Sorry for the lack of reply’s everyone, I’m not new to forge welding by any means I’ve forge welded plenty of stuff without issue. I just wanted to learn to forge weld tong reigns as its a useful skill. If i really needed the tongs I’d draw out the reigns or one the broken pairs I’d mig weld them together. The main reason i didn't on these pairs were they were uneven or a bit thin in places. And I wasn’t urgently needing the tongs. I like longer tongs just outta personal preference. And because now that i have a good amount of wrought iron i can forge weld it together and not get as much splatter on me. Or flux for forge welding. I have some shorter tongs in addition to my longer ones. I will end up salvaging the reigns off these so its not a total waste. The two successful pairs are going strong still. Plus forge welding is fun! I appreciate all the advise though. 

I've found that the lower grades of WI tend to be "juicier" when welding than mild steel.

I would think so. Bigger silica inclusions in course WI. The stuff I have is fairly Well  refined So it shouldn’t be too horrible

Bigger and more by percentage of weight, so even more self fluxing.