Question about setting up dies for bullet depth

[BudgetBucks1]

I have been reloading for a few weeks and noticed that the Nosler custom competition 168 grains in my 30.06 weren't breaking through the paper "clean", the edges of the bullet holes were sort of "torn." I changed bullets and began working up a hunting load with Nosler 165 grain greentip rounds and the edges of the bullet holes were also "torn" but I decreased by powder(IMR 4350) a couple of grains and I started getting clean edges on the bullet holes and I also had a major accuracy increase. I have yet to get "clean holes" with the Nosler CC 168's. I don't know why this is unless the bullets aren't flying correctly and I thought it might have something to do with the seating depth of my bullets. My AK 47 makes perfectly clean holes everytime I shoot it on paper with any of the loads I have tried. Could this also have to do with the velocity of the bullet? I am loading at the very bottom range of the Nosler reloading manual when I get the "clean holes". If anyone has any info on this that could help satisfy my curiosity would be greatly appreciated.

 

[Sam1911]

Can't say as I've ever heard of the cleanness of the bullet holes having anything to do with accuracy. Some types of bullets (like wadcutters and semi-wadcutters) punch very clean holes because they have a somewhat sharp shoulder that shears the paper. Round-nose bullets tend to produce more ragged, torn holes.

Unless the bullets are tumbling and you can see that the bullet did not pass through the target going straight (like you can see a "keyholed" bullet hole because the bullet was tumbling), don't worry about how perfectly cut the bullet holes are.

Accuracy often does increase (or decrease!) when you change powder charge though. And, once you've got a very good load going, you can often improve things further by playing with the seating depth a little bit. Many guns are more accurate when the bullets are seated out until they almost (but not quite) touch the start of the rifling.

Clean bullet holes, though? Forgeddaboutit!

 

[cfullgraf]

Sam 1911 pretty much covered it.

To add, pointed bullets pretty much just push the paper out of the way. If you flatten out the displaced paper at a bullet hole on the back of the target, you will see the hole is pretty much filled in. (Note that larger diameter bullets will cut some paper away. Heavier target boards also affect whether the paper is cut or displaced.)

Handgun wadcutter bullets designed for target shooting cut a clean hole. You will find bits of confetti behind the target as the bullets do cut the paper. The target itself looks like someone took a hole punch to it.

 

[USSR]

What are you using as a backer, and what charge weight of IMR4350 are you using?

Don

 

[gamestalker]

COAL, or OAL is the term used to describe bullet seating depth. It could be that you have too much jump to the lands, not enough, but every gun is different and likes them, where it likes them.

To low / high of a charge can cause problems with the bullet stabilizing. Rate of twist and bullet weight and length plays a role in this as well. I've found that when using IMR-4350 in both the 30-06 and .270 win that lower end charges don't perform as accurately. I usually start around mid point and work my way up until I've found the sweet spot.

As for torn edges on the holes, I don't know, unless the bullets are tumbling, or key holing, I wouldn't necessarily be concerned about how clean the hole is. How is the over all accuracy, are the groups nice and tight?

GS

 

[gibble888]

Use the start charge then work your way up slowly ull see the groups get tighter then start to open up...use the tighest group charge....it doesnt matter if its 4000fps if u cant hit what ur shooting at.

 

[BudgetBucks1]

Thanks for the info. To answer USSR I was using paper on cardboard. The best group with the perfect holes was 52 grains of IMR 4350 for the 30.06 and 165 grain nosler green tip. When I shot the same load with 53 grains the holes in the paper were "torn." The 52 grain produced a 3/4 inch group with perfectly round holes where the edges were crisp like using a hole puncher. I am shooting an old savage hunting rifle and shooting prone in the yard so I was happy with the group. I was just intrigued by the change in the holes in the paper and now and wishing I had a picture of that target to post on here to show you guys.

 

[USSR]

BB1,

First, if by "cardboard", you mean as in a cardboard box, I would use a stiffer material. Secondly, you're shooting minimal starting powder charge weights for both bullets. Maximum charge weight for both bullets is 57.0gr of IMR4350, so I would increase your powder charge weight to somewhere in the middle to see what happens. I have never found low charge weights of slow burning powders to be particularly conducive to accuracy.

Don