . It's just too easy to ask you fellers !!
I just want a nice choke that can shoot buckshot and slugs for those pesky Zombiee Turkeys .
 
I just want a nice choke that can shoot buckshot and slugs for those pesky Zombiee Turkeys .

I have a skeet choke in the Thug. Came with a ported turkey choke I'm saving for when and if I ever go turkey hunting with it...
 
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