Re: My thoughts on my Olympic Arms 22-250 UMAR
I just ordered a UMAR lower with WSSM mags to use with my 300 OSSM and 243 WSSM Olympic Arms uppers. I like to experiment and will check if the UMAR lower and WSSM mag will also work with 50 Beowulf or 458 Socom cartridges and uppers. It looks like it might. A downside of AR-15's has always been their short magazines. The UMAR gives 0.18 inches more (2.40 total), though only with their special shaped mags. They can shoot standard mags but that doesn't give the extra length.