This is what I tried. IMR 4350 @ 69.3 grs.with Hornandy 180 gr. btsp interlock seated at 3.402 2 1/2 in groups at 200 yds, IMR 4350 @69.3 grs. with nosler balastic 180 grs.3 1/4 in group at 200 yds, IMR 4350 @69.3 grs 180 gr.rem. cor lokt 4 in group at 200 yds. I also tried these same combo with IMR 4350 @ 70.0 grs.the nosler balastic went crazy I was all over the paper, the other 2 were about the same.I reseated to 3.340 and started all over, at the 70.0 gr of IMR 4350 with hornandy was still at 2 1/2 in at 200yds noseler ballastic still close to 4 in. group, rem cor lokt was at just hair over 2 in.The last group was with IMR 4350 @ 69.3 grs Hornandy was 1 1/4 rem cor lokt was a hair over 2in. noseler were still out there close to 4 in. These were all 5 shot groups. I cleaned the gun every 15 rounds. It took me just about 8 hrs today. But I loved every minute of it. It got frustrating I had to quit for hour then go back to it but this is best I can do with the equipment I have. Thank you all again for the response
Over the years I have had 5 different 300 Win Mag's and not one of them has liked IMR4350 ,some people I have talked to have had some success with it but not me. my previous 300 Win Mag loved H4831 but the one I presently shoot absolutely hates it ,but it loves RL22. I have seen very few 300 Win Mags that wont shoot RL22 well. what I am telling you is try a different powder and if you still cant get acceptable results find a gunsmith with a borescope.
Brian, The gun shoots excellent at 100yds with IMR 4350 powder at 69.3 grs. using rem corlokt 180 grains seated at 3.340 5 shots group could cover with a quater. I shoot a Ruger M77. But for some reason I cant even come close at 200 yds at 300 yds its a joke little over 5 in group. I know this is in the kill zone but I want to do better like to get it down to at least 2 1/2 group at 300 yds. So when I do go out west to hunt I'm confident at that range.
The reason I suggested trying RL22 or a different powder is because I had the same problem with one of my guns a few years ago,a custom 6mmAI that would shoot half MOA at 100 yards and half moose at 300 yards a simple change of powder straightened it right out,imr4350 is a bit on the faster burn rate for a 300 WM and RL22 is on the slower side it is worth a try
p.s.try RL22 with another bullet also the Rem corlokt is a junk bullet
Terry, I've read your other post and I'm far from an expert first thing I'd do is change scopes next I'd change powders. I just pick up my new custom 300mag tues and getting 3 shot groups less than 1/2" at 100yds with those rem 180gr bullets and H-4831SC haven't shot it a 200 or 300yds yet but it should do pretty well has a Krieger barrel. My other 300mag has a Lilja barrel and I use the same load gives about 1 1/2" at 300yds and in the last 3yrs that rifle has taken a pretty nice 6x6 and 5x5 elk plus one cow elk,one coyote,one bear and 2 deer all with 180gr rem bullet. I've given that rifle to my nephew and the new one is it's replacement. I was playing with a 300rum last year and found some loads shot good at 100 and lousy at 300 (our range only goes to 300yds) shot afew different powders the rifle had a bedding job,recrowned and trigger job plus I changed scopes fired less than 75 rds and that rifle is my new 300mag. As I get older I set less rds trying to get something to shoot. Another thing you could do is buy a box of factory loads and see how they do at 100/300yds. Just my .02. Tom