Steve Rose

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There is no discernibly difference in pattern or velocity between a 26” or 28” shotgun barrel. Pick the one that feels/swings the best for you. The birds will never know the difference.

Sure you can shoot trap with that SBE! Give it a try, it may be all you ever want or need. After you determine if you like the game you might decide to go all out and get a dedicated trap gun, By then you will have seen what everyone else is using and be able to make comparisons and best choices on the way to proceed.

http://www.midwestgunworks.com/page/mgwi/ctgy/benelli-barrels Get your checkbook ready. Benelli barrels don't sell for 870 barrel prices

By design the bolt will only lock open when the mag tube is empty.

Briley should not drill all the way through the release button when installing the oversize tab. While tapping a through hole is easier/quicker than tapping a blind hole the though hole weakens the press fit area of the part. (I know that does not help your immediate situation - but if you start over with a non-drill & tapped bolt release it is something to keep in mind)

According to the Nordic Components info the Stoeger M3000 (and M3K) do NOT use the same connecting nut as your Benelli Super Nova http://www.brownells.com/shotgun-parts/magazine-tube-parts/magazine-tube-extensions/stoeger-m3000-m3500-modular-extension-tubes-prod81153.aspx

When you manually pull the bolt back the bolt should not initially lock open unless there are no shells in the magazine tube AND you have pressed the shell release lever (the silver tab close to the trigger). The area you are finding that the bolt stays open is not really “locked open”. That is the why the bolt release does to work. The bolt is hanging on lifter dog. This bit of geometry does not happen when there are shells coming out of the mag tube. So the answer to you question is “No”, this is not a problem. If you manually cycle the bolt and get it the hang in the open position then just push the lifter to get the bolt loose again, but this is not going to happen when firing.

To a certain degree a loose extension could let the barrel turn and front sight cant (obviously the mag tube tube will limit how far the barrel turns when assembled). I think I've seen one loose Benelli extension and a few other brands (Remington 58 ?, maybe an A5 ?...its been a while). In each case cleaning up the parts and a good does of red Loctite got every thing back together.

Just keep in mind that a shell does not come out of the magazine tube unless the hammer falls or the drop lever is pressed. You will be used to it in no time. The drop lever design comes in real handy when you want substitute a shell in the chamber (swap a in shell with larger shot, slug, etc). Just pull back the bolt, eject a shell an insert a shell in to the chamber. The shells in the mag tube never move.

Does the bolt fail to turn into lockup when firing? or only when hand cycling? The bolt is moving forward with much more velocity when fired and if no problem exists then I would not worry about it. If the problem exists when firing you can smooth off the extractor cut in the barrel (20,000 rounds is enough for the extractor to wear a groove into the barrel metal). No need to remove a significant amount of metal, just smooth off any rough edge or groove with 320 grit sandpaper wrapped around a small square file or flat wooden stick. I'd likely install a new extractor at the same time just to be safe.

Can you post a picture? I think I know what you are referring to but I'd like to make sure.

I know it looks “cheap” but if it is made from the right type of plastic/polymer it may actually be tougher than the metal part (bend instead of break). As you know, the 870 went through this change some time back too,

Yes, after machining for the tube the remaining barrel wall thickness needs to be at minimum 0.015”. This translates to an OD of .845” or larger for Rem-Choke tubes, .825” for standard Tru-Choke tubes or .805” for Tru-Choke “Thinwall” tubes (but Thinwall tubes are generally recommended for lead shot, target velocity loads only). If your 13/16" is exact measurement then "Thinwall" tubes are your only option....but check that OD with a good dial caliper or micrometer. Another .013" or so may open more possibility. Steve Rose Rose Action Sports, LLC http://www.roseactionsports.com

What is the outside diameter of your barrel at the muzzle?

Somewhere in the evolution of the SBE and SBE II the ejector was re-designed and the shape of the rib was changed too.

That grip cap can come out when the stock it twisted too much (or shot through the wrist area....long story LOL). The part is not listed as an available part from any of the suppliers which leads me to believe it is considered a part of the stock body. A call to Benelli's customer service might turn up a new part.

Surefire once made a forearm with a light, but it may be discontinued. Freedom Fighter Tactical has a made is USA forearm that is a similar style to the factory design.

I resemble that remark!