Do 140 gr RDFs work in a AR-10? What COAL are you using in a bolt? August 29, 2017, 12:31:35 PM New to 6.5CM. Finished up my DPMS pattern gasser over the weekend (24" Proof barrel, M5E1 builders kit and JP operating system) and am working my way through a case of Norma Match to break him in and liberate some Norma brass. Getting ready to start searching for powder and try some bullets. The Norma factory ammo shoots pretty good and I have a bunch of the 130 gr Golden Targets that I'll start working up.But I am of course drawn to the 140 gr RDF and the .33 G7. I have had fantastic success with the 30 cal 175 RDFs in my RPR (stock 20" barrel) and regularly take them to a 12"er at 900 and a 16"er at 1k (shooting at 6600' ASL is great for the ego). Only problem is the longest I could get them in my Ruger Scout mag was 2.855 which was .1" off the lands. They're supposed to be forgiving, but they're not that forgiving! So I load them at 2.935 and load them singly.I just ordered some C Products mags for the new 6.5CM which supposedly have a max COAL of 2.874. So the question is will this be enough to make the 140 gr RDFs work? They are longer than the 30 cal 175s, but it looks like the ogive is substantially shorter. Interested to hear if anyone has had success with them in a gasser as well as what sort of COAL the bolties are using. My experience will obviously differ, but it should give me an idea if I can get in the ballpark to make them work.