Hi Duane. The part looks a little light and may be home made. The design looks O_K if it meets the chain correctly but the metal looks too thin to take much beating. I would think 1\4" would be more appropriate .
The chain stripper should not require a lot of strength if the gypsy is correct for the chain size. If the links are slightly short the tension would all be on the link farthest advanced on the gypsy until knocked off by the chain stripper at which time the tension transfers to the next link giving the stripper a beating in the process.
If the chain and gypsy are a good match the tension transfers to earlier link allowing leading link to fall away easier.
There are many chain sizes, some only slightly different. Most gypsys are marked for chain size ,stamped somewhere on the gypsy. When chains stretch from wear they tend to fall away earlier and eventually slip a cog when under tension. A worn gypsy can have the same effect I believe. I have a similar problem as I have a Lofrans Tigress windlass with a gypsy with no markings. Gypsy is unworn but I'm having devil of a time to ID it.