I got the Nordic kit that was specific to the 1301 Tactical so the +1 extension ends of even with the barrel and includes the barrel clamp and rail and sling additions that bolt to it. The spring was a standardized length that you just needed to snip (12-16 inched) from the end of the tube when inserted.
My issues were really not a big deal. I don’t have a allot of shotgun experience so I take my time and stare at things until I figure it out. The biggest pain was understanding how to get the spring cap off once you unscrewed the main cap. I was just too stupid to remove the forearm which would have gotten me to my answer much quicker. The spring issue would’ve been solved if I just read the directions. All in all, my fault. It’s reallu a 5-10 minute job.
I have the clamp on mine primarily so I can mount a Surefire X300 on the left of the gun. If you aren't using that real estate to mount a light it's really not necessary to install the clamp.
When the Aridus forend ships I'm likely to remove the clamp from my gun.
3/15/2016
I’d be happy to measure the extension when I get home for you...that’d be a start anyway. I’m gonna just ask the insulting question since I’ve done the same sorts of things myself at one point or another so don’t be offended. You removed the main screw cap then took off the forend and removed the tube cap/plunger spring holder by pushing in the little tab correct? I would think not doing that would certainly account for not being able to screw it down all the way.
Haha!!
It’s 4:30 my time... I should leave the office in an hour or so. So gimme until 7 and I’ll measure the extension that came with my kit.