cannelure bullets

[The Sodbuster]

Some time ago I picked up some Hornady 100 grain, .257 caliber bullets for my .257 Wby Mag.  After I got them I noticed they had a cannelure.  I don't normally crimp any of my loads and for that particular cartridge, I use a Forster die that doesn't crimp.

I still have the bullets.  Haven't tried them yet.  I assume it's OK to load cannelured bullets without crimping them, but wasn't entirely sure.

[dw06]

Sure is ok without crimping.Some of my best deer hunting loads are with 150-165gr hornady that are cannelured,I just seat them to the oal the rifle likes and never crimp.

[Don Fischer]

I know someone will correct me if I'm wrong here but I believe the only Hornady bullets that aren't cannelured are the interbonds. I saw a photo of an interbond once but have been shooting Hornadys spire point and interloc's for a long long time. Shoot away! I wonder why they do put the cannelure on them anyway except for crimping? Shoot, I load most my bullet's so far out that the cannelure doesn't even reach the case mouth!

[trotterlg]

Lots of hornady bullets without a cannelure, and lots of rifles need a crimp, tube fed rifles, and heavy recoil rifles, single shots and the like don't need them.  Larry

[bearfat]

And as long as we're talking about cannelure bullets why is it with my Lyman magnum press when I am seating the bullet I can tell exactly when the cannelure has reached the mouth of the brass? All of a sudden the pressure of seating the bullet drastically reduces. Anyone else notice this?

Apparently only at the the very edge of the neck/mouth is the greatest restriction. I believe I also read that somewhere. If that is the case wouldn't some cannelure bullets have enough slop or play in them you could slightly move them?

Attached pic shows a winchester 5.56 factory (center) with a crimp style I don't believe I can reproduce. Is it a better crimp style?

[dw06]

And as long as we're talking about cannelure bullets why is it with my Lyman magnum press when I am seating the bullet I can tell exactly when the cannelure has reached the mouth of the brass? All of a sudden the pressure of seating the bullet drastically reduces. Anyone else notice this?

Apparently only at the the very edge of the neck/mouth is the greatest restriction. I believe I also read that somewhere. If that is the case wouldn't some cannelure bullets have enough slop or play in them you could slightly move them?

Attached pic shows a winchester 5.56 factory (center) with a crimp style I don't believe I can reproduce. Is it a better crimp style?

I uae a RCBS rockchucker,and never noticed seating the bullet pressure reduces.As far as being able to move them,why would they be any different than any other bullet?Still have the same neck tension on them.

[bearfat]

If the tighest tension is right at the mouth on the neck, once it reaches the cannelure it can release some of the tension inside the groove. It would be probably be minuscule but I'm thinking there is only a few thousands anyway holding the bullet in place.

It's happened with both (different caliber) cannelure bullets I use, and it didn't matter whether the brass was virgin or fired x3.

Neck tension being mentioned...what causes a constant weak tension in a neck. Is the brass simply worn out if you can't resize the neck down to grip the bullet?  I always full length resize because I've read of too many problems neck sizing only.

I have a crude method of pass/fail after the bullet is seated. I seat the bullet and measure it. Then I push the tip of the bullet into the soft pine end of the 2x6 under my press applying slight pressure. I remeasure. If the bullet moved at all it is marked and only fired as a single shot, and I never run it through the bolt. 

[kyote]

bearfat,
           Attached pic shows a winchester 5.56 factory (center) with a crimp style I don't believe I can reproduce. Is it a better crimp style?

you can reproduce that crimp.you need a Lee factory crimp die.they are easy to use and work fine.they sell the factory crimp die caliber specific.

[beemanbeme]

I think if you'll put a bullet up next to the case mouth, you'll find that the channelure reaches the mouth of the case just about the time the base of the bullet has passed alll the way thru the neck so there's no more resistance of opening up the neck. 
I think its Hornady that sez all of their HUNTING bulets have channelures. One for the obvious reason but also I think its  to help lock the core in and control the expansion.

[bearfat]

beemanbeme I thought you were definitely on the right track, in fact when I read your post I said, "Ahhhhaaa that makes pefect sense!"

Until I did compare. I'd tried to upload a pic but it won't let me, says the folder is full and notify administrator. The bullet is way past the bottom of the neck, almost .30 of an inch.

kyote I do have one Lee die for my 25-06 but never used it yet, using the RBCS. I think the Lee came with a crimp? I'd have to dig it out to confirm.

Anyway Winchester and Lee use a similar crimp on the 5.56 which appears to be a six sided crimp. (The pic not the best highlighting what I thought was an unusal crimp I have only found on Winchester factory 5.56 rnds)

[kyote]

Bearfat,
            the die I am speaking of is called a factory crimp die and it does not come in their normal dies.it use's a collet to make the crimp.and is actually a pretty neat die for crimping.and with it you do not need to worry to much about case length.I use it a lot for loading ammo for rattle guns..good luck.