I followed the written and video directions to the "T." Despite oiling both the tool and the Mag Tube, the tool became horribly stuck in the mag tube. I had to totally disassemble the gun and use a wooden dowel to drive the tool out from the Rear of the gun (stock end).
The dents were not removed as well as shown on the video, in fact, the dents became misshapen and exaggerated on the outside of the mag tube. I had to use a Foredom tool for almost an hour on the inside and outside of the mag tube and then had to re-blue everything. What should have been a 20 minute job, turned into an hour and a half nightmare!!!! The customer's BBL now is difficult to install and remove, but can be done without tools. Next time I will try using a heavy red grease and not a light gun oil!!!!! We'll see....

After reading some of the reviews on this item I have to make some comments and observations. This tool as indicated is a dent remover and is designed to fit the inside of a magazine tube that has a "dent". It should go without being said that any item inserted into any other item that was not originally the maximum outside diameter will stretch that metal beyond specifications. The instructions I received with my tool says to use a brass hammer and lubricant after cleaning the magazine tube inside. I have yet to stick the tool or use extreme force to insert or remove this tool. I have removed quite a few Express and a few 11/87 detents as well using a steel 4 ounce ball peen equally on each side as the tool was inserted and again no problems. The edges of the detents for the magazine spring retainer are fairly sharp so extra time is required to make the transitions smooth top and bottom but afterward only one of the tight fitting stainless followers will give problems. I would suggest if the tool doesn't work or is too tight anyone should take the shotgun to a qualified gunsmith and have the dent or detents removed by a more knowledgeable person. For a replaceable tube like Mossberg just buy and replace the tube. The Remington tubes are soldered in and will require re-blue if you mess it up. It might help to have a stepped mandrel design or other diameters for some of the slightly smaller I.D. tubes.

I got this because all and all it's the best means for a non gunsmith to remove dents and dimples from a mag tube, that being said it functions nothing like Brownells official video demonstration.

Per the instuctions I coated the interior of the mag tube and the exterior of the raiser with gun oil, as I started inserting it the raiser got stuck.

Brownells has no troubleshooting guide nor any proper means of remedy so I had to improvise with a steel hammer, 'nail strikes' had no noticable effect so I had to use 'anvil strikes' in order to completely insert the raiser into the mag tube to facilitate removal.

Fortuneately the tube was not damaged and what I sought to remove had been resolved, but when I reassembled the weapon I found that the mouth of the mag tube had been slightly enlarged, the action, barrel, and mag cap took effort to reinsert.

The fact that the mag tube's diameter would be affected with use should've been disclosed.

Did raise the dents a little, but I still had to file quite a bit to make everything fit right. Also had an issue with getting the barrel to fit back on correctly after I used the tool.

This was used on a Remington 11-87 Sporting Clays semi-auto 12 ga shotgun for the purpose of removing the dimples in the magazine tube so that a Choate brand "9 shot tube extension" could be installed & utilized.

I followed all instructions throughout this process (cannot get any more straight forward than this).

After using the tool on my 11-87 tube about 5 separate times it still would not take out the dimples entirely. The shell follower still hung up SLIGHTLY on the magazine tube dimples. The tool is probably off by several thousandths of an inch in my opinion. I had to file down a good bit of metal with a rat tail file in order to allow the shell follower to smoothly pass by the dimples.

Another noteworthy detail: Even with ample lubrication, the tool required HEAVY striking with a hammer. So much to the extent that it started damaging the end of the tool that was to be struck. The video demonstration on this website and on YouTube show the guy barely tap it down, which I believe to be extremely misleading at least in my case with my particular model shotgun.

The price is super high for a tool that does only one very specific job but I do appreciate the fact that it is made in the good old USA (that's hard to find nowadays).
Being that it is manufactured here in the USA, the high price would not bother me if it functioned a little better and accomplished what it was advertised to do.

Conclusion: This tool DID allow me to get my magazine extension tube kit to function eventually. But only after additional work on my behalf was this accomplished. I was hoping to avoid any filing or drilling of the metal.

I was wary of using this on an 870 Express, based on the other review, to fit an extended mag tube. However, by using some very basic metalwork skills (ie lightly tapping on and around the factory dimples with a hammer to re-stretch the metal), it worked like a champ. I even used it to fix another mag tube on an older gun that was slightly crushed by a previous owner.

Brownells might want to update their Tech Video on the 870 mag tube.

I'd give it 5 stars, except it is a bit pricey.

Brownells has a video on youtube (probably also on the Tech Videos section of brownells.com) saying you can use it to flatten out the dimples on 870 Express magazine tubes if you want to install a magazine extension.

I do *not* recommend this method. I used that dent removal tool on my 870 Express and then came the problems ...

I ended up with an oversized magazine tube, making it difficult to put the barrel back. Of course the two dents where still deep enough to cause the follower to stick ...

I ended up drilling out and sanding both "dimples"...

I think that tool would probably work great as a dent removal tool (hence the name !) but I think Brownells Tech video telling you it can be used to remove the two dimples on 870 Express magazines is misleading.

That tool should be used only as a dent removal tool and should *not* be used to try and remove the dimples from 870 Express magazine tubes.

Fits Remington 870 tubes. I also have a Baikal MP-153 (sold as the Remington SPR-453 in the US) and the tool doesn't fit. The magazine tube on the MP-153/SPR-453 is tighter.

I'm also going to send an email to Remington about those useless dimples on the factory magazine tube !