extended length inner barrel for TM SG552

[ILLusion]

Originally Posted by sherlockbonez

Sorry for the tread jack. I'm in simular situation. I was told by a trusted source that I do not need to replace the piston when I switch from a MP5 barrel to an M4, is this true?

The piston is an unnecessary upgrade if all you're doing is an inner barrel swap. You only need to be concerned about the cylinder. In your case, no swap is required to go from an MP5-A or SD series to an M4 inner barrel)

Originally Posted by The Saint

Hm, what do you think about cutting a Twist barrel? I don't know if crowning it would mess up the grooves.

Sherlock, you don't need to change the piston.

Cutting it shouldn't be an issue. In stock form, they aren't even crowned (or crater-cut). If anything, they look like they have a flat cut and had the edges deburred with an interior deburring tool.

[Kurgan]

Who sells the Twist type barrels?

[The Saint]

Have you tried searching through the HK retailers at the top of the page? They're not that hard to find.

[tedan628]

i m getting my tightbore barrel upgrade JBU-KUAN 6.03 mm this weekend on my SIG552. i cant tell u now, but so far with new tightbore 6.03 mm on my JG HK416, the accuracy improves a lot. More groupings!. Love it.
Does anyone know what's MArui SIG552 original inner barrel size?. Is it 6.04 mm or 6.08mm?.
And any more suggestions for improving my JG HK416 performance?. Well out of the box is already 435 fps. But i heard the gears need proper shimming,if i want it last long...hmm..i dunno how to do it?. Any suggestions of specific parts?

[ILLusion]

6.08mm.