Whitworth the Ranchdog link did not get the desired results for what ever reason.
I looked over both the RCBS and Lyman 300 grain Gas Check moulds. The Lee 310, RCBS 300, and Lyman 300 all look very similar. The Lee looks to have a larger metplate than the others.
I have a Lee 357 Cal 158 gr., a 10mm 170 grain, and a 45 in a 230 round nose. All 3 of these moulds produce very nice bullets. I use them for Defensive pistol matches, plinking, and woods carry.
With past results with Lee Moulds I am willing to give them a try.
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