Is it necessary to use crimp dies?

Never had much of a problem with 243 brass needing to be trimmed after every firing.
Cannelure is not necessary for crimping bullets.
 
I only apply the lightest of crimp as i am not attempting to GRIP the bullet but merely achieve a more consistent neck tension to promote uniform pressure build up prior to bullet leaving the neck of case.
I always check case length.
I crimp non canneleured bullets.
 
With regard to ensuring consistent and correct case length, so far I have used Sako brass for my .243 reloading (factory bought expanding rounds which I have then re-used), and after 3 fires all of the cases are still significantly shorter than the Lee length guide. Could I still crimp these successfully?
 
With regard to ensuring consistent and correct case length, so far I have used Sako brass for my .243 reloading (factory bought expanding rounds which I have then re-used), and after 3 fires all of the cases are still significantly shorter than the Lee length guide. Could I still crimp these successfully?

To set the FCD you need a uniform case length to achieve a uniform crimp.
 
With regard to ensuring consistent and correct case length, so far I have used Sako brass for my .243 reloading (factory bought expanding rounds which I have then re-used), and after 3 fires all of the cases are still significantly shorter than the Lee length guide. Could I still crimp these successfully?

Just make sure that the length rod on the Lee trimmer is screwed fully into the cutter and check the length with your vernier calipers. Much as I like the Lee length trimmers they will only trim over length cases. In your situation you will need a trimmer that you can set to the length of your shortest case and trim them all to that. A variation of a few thou in the length of the cases will have a significant effect on the amount of crimp leading to varying velocity and uncertain accuracy, especially at longer ranges. This will show up as a wide ES through the chrony.
 
You need uniform case length for crimping, otherwise the crimp will be inconsistent. Loading for a Ruger 30-06 this past weekend using some PMC brass, the cases wouldn't hit the Lee trimmer. We broke out the Forester trimmer and trimmed them all to the shortest case length of the batch. It was just a few thousandths of trim but it made a huge difference; 1.1 inches went to clover leafs. No crimping grooves in those Noslers.

I have not had crimping lessen case life. I have some brass on it's 10th reloading with no problems.

I always lightly deburr trimmed cases but I try to avoid chamfering the case to assist in bullet seating. When I care for extreme accuracy, i use a Lee Universal Expander die to put a light flare on the case mouth that will allow for smooth seating. This die puts a very slight flare on the case mouth -almost imperceptible. I follow with a FCD. Once you use this expander die for seating bullet you'll wonder how you got away without it. The bullets seat smoothly without shaving jacket and no "thump" of the bullet forcing into the neck. Nice.
~Muir
 
Just make sure that the length rod on the Lee trimmer is screwed fully into the cutter and check the length with your vernier calipers. Much as I like the Lee length trimmers they will only trim over length cases. In your situation you will need a trimmer that you can set to the length of your shortest case and trim them all to that. A variation of a few thou in the length of the cases will have a significant effect on the amount of crimp leading to varying velocity and uncertain accuracy, especially at longer ranges. This will show up as a wide ES through the chrony.

Thanks 1066,
The Lee length gauge was on back-order for weeks until I received it, so I was measuring each case with calipers to check they were not over-size. I will measure the cases and batch them to length and try a few crimped to see if it makes a difference.
 
I prefer the Lee case length trimmer, cheap and easy, and if needed you can "adjust" the length with nothing more than a smooth stone.
I have a Lyman case length trimmer, bought to do 6mmPPC as Lee don't make a trimmer, but am now seriously thinking about ordering a special from Lee.
(Mike Norris also offered to make me one when I asked about it at the midland)

Neil. :)
 
Thanks 1066,
The Lee length gauge was on back-order for weeks until I received it, so I was measuring each case with calipers to check they were not over-size. I will measure the cases and batch them to length and try a few crimped to see if it makes a difference.


glad to see your going to try it out!
 
Me thinks folks are confusing the FCD and roll crimping that is oft built into dies like Redding and RCBS.
Doing the former is ok on anything, although I'd warrant not always necessary, the latter really wants a cannelure as when done incorrectly will give you bulged shoulders.
 
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