300 blackout question

[Abenaki]

I am getting ready to reload for the 300 blackout.

I was looking at RCBS dies for it and they have a taper crimp die.
Why is this? Why not a regular crimp?

What do I need to know?

Thanks guys
Abenaki

[divingin]

Given the relatively low recoil impulse with 300BO, I, personally, wouldn't bother with a crimp at all.

That said, I think it's an either/or with that. Taper crimp will be more consistent with varying case lengths, but either one will do, should you choose to crimp.

[sigstroker]

Recoil has nothing to do with it unless you only shoot a bolt gun. It's about stopping bullet setback when it feeds into the chamber.

[LynnJr]

Never seen the need to crimp a centerfire rifle cartridge

[L4D]

[Itsrockysmodernlife]

I am getting ready to reload for the 300 blackout.

I was looking at RCBS dies for it and they have a taper crimp die.
Why is this? Why not a regular crimp?

What do I need to know?

Thanks guys
Abenaki

[Itsrockysmodernlife]

Buy yourself a Lyman e-zee trim

[Itsrockysmodernlife]

Recoil has nothing to do with it unless you only shoot a bolt gun. It's about stopping bullet setback when it feeds into the chamber.

Unlikely.

[ar15barrels]

I am getting ready to reload for the 300 blackout.

I was looking at RCBS dies for it and they have a taper crimp die.
Why is this?
Why not a regular crimp?

What do I need to know?

A taper crimp IS a regular crimp for bullets that don't have a crimp groove.
You only use a roll crimp with bullets that have a crimp groove for the roll crimp to be rolled into.
Taper crimps squeeze the case neck against any bullet without damaging the bullet.
You can also taper crimp into a cannelure if you have cannelures on the bullets.

[Itsrockysmodernlife]

Given the relatively low recoil impulse with 300BO, I, personally, wouldn't bother with a crimp at all.

That said, I think it's an either/or with that. Taper crimp will be more consistent with varying case lengths, but either one will do, should you choose to crimp.

[rsrocket1]

The 22401 die set has a roll crimp on the seater die. The 2207 die set has a taper crimp on the seater die and has a small base die as the decapper. I have the 2207 because I put a slight flare on the case mouth when loading 30 cal cast bullets in 300 AAC Blackout and I also make my cases out of 223/5.56 cases so the small base sizing die ensures a minimum spec case body. I adjust the taper crimp to close the flare and bring the case mouth just beyond vertical. When loading boat tail jacketed 30 cal bullets, there is no need to flare the case so I simply use the die as a seater die and the die body doesn't touch the case mouth.

[Abenaki]

The 22401 die set has a roll crimp on the seater die. The 2207 die set has a taper crimp on the seater die and has a small base die as the decapper. I have the 2207 because I put a slight flare on the case mouth when loading 30 cal cast bullets in 300 AAC Blackout and I also make my cases out of 223/5.56 cases so the small base sizing die ensures a minimum spec case body. I adjust the taper crimp to close the flare and bring the case mouth just beyond vertical. When loading boat tail jacketed 30 cal bullets, there is no need to flare the case so I simply use the die as a seater die and the die body doesn't touch the case mouth.

This is what I needed to know.
I kinda figured it out on my own.

I just started reloading for my 300 black out.

Thanks guys
Abenaki

[BrassCase]

Recoil has nothing to do with it unless you only shoot a bolt gun. It's about stopping bullet setback when it feeds into the chamber.

Unlikely.

No, Sig is correct with semi-auto rifles. Bolt guns don't unless you're using it to achieve a uniform tension for some reason.

[Abenaki]

Yes, a crimp helps to stop bullet set back when it feeds into the chamber.

But, I believe that it also helps to stop the bullet from moving forward in a semi auto. When the bolt slams forward, the bullet wants to keep moving forward.
Please correct me if I am wrong.

Take care
Abenaki

[rsrocket1]

I load cast, SP jacketed and FMJ 30 cal bullets in 300 Blackout. I shoot both in a Ruger American Ranch and an AR. I don't crimp any of my bullets and have measured COL before and after chambering (just as a test) and I get zero set back. 300AAC recoils less than 7.62x39 but a little more than .223 so the recoil is not very strong even will full house loads (2300 fps with 113g bullets and 1750 fps with 200g bullets).

Neck tension is sufficient to prevent set back when autoloaders feed the bullet.

Of course the best course of action is to try it yourself by loading 10 bullets in a mag without crimping and measure the COL on the last bullet in the mag after it's fed.