Crimping and neck tension

[Dmagna]

Does crimping a bullet negate setting neck tension with a bushing?

 

[RegionRat]

No.

1+1 may not equal two either.

If you were to measure the bullet pull force of each one independently and then check the sum of the combination, they are often unequal but it comes close enough.

 

[HSmithTX]

If the crimp is over done it can reduce neck tension, brass has a small amount of spring back and the bullet has almost none, just a light roll into a cannelure or something is no big deal where rolling a crimp into a bullet is another thing all together.

 

[Mikecr]

I believe it would affect bullet release, as the neck would have to expand beyond crimp depth before the bullet is free.
That's an extra amount.
But I've never crimped, never would, and haven't tested it.

 

[Lefty7mmstw]

I only crimp on cartridges like the 375h&h 44mag, 405 Winchester where a bushing die would be a rather silly investment or is unavailable, so I can't tell you 100% it negates it. I will say that most people do not crimp as cleanly as they should. It's a bit different story for short range stopping rounds vs. rounds meant to be accurate too.

 

[cajun]

You really shouldn't roll crimp a rifle round. A taper crimp like the lee fcd is better if you are crimping. Too aggresive of a crimp can affect bullet release. So if you are aiming for very light neck tension and hammering on a hard crimp it's defeating the purpose. There has been anecdotal evidence that a moderate crimp can create consistent bullet release and help with velocity spreads.

 

[Dmagna]

This is for a 6mm arc in an ar platform. I have bushing dies and I crimp, didn't know if I would mess up neck tension and mess up my loads.

 

[Mikecr]

You should work up a load with your intended crimping.

 

[Dmagna]

You should work up a load with your intended crimping.

I am just was wondering if my crimp negates the neck tension due to the force of the crimp over the .002 of neck tension. Usually I try to do tension testing to see if it tightens groups or gives more consistency. Just wondering if the crimp negates that

 

[BigDon]

I am just was wondering if my crimp negates the neck tension due to the force of the crimp over the .002 of neck tension. Usually I try to do tension testing to see if it tightens groups or gives more consistency. Just wondering if the crimp negates that

Where is Butterbean when we need him??

 

[Old Rooster]

If you use a Factory Crimp Die do not over crimp!
A light crimp is all I do.You can go to youtube and look up Butterbeans video on how to set up the die.
I use a bushing and I put a light crimp.
When Butterbean gets here he can explain it better than I can.He schooled me on proper use.

 

[Old Rooster]

Here is a link to Butterbeans video:

 

[cape cove]

My take on this would be if you are going to crimp your bullet then I would use very light neck tension and work up your load using the crimp at all stages as @Mikecr posted. I believe this is what the factory does because if you pull a factory round you will notice that after the crimp is broken the tension is light and the factory can load very accurate ammo not having your rifle to develop the load with. JMO

 

[Fiftydriver]

Does crimping a bullet negate setting neck tension with a bushing?

What cartridge are you loading for? Most do not need a crimp and not desirable either. Some applications need it for sure but relatively few.