Broken Charging Handle


@Kona The Forum Bot is fussing at me for replying to you again, but I did quickly draw up an image so you could better see what it would actually look like in context with the receiver.


Since it sounds like the winged charging handle design will never actually be made, I might as well throw out some ideas without regard to whether they are cost effective or whether they make me look stupid.

  1. The charging handle with wings really should be sold with a replacement recoil spring equipped with an end designed to mate solidly with the CH notch and hold it in the proper position against the bottom of the receiver with minimal play as suggested in my post above.

  2. Doing that also presents an opportunity to modify the strength/tension of the recoil spring to achieve a reduction in felt recoil, although care must be exercised not to impact ejecting or feeding reliability. A replacement KT recoil spring sells for $9.45 and the MCarbo RCH sells for $29.95, so the cost of the winged CH and a replacement recoil spring together should be in the neighborhood of $40.00.

  3. The shaft of the CH really should be larger but that would require a replacement bolt. The bolt would be drilled for a much thicker CH shaft and the CH shaft itself could then be enlarged accordingly. Such a bolt also should be about 3-6 ounces heavier than the OEM bolt as opposed to the 14.4 ounces of the KT heavy bolt and could give even greater felt recoil reduction than the RCH (2.2 added ounces) without the fracture risk and without adding undue weight to the firearm. The recoil spring is already larger than the mating surface of the CH shaft so it would probably work just fine with the modification; OR the bolt could be drilled for a larger recoil spring as well. I will defer to the real firearms experts on how realistic and accurate these suggestions are.

For comparison, the KT heavy bolt sells for $45.00 so a replacement bolt would presumably cost around the same. The total quoted for all of those components is $85.00. Even at a 25% premium over the quoted numbers, all of the components together still should cost less than $110.00.

A manufacturer looking to bundle and upsell multiple components can make a separate profit on each of the three components being sold and has a chance to sell related components as well. $110 is nothing to many buyers looking to upgrade and what is being offered is potentially a bargain with not just a more reliable CH but significant felt recoil reduction as well.


@JoeFridaySays Can’t speak for MCARBO at all but if you offer them a product that works better and can be made for a fraction of the cost than their current product then why wouldn’t it be made?

As a shooter in competition I would be interested in any combination of upgrades that slows down the mechanical impulse (faster recovery times) and does NOT add significant weight to the weapon. :+1:


My perspective on firearms and meager contributions to this discussion comes from research into the history and development of weapons and having taught 8th grade physical science. Lol

For a simple, open bolt, blowback weapon there are 3 basic methods to delay the cyclic rate: 1. Friction between diagonally cut metal surfaces. 2. Inertia from a counterweight. 3. A spring with greater tension and resistance.

Most of the simpler weapons use a combination of the last two.

There is another class of blowbacks that shoot from the closed bolt, use a cam action and relay upon the inherent friction and movement of various parts to delay the cycle.

To slow and you get FTE, to fast and you get dangerous venting and even catastrophic fails.

The key to all of these solutions is cost and the ease of manufacture. It needs to be cheap and effective to survive in the market.

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“For a simple, open bolt, blowback weapon there are 3 basic methods to delay the cyclic rate: 1. Friction between diagonally cut metal surfaces. 2. Inertia from a counterweight. 3. A spring with greater tension and resistance.”

So wouldn’t the two modifications described: a slightly heavier bolt and a modified recoil spring, probably be the most cost-effective ways to accomplish your goals while still keeping the firearm light? And a replacement bolt could be drilled for a larger CH shaft that would reduce the fracture incidence of that component. While I think the winged design offers advantages, the increase in shaft size alone might be adequate to solve the fracture problem making the two finger or skeletonized CH with a larger shaft perfectly adequate. I think the extra weight of the RCH is still a potential problem even with a bulkier shaft and that weight is not needed with a heavier bolt.

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However, I think as we bat around this idea it is important to keep in mind fabrication methods and production costs.

Round parts turned on a lathe will cost more than flat parts that can be quickly cut on a CNC machine or a water jet. (Time is the factor - the longer the machine spends on making that part the more $$)

Parts that require the individual skill of a human operator are even more $$.

I assume that MCARBO has a relationship with KT that would allow them to buy in scale blank counterweight or even 80% cut and allow them to modify at a fraction of the cost.

But what intrigues me the most about your design is the radiused wings on the CH. They dont have to be larger than the existing CH base to be effective. (@Kona shouldn’t get pinched). If they are made from polyoxymethylene such as delrin or even some other type of thermoplastic that can handle friction and heat with a high strength:mass ratio then I think it would result in a CH that is extremely cheap to fabricate, out of a much less expensive material, without the need for additional costs.

I know @CatFood is prototyping a reinforced version, and all of your ideas about the spring, rebored counterweight, etc are good ones! (And it may come to that for a permanent fix).

But what if just the winged CH handle made of thermoplastic with a unit production cost of about .75 cents solves the problem?

A cheap, simple solution is always the best! :grin:


@JoeFridaySays @CatFood @Kona

I don’t know if anyone else realizes this but we have basically put together a pretty good design team here.

We have an illustrator/designer who understands mechanical principles and shapes. We have a firearms historian with mechanical background. A fabricator who can make prototypes. And a beta tester who can apparently break anything! (If it survives Logan then I will have confidence in it!)

what started out as just a simple “what if discussion” has actually evolved into me hoping that this gets made and put into production someday by MCARBO.:+1:

That is why I keep pointing out production costs and fabrication methods. :grin:


Hahaha! When did I become the “give it to Logan” test?!


@Kona in my mind at some point it was ALWAYS gonna be the “give it to Logan test!”

Now here is my next point and I want to be real careful how I phrase this.

This was developed on MCARBOs website…it is only right that @ChrisNelson gets first crack at this. Also each of us had a hand in its design (especially Brian) and I don’t know how legal claims of ownership if any exist in such a situation as this? (I just want to buy the part!):grin:

But I would like to see this part made!

The president of my shooting club is the owner of OR3GUN he is an avid 3gunner and big into PCCs his company is like MCARBO in they make performance parts for primarily Mossberg 930 shotguns, he could fabricate this part for us, make different prototypes, etc. (But he will want to sell the finished product).

So I am putting this out to our group as a possibility to make this discussion become a reality?


@Kona @JoeFridaySays @CatFood

I don’t want to belabor the point but I want to make sure you guys understand that I am not being disloyal to MCARBO or being shady and trying to steal the groups ideas and concepts.

But if MCARBO doesn’t want to make this part then I can get it made. But in doing so, and if the part is effective, has a high profit margin, then Bill will naturally bring it to market and in effect become a competitor with Chris! :worried:

All I would like is to see the part made so I can buy it and have a reliable S2K.


@Johnksg I have no idea the acceptableness of what you’re saying right now. It’s never been covered. I will however point out a few things. One, other products currently in production by other companies are freely talked about here and it’s never been an issue. Two, any product ideas not fully realized and in current production I have seen discussed on here were in the spirit of MCARBO creating them (Caveat: I know nothing about the legality of ownership for ideas created here). Three, this is an MCARBO made forum owned by MCARBO for MCARBO customers. That being said, what you’re talking about feels kind of dirty. Lol


I think you should get Chris on the horn and talk 'bout what you want.


@Kona I agree that is why I was so careful in how I said it. I would NEVER do anything unethical. And I want to assure everyone involved that I would NOT go behind anyone’s back. :+1:

That said the PCC market is blazing hot right now, and in my years in the firearms industry I have formed associations and friendships with both 1st and 2nd tier manufactures who can bring a concept such as this to reality.

My hope is Chris pursues it so I can buy it someday! :grin:

I am putting out there as a possibility…Bill could make a whole bunch of prototypes but naturally he would want to develop the product for sale at some point.

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@Kona in fact now that I have said this I am worried that if another OEM brings the product to market I am gonna get blamed! :scream:

(It is a public forum after all and can be viewed by a lotta folks)

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@johnksg like I said I don’t know. People talk about Performance Services and Wicked and other direct competitors of MCARBO here freely all the time but it’s always been about already in production parts. You’re talking about an idea created here. I just don’t know MCARBOs feelings on that and Chris would have to personally weigh in.


@johnksg yes I am a moderator here and there is a certain expectation to monitor the content here in the best interests of MCARBO, but I’m not the idea police either and I’m sure Chris wouldn’t want me stifling creativity either.


@Dred @Kona. What is that old joke about putting a bunch of monkeys in a room with typewriters and give 'em a 100 years eventually one of them will bang out Shakespeare?

I am thinking us monkeys might have done just that!

One of the issues that keeps the S2K from being a serious PDW, as discussed elsewhere is the CH. As mentioned there are other companies making these Chs but they are all basically the same with the same issues…

Maybe you should use your top secret, moderator hotline and get Chris on the phone before we go any further?


John …

If you come back in a week after the creation glow has faded, will you still be as eager to get one in hand? That is rhetorical. There is a whole lot of product development left on this poly CH table. I’m not certain you have a market yet. I figure there are a couple hundred Type-Me’s out here that will grab most anything under a couple $hundred just to give a try. With only a couple hundred buyers, production costs raise prices.

I just don’t categorize a CH failure as imminent. I’m sure I can make mine fail for trying - but mine shows no stress from my gorilla’d abuses. I have the factory par as a backup until I get into mods at the connection point.

But, I’m not moving off my Recoiless until it fails or Chris upgrades the Skeletonized with the beefier Recoiless attachment like he did for the 2 Finger. If this design comes up and all the associated drama gets solved, I’ll consider adopting it. But to point of example, I like my bolt tube cover more than I expect radiused, close riding wings will.


@Kona believe it or not I went back and read the old threads when you guys transitioned this forum from facebook.

Chris created a playground.

But eventually a marketable and valuable product idea was bound to come about!

I have seen this before, guys sketching out ideas on napkins over beers after a shoot and the next thing you know a company is born! (Mike Dillon comes to mind)

I am just a shooter, a guy who is fascinated by history and evolution of firearms designs and wades into the obscure details…and in that role I have met some really great people in the industry, whom in turn have brought products to market out of those discussions!

Even as we speak @JoeFridaySays is already realizing that there is a whole bunch of products that can be made and parts to be sold from this discussion.

In the free market the best and cheapest idea wins!


@Dred you are 100% right sir…someone must take the risk to transition an idea to a product. It may not work at all!

But if it does?

And is cheaper and better?

They will expect to profit!

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