I initially bought the RT90C to use as a spotting platform for precision matches. After going through some different ball heads I settled on the Sunwayfoto IB-30. I've gone on to use it to great success for varmint hunting, shooting squirrels standing off the tripod from point blank to 200 yards with my 223 and out just past 100 with my Vudoo 22LR (pictured below). The RT90C now seems a bit heavy to be walking around with. I may be in search of a lighter option for next year's varmint shoots.
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When new, the IB-30 held tension well, but after a year or more, it was right on the edge of holding the rifle securely without tipping.
I looked further into the construction of the IB-30 and found you can adjust the tension. Just remove the screw that holds the tension lever and you can then re-index it to hold tighter. Hopefully this helps someone who's displeased with the initial tension these offer.
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