best moderate (slower) action 4 pc graphite 8' 4 wt mfg? Recommendations?

To be used for what fishery??
Trout? Nymphing? Dry flies? Bass?
Herb
CTS

PS The Affinity-Vintage in 7'6" #4 is a dynamite dry fly blank.

I’ll agree with Herb about the Vintage 7’6” 4wt. That “Vintage series” of CTS is a fantastic moderate action blank. It is not advertised on the website, but Herb can get you the hookup on that. (Side note: I would buy CTS through him over anyone here in the states.) I have built all the way down to a “0wt” in that series and they are a true moderate action. The only other possibility that I can think of would be to contact Mike McFarland of McFarland Rods directly. He is a gifted blank designer. Also, I know that he and another individual had a line of lower modulus graphite that was rolled on mandrels for more “traditional” taper. I’m not positive about the length/weight combos available, but it might be worth giving him a shout. The other individual has kind of went dark for the time being. I hope that he is well because I really liked a lot of the blanks that he was rolling.

Also some other traditional “dry fly” blanks to consider (if that is what your end goal is) would be the Thomas and Thomas Paradigm, Winston Pure and the Sage Trout LL. Some of these can be hard to get ahold of and, depending on your budget, might be price restrictive.

Jared,
Thank you very much!!
Herb
CTS Rep

Do you have a performance reason for you preferring a "slower" action rod? Will you primarily be casting dry flies, wet flies, or streamers, and at what average distance? Your search for a moderate blank is unusual with "speed" being all the rage these days.

Some of us fly fishers done like the modern “rocket launcher” blanks. I like a more moderate blank.
Yes the old Sage LL series are nice but impossible to find.
The older Batson rainshadow blue blanks are in that category I feel. I bought and built several 8’ 4 wts and everyone liked them. In fact I may even have a couple left.

Another consideration is Winston’s IBIS (I purchased as blank in 2001) though you’d have to research whether they made the IBIS in your desired configuration.

"The greatest barrier to discovery is not ignorance, it's the illusion of knowledge" - Daniel J. Boorstin

The NFC gmma alpha is very nice, but 8’-6”

How about a glass rod?

You can use heavy guides on a graphite rod to mimic the action and weight of a glass rod. A whole lot of record fish were caught on such rods.