Getting back into reloading with a 300 Win Mag

[Sweet-Tooth]

I got a used Remington 700 in 300 Win Mag and reloading equipment from my wife for Christmas. I'm getting back into the whole deal after having grown up reloading with my dad.
I've tried IMR4350, 4831, and H1000 with Nosler E-Tip, Accubond, and Barnes TTSX 180gr bullets. Most groups were between 2 and 3 inches, and I was very disappointed until I tried the TTSX bullets and got two <3/4" groups with 75 and 76grains of H1000.
Now that I have a load that this rifle seems to like, I assume my next step is to start experimenting with seating depth.
I do have some concerns however. When seating the bullets, my die leaves a very visible ring on the ogive. Is this a problem or indication I'm doing something wrong?
Also, I typically get very thin shavings of copper when seating the bullets, and I'm pretty sure that's an indication of something wrong. I don't get the shavings with my Lee collet die, but from what I've read, I should be full length resizing which leads me back to the Hornady dies and the shavings.

Any advice would be much appreciated.

Thanks

 

[Blue68f100]

Shaving the bullet can be fixed by chamfuring the inside of the neck. They make a VLD chamfur/deburring tool which has a different angle than the std ones used for decades.

In most cases you can remove the seating stem, chuck it up to a drill and polish the sharp edges out so it will not mark the bullet. The other option is get a custom seating stem to fit the bullet your using. Several die mfg companies offer this service. This also can accour if you have way too much seating force.

 

[AJC1]

Two possible problems pop out immediately. Your champfer and neck diameter. How much neck tension are you running

 

[FROGO207]

If you start to inside chamfer the necks the force needed to insert the bullets will be less. Might even stop the ring from happening. Modifying the hole in the center of the seating plug to angle the edge will help eliminate the dents. Or get a custom seating stem as noted above. I would get a different shape stem anyway if it is available. If not get another of the same . Then modify one as needed. If you mess up you already have a backup. I have modified my stems by chucking them into a drill and held a cone shaped stone into the hole until it was what I wanted.

 

[Sweet-Tooth]

Two possible problems pop out immediately. Your chapter and neck diameter. How much neck tension are you running

I don't know how much neck tension I'm running. It sounds like another thing to check now. I assume I measure the neck OD after resizing and after bullet seating then compare the two.

Thanks

 

[Sweet-Tooth]

If you start to inside chamfer the necks the force needed to insert the bullets will be less. Might even stop the ring from happening. Modifying the hole in the center of the seating plug to angle the edge will help eliminate the dents. Or get a custom seating stem as noted above. I would get a different shape stem anyway if it is available. If not get another of the same . Then modify one as needed. If you mess up you already have a backup. I have modified my stems by chucking them into a drill and held a cone shaped stone into the hole until it was what I wanted.

I have some Lee dies on order to replace the Hornady ones causing me these problems. If this doesn't fix the issue, I'll put the seating stem in my lathe and try what you said, sounds easy enough. I'll start chamfering the necks a bit too.

Thanks

 

[FROGO207]

I chamfer all my bottle necked brass on the inside it just makes things work better. You only need to do it the first time and after each ttrimming. You expand handgun brass so it is not as critical there.