I do run GT 35-55 in my old 48# Blackwidow HF1225.
Manufacturerd in 1972.
Centershot OK, but had to add weight to insert for perfect paper tune. Dunno speed, don't care.
They fly great, FOC decent.........should work.

55-75 GT with 100gr insert, flew perfect from my 1983 Blackwidow HF58 (59#).

Now that the doc says I have arthritis, why I hurt all last yr, and has me on mild med that makes me feel pretty good.......I wish I had the HF58 back frown

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