Two weeks ago I was at the range with my Sub-2000, re-zeroing my red dot sight after removing the rail system and replacing it with one from Red Lion Precision (a review of which will be forthcoming) when I went to load another magazine and discovered that my cocking handle had just... disappeared. Subsequent investigation discovered it slightly downrage with all the ejected brass.
This in itself was not too surprising, as I've managed to break one of the cocking handles before (albeit through my own mis-engineering). The design has an inherent flaw, which I shall attempt to describe through prose and pictures since I don't have a cutaway drawing of internal S2K mechanics.
The S2K uses direct blowback in its operation. The bolt (right) attaches to what I am calling the bolt carrier (center) by means of a tongue-and-groove layout. (The bolt rolled onto its back due to weight, so this is not actually how it goes into the gun. For purposes of explanation, however, I hope it suffices.)
The cocking handle (below) sticks through a hole in the bolt carrier, and is held in place by the tension of the recoil spring (above) against the end cap (left).
Now, in order for the spring to index against the handle, the handle is thinned out to match the diameter of the spring (see below). Unfortunately, since the handle reciprocates along with the entire bolt assembly after each shot, there will be stress put upon the handle, and since it's not uniformly thick, it's prone to breaking at its thinnest area
As I said, this wasn't terribly surprising, but it was disappointing; I had been using the extended cocking handle made by Twisted Industries that I received back in January of 2013, and up until this point it had performed flawlessly. What surprised me was that I didn't feel it fly off! I would have assumed that the break would occur at either full retraction or full extension, and yet I didn't feel the broken handle strike my shoulder or my operating arm. I suppose it broke as the bolt slammed home, and then just fell towards my feet and rolled into the brass just ahead of the shooting position.
I don't know if just was just good luck on my part, or good engineering on the part of Kel-Tec and/or Twisted Industries, but either way I'm grateful that this breakage didn't result in injuries.
On the good side, at least I got my red dot zeroed:
Upon arriving back home, I got on Facebook and whined a bit about having a broken part... and then I contacted Harry Perrette, my buddy at Twisted Industries, to see about getting a new one:
Me: Hey Harry, today while at the range my TI extended cocking handle broke and fell out of my Sub-2000. Has this ever happened before? [pictures attached] Do you have any sort of replacement service?
Harry: Yeah, that's why we made them. It's common. Email me your address, we have an updated one. You want stainless or black?
Me: Black please. Do you happen to know how many hundred rounds before it typically fails?
Harry: New ones don't fail.
Me: Excellent. Thanks for your prompt response. I'll talk you up for having good customer service!
And so, by the next week, I had in my hands the newest version of the Twisted Industries Sub-2000 Operating Handle! A quick look at the redesign certainly explains Harry's claims that it won't fail: instead of
being thinned all the way around (easy to do on a lathe, but at the expense of weakening the metal) a flat surface is milled out of one side.
This surface gives the recoil spring something to index against, while hopefully keeping the column stronger.
This design does have the very slight drawback of needing to make sure the handle is oriented the right way during assembly, but I'll take an additional second or two of inconvenience in return for a promise of "won't ever fail" any day of the week.
But will it not ever actually fail, though? Well, that remains to be determined. TI's old handle lasted a year and several hundred rounds -- between 250 and 500, I'd estimate. Going forth from here, I'm going to try to keep closer records of number of rounds put through my S2K, and IF this new operating handle fails, I'll let you know.
Until then, I'm quite happy with mine, and I encourage any Sub-2000 owner to purchase a TI Operating Handle. They cost between $24.99 for the graphite black version and $29.99 for a stainless steel version.
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| Picture from the TI website. Included here because of the awesome "pile of empty brass" quote etched onto the tube. |
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