I've always heard there is no such thing as a stupid question. (Well there really is but...) This may sound simple enough but: Having never used gas checks on any of my cast bullets I have a question. What I am considering doing is buying a mold (.358" dia 200 gr) for my 350 Legend rifle. This mold requires a gas check but I have to size it down to .356" or .357". My question is Will I have any issues installing the gas checks then sizing down to .356"?
Or would it be a better option to just buy .358" 200 gr jacketed bullets and size them down?

Well no need to answer this. I already found my answer. Just put on the gas check and run through the sizer.

Yeup... that extra 1 thou sizing is claimed to even help the gas check grip the base - and since it sizes just a LITTLE less easily than the lead in front of it, it helps the gas check get an even cleaner bite in the rifling to do its job.