125 gr. 300 Win Mag

NCisler · #1 08-27-2002, 08:24 PM

Why cant I get a group any smaller than the size of a grape fruit at 100 yrds when I shoot a 125 Gr Nosler Bt loaded with Imr 4350 at 75 Grs.

Wahnie · #2 08-27-2002, 08:41 PM

Not every load will shoot well in a rifle. Your rifle doesn't like 125's, or the bullets aren't stabilzing.

You might want to try different powders weight, types or different bullets.

How long have you been shooting?

What are you using this rifle for?

NCisler · #3 08-27-2002, 08:48 PM

I have been shooting for years. Well about 10 I guess. I tried a couple different powders and this was teh best I could come up with. I bought the gun from a cousin who didnt like the kick and Im not sure what Ill use it for. I was just looking for a fast load that was lighter than most in that size of a gun.

Mil Dot · #4 08-27-2002, 10:37 PM

How does the gun shoot regular weight bullets for the caliber say 180 gr for instance? If it shoots those well move to the next level or two down and see if they hold a decent pattern and then move down again and repeat. Sometimes a particular bullet and a particular gun just weren't meant for one another or put on the research hat and put the time in to work up the perfect load combo that will work. Sorry, but I personally don't have the patience to spend puttering around to long. But that's just me.

Good luck!

Rocky Raab · #5 08-28-2002, 10:32 AM

Your rifle is grouping poorly because of odd barrel vibrations at that bullet weight and speed. And also because the bullet is OVERstabilized. Over stabilized? Yup.

Your barrel has a twist rate designed for 180-gr bullets at 3000 fps or so. That spin rate is way too fast for a 125 at 3400 or so. Several things happen with too fast a spin. One, the bullet can be so stressed from internal forces (centrifugal effect) that the jacket can actually bulge or even rupture after it clears the barrel. Second, because it is over-stabilized, the bullet can hold a position that's not perfectly in line with the airflow. If it flies "cocked" off a bit, it will tend to fly in that direction, rather than straight. No two will fly the same, hence the large group.

It's also difficult to get a powder that works well with that combo. Either the burn rate is right but the load density is low, or the density is good, but the powder is too slow. Low load density (partly empty case) can contribute to erratic ignition and burn with some powders. On the other hand, a light bullet won't produce the correct resistance to a slow powder that ignites and burns properly with heavy bullets. Neither combo is good.

Catfish · #6 08-29-2002, 08:03 PM

NCisler,
Try some Speer 130 grn. HP`s. This is the litest bullet that I was ever to get to shoot well out of a .30 cal. rifle at long ranges, good to 300 plus yrds.I would also recomand you try 4831 powder with this bullet. If this combo doesn`t work well, try a slower burning powder with this bullet.