Jamming Issue, need some pointers

[Texas Sheepdawg]

The 450 Bushmaster Factory Magazine Modification.
NOTE! Consult your local laws before proceeding with this modification.
http://www.youtube.com/watch?v=L29stF3IyOw

[Jeepejeep]

Nice video. One of my mags has those tabs and I think I'm gonna flatten them. NY hunting law is 5 rounds and no more than 10 at any time so I'll make up some kind of block for hunting season. Thanks!

[9x19MdM]

No tabs on either of mine (2) and my spring looks very different.

[Hoot]

The tabs and fix were covered in some posts here and here a while back. Different corrective action, similar results.

Hoot

[etijsma]

I have only shot mine Very little but it would only jam on the first round if I had 5 rounds in the mag. So I was gonna tear my mag apart tonight.

[Texas Sheepdawg]

Once I flattened those tabs, all my issues disappeared. I didn't have any feed issues with the Sig mags.

[etijsma]

just took mine apart and i have no tabs but it does have a spring that has a lot of extra at the base (like the pic above). i cut off about 6-7 coils and it now tightly fits 6 rounds but ill see if that fixes the problem with 5 rounds.

[MrRowdy]

My mag came with a green follower under the blue single stack follower. It also had what appeared to be a 30 round spring with the bottom half smushed, like permanent coil bind. I thought the finish looked like Poo anyhow so I took another 20 round .223 mag and removed the green follower and installed the blue follower with the normal 20 round mag spring. It now fits a VERY snug seven rounds but feeds reliably. I also felt that the mag feed lips were a little loose allowing the rounds to ride nose high so I squeezed them in a vise a bit. I also polished the feed lips because my brass was getting pretty mauled up by the sharp edges. Dumb thing was I did all this before ever firing the rifle, I just saw all these problems as soon as I took it out of the case.

[Hoot]

My mag came with a green follower under the blue single stack follower. It also had what appeared to be a 30 round spring with the bottom half smushed, like permanent coil bind. I thought the finish looked like Poo anyhow so I took another 20 round .223 mag and removed the green follower and installed the blue follower with the normal 20 round mag spring. It now fits a VERY snug seven rounds but feeds reliably. I also felt that the mag feed lips were a little loose allowing the rounds to ride nose high so I squeezed them in a vise a bit. I also polished the feed lips because my brass was getting pretty mauled up by the sharp edges. Dumb thing was I did all this before ever firing the rifle, I just saw all these problems as soon as I took it out of the case.

The first generation mags were made that way. The second generation had the newer black followers, but still with the excess spring in the bottom and the current generation has the black follower, with less spring coils, but those obnoxious PC tabs.

Hoot

[Jim in Houston]

If you buy the blue followers to convert a 223 mag to 450, it is installed on top of the green follower to get what you describe. You may have to trim the blue follower to conform to the inside of the mag.