Recently picked up a 28" vent-rib barrel for my Win 1200 Defender, which previously had an 18" barrel.

Unfortunately, the 5 shot tube extends out too far, so that the mag-tube cap doesn't keep the barrel on.

Is there something I can purchase that would allow this barrel to be used with the longer tube?

Otherwise, what is the appropriate capacity magazine tube for a Winchester 1200/1300 with a 28" barrel?

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