I'm working on an idea. This design idea prevents the use of a normal AR Charging handle so I need to design a side charge handle into my design.

I think it'll have to be reciprocating at least at first.
So slot milled in side of upper of course.

Question is how to best secure the handle in the bolt?
It needs to be easily removed so the bolt can be removed for cleaning.

Most side chargers are just threaded in but do they stay? Most I can find on the market secure via a bolt so the handle can rotate freely.
My design puts it in the gas key.

I haven't seen a steady stream of CH handle bolts exiting side charger carriers. Why not that style or the Gibbz non-reciprocating type?

I converted my 9mm Colt pattern AR to an active left side charger.  It was pretty easy.  Milled a .250" wide slot in the upper receiver.  Made a new gas key and threaded it to accept a 1/4" shoulder bolt.  Shoulder bolt needs to be retained with blue LocTite.  The 9mm conversion was easy because the 9mm gas key does not convey any gas.  If you are going to do this on an AR-15 you will need to make a gas key that carries gas and has room for a 10-24 thread.

Jim Skeel

After much debate with myself and just staring at the BCG and Upper Receiver, I also decided to put my side charger somewhere on the gas key similar to your set up. Mostly so I can mill a slot on the flat surface instead of the radiused side of the receiver.

Not wanting to machine a new gas key, I want to make a removable handle to mount on the front of the gas key.

Held in place with a 10-32 Stainless Cap Screw, along with the machined handle from Titanium or 7075 T6 aluminum, will be bonded with an epoxy as well for some insurance. The surface the 10-32 bolt touches will be ever so slightly dimpled with a matching surface added to the bolt. Being careful to to obstruct the gas tube hole.

The image attached shows the upper receiver in transparent blue. And a VERY basic idea for the charging handle mounted to the gas key.

If having a removable charging handle here is a BAD idea, please educate me as to why.

PS... There is clearance for the Bolt Cam Pin to move freely. At least in this model....

The gas key is thin in that area, and if you've got enough compression to keep the handle from being loose and falling off, you may collapse the gas key enough to bind on the gas tube.

Making a new gas key, or piggybacking your charging handle base on the gas key screws at the rear may be a better idea.

I went a different route...

Attached File

I cant really tell what "route" you went from that photo. Care to explain?

My gas key mounting bolts have been staked on either side for each bolt. Which might do some damage just to remove the gas key. It would be much easier to make something that would mount there using longer bolts. But I am trying to avoid removing it for now.

Removing the gas key is no big deal.  So many people act like staking is some sort of black magic but it is not.
Worst case, buy another ~$10 gas key.

As for my setup, I went with a forward,, non-reciprocating handle.
I also somewhat mimicked the ZM LR300 action spring setup, but beefed it up a little.  No buffer, shortened carrier, no buffer tube needed.
I did all this back in 2008, but I've still got the upper, on a folding SBR lower.

Attached File

Attached File

As a side charging AR fan, I'd be weary of mounting the charging handle to the gas key.

1)  The gas key isn't as stout of a part as the carrier.

2)  Mounting to the gas key will move it up a lot on the receiver.  This can cause clearance issues with optics mounts, and at gas key heights maybe even the rail itself.  I had to turn my red dot mount around so the thumb screw on the mount wouldn't hit my hand when cycling my non-recip left side charger.

I just built one using an actual side charge BCG and receiver. Haven't shot it yet but hopefully today I will.
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