Is Chamfering necessary?

[nyc71]

I purchased 500 boattail round, I noticed the bullet (Hornady FMJ BT) fits on the case without Chamfering.
Is this step still necessary?
Thanks in advance.


"They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety"- Benjamin Franklin

 

[SentinelStrategic]

On fresh brass that is proper size, you don't. However, if you fire and resize your brass, you'll need to.

 

[R.W.Dale]

Don't expect knife edge accuracy from fmjbt bullets even if you prep your brass to the nth degree. So realistically you most likely won't notice anything amiss downrange if you skip chamfering. In fact if they come out of the barrel and fly in the general direction of the target your already well ahead of the game with 147 g FMJBT bullets




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[jmorris]

Not always. A sharp bit on a trimmer that leaves no burr will be fine. I have trimmed 10's of thousands with a Dillon trimmer and never have chamfered, using jacketed.

 

[GooseGestapo]

Depends on the brass. I've seen some brass even after chamfering have a sharp enough edge that it still shaved a small sliver from the sides of boat-tail bullets.

I've even found that in some instances, that using a Lyman "M" die (an expander with a slight trumpet bell flare normally intended for use to expand the case when loading cast bullets) will help significantly.

Such was the case with some Remington nickle plated .22Hornet brass when I was loading some Nosler 40gr Ballistic Tip bullets some 12yrs ago. By using the "M" die, I saw my groups shrink from 2moa to 3/4moa.

 

[USSR]

Don't expect knife edge accuracy from fmjbt bullets even if you prep your brass to the nth degree.

+1.

Don

 

[Art Eatman]

Chamfering the case mouth will keep the sharp edge from scratching/scraping at the base of even a boat-tail. That's a baaaaaad place for hickeys.