300 win mag ammo
 

was just at the range this afternoon plinking around and now seem to have a problem. i sighted in with 150 gr. federal premium speer soft point, cheap factory stuff. dialed in to 1 inch group at 100 yards. opened another box to check at 200 yards and was shooting all over the place, barley keeping the group on the papaer. went back to shooting at 100 yards and same results, all over the place. maybe just got a bad batch of shells or somthing, but i should probably step up to some better ammo. what would you recomend? i only chose 150 grain due to only antelope and whitetail tags this year. i hear 180 gr. are best for a 300. let me know what is accurate.

Some rifles shoot differently with different type of amo. One of me rifles is bad for that.
That is why I don't change amo in that rifle. When I buy amo for that rifle I buy several boxes I even make sure it is same lot number.
One of my buddy's rifle does the same thing.
When a rifle is fussy about amo it dose not care if it is cheep or expensive the rifle will tell you what it likes .
Good luck with that.

I have a Browning A bolt in 300 win mag. My gun liked 180gr remington core-loks, shooting 1 inch at 100yds. Figured I would go for a better round and bought 180gr. Winchester Supreme Ballistic Silvertips. With them I was shooting 6 inches @ 100 yds. Now I have started handloading though, got rounds that are shooting better in the gun and I am going out and shooting more, so more comfortable with it. It all works to help ones efficieny when you go out to kill something.

300WM Bullets
 

IMO, the 180gr bullets are the best choice for the 300WM. My first suggestion for factory ammo is Winchester Suporeme Accubonds or the WS Elite XP3's. NExt would be the Federal Accubonds or TSX or MRX's

As mentioned, try some different ammo, as one 300WM rifle may/will shoot differently than another in the same manufacture.

My buddy had the same issues (10 years ago) with TB Bear Claws...good at 100, but all over and dropping really bad at 200..not even hitting the paper. We tried the bullets I used at the time ( Partition Golds 180gr) and the rifle shot almost as good as mine...both are Sako m75ss 300WM with Leupold Vari-X III scopes. Since 2004 we have been shooting the WS Accubonds, and now I shoot reloads since 2005 and developing loads for my buddy's rifle.