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Choate Tool Mossberg Magazine Extension
As Low As $59.99 Save Up to 12%
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Most Helpful Negative Review It works but not with new follower.
Can’t fit a 7th shell in if you use the provided follower. Use the original one and you can barely get a seventh shell in but it works. Goes past a 18.5 inch barrel by about one inch. Since optics planet won’t let you post a review without there being 200 characters here’s a useless sentence �
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works good

by ben, Verified Owner from CA, United States Written on April 5, 2026
Good for an 18” 990 aftershock. Ended up 1/4” shy of the barrel and added +1 capacity. Quality is great and the price is reasonable
Would recommend: Yes
Was it helpful to you? Yes | No

Not a correct fit.

by Eric, Verified Owner from CO, United States Written on March 3, 2026
The threads on the extension did not grab on and the extension flew off under recoil causing my gun to disassemble itself at the range. Not worth having 1 more shell but sacrificing reliability.
Would recommend: No
Was it helpful to you? Yes | No

Perfect upgrade to the Mossberg 590S

by Xyphon, Verified Owner from IA, United States Written on January 9, 2026
Perfect upgrade to add +1 capacity to the magazine tube. Fits the 590S perfectly and is very easy to install. Personally I still only load at the original capacity. Saves the spring and gives me options if I need it.
Would recommend: Yes
Was it helpful to you? Yes | No

Mossberg 590 + 1 tube extension

by Mossberg plus 1 extension, Verified Owner from CA, United States Written on May 12, 2024
Solid quality. The plus 1 cap is indexed (on the bottom) like the original 590 cap so when you screw the cap onto the tube the cap locks solid and tight on the tube with the detent ball on the barrel (magazine) lug. Can’t go wrong with the pricing either. Optics planet has the best pricing out there. �
Pros:
  • You get an extra round. It fits just like the mossberg extension.
  • Fits just like extension from mossberg
Cons:
  • None
Best Used for:
  • Defensive shotguns
  • Defensive shotgun
Would recommend: Yes
Was it helpful to you? Yes | No

Perfect length

by Denny, from PA, United States Written on February 14, 2024
Bought this to bring the magazine even with the 18" barrel on my 835. Absolutely perfect!
Would recommend: Yes
Was it helpful to you? Yes | No

Poorly manufactured

by JT, from MD, United States Written on December 14, 2022
I bought extension directly from Choate. It was made crooked. Not cross threaded but actually crooked. It looked like a hot dog hanging off the end of the mag. So I bought another from Optics Planet. It was the same way. Optics Planet was great about returning it. Fast too. Never heard from Choate. Long history with Choate products. Never again.
Would recommend: No
1 of 1 found the following review helpful.
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