I'm starting to reload for my PTR, and my AR at some point, but all of my current bullets don't have a cannelure, so I shouldn't crimp, right?

The more I read, the more confused I become. Some folks champion neck tension as being good enough, others claim your gun will explode if you mention firing uncrimped rounds in front of it!

So, who here crimps, how heavy do you crimp, and what loads are you using?

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There's three types of crimps:

- roll crimp

- taper crimp

- Lee Factory crimp



With no cannelure you can't do a roll crimp.  



Some people crimp, some people don't.  Work up some loads with and without crimps and see which ones are most accurate for you and go from there

My opinion:  If you have sized the neck properly to get the desired neck tension then you do not need to crimp.  I have shot thousands of rounds through my AR and none of my handload have been crimped.  There is a danger with crimping if you over crimp.  It can actually decrease the neck tension.  I use a FL sizing die that uses bushings to set the neck OD to achieve the neck tension I want.

I always put a small "Kiss" crimp on all rifle rounds, maybe a few .001

I run all my .223 reloads through a Lee Factory Crimp die. I use Hornady 55gr FMJ (with a cannelure) and Sierra 69gr Match Kings (no cannelure) using the same LFC settings. There may or may not be some effect on accuracy, but I get adequate performance (1MOA off a sandbag at 200 using a red dot sight), and have seen enough reoads suffer bullet setback to know I don't want to take the chance. My application is 3-gun, so I favor reliability over any theoretical accuracy gain I might get from a less aggressive crimp.

The LFCD is a permanent fixture in station 4 of my RL550 .223 setup, everything that passes through get's touched by it.

As far as needing a cannelure to crimp into, it seems to me that cannelures are rarely in the same place from batch to batch, espectailly when it comes to cheap FMJs.

I don't crimp highpower rifle rounds unless it;s for a tube magazine rifle. .30-30 and .444 are good examples. I do make sure that I have at least .002" neck tension, I try to never have more than .003" neck tension.

If you crimp use a light crimp. Lee's FCD set for a little tension is probably the best way to go. It does not require every case to be uniform in length. It helps if they are, but will work fine if they aren't.

Applying a crimp is optional. If you don't have enough tension to hold the bullet in place from set back during the cycling of your action, you should reduce the size of your expander ball or experiment with different bullet seating depths.

For any crimp to be consistent the case length has to be consistent. Simple math tells us that.  Now, I shot HP for a lot of years and never crimped 223 308 or 06 rounds.  Not an issue.  What happens is that some people have to mess with things or they use overworked brass and want to avoid set backs so they crimp.
Now, some cartridges NEED to be crimped as related in tubular magazines, revolver rounds.  But, if the brass is good you not not need to crimp.  I would crimp purpose loaded SD 223.  And, let the gun bbl do the talking whether using a crimp affects the accuracy.

1. If your AR explodes because of an uncrimped round, no one will ever know for sure the uncrimped round caused it.
2. If you can objectively satisfy yourself that neck tension alone is sufficient then just use neck tension because it is less laborious than crimping.
3. Hornady, Black Hills, Lake City crimp their TAP & military rounds for a reason, not to just make them look pretty.

Do not roll crimp into a bullet without a corresponding cannelure to tuck the mouth of the case neck into.
Taper and Collet type crimps can be made onto the smooth barrel of a bullet with no cannelure.

There are times, on a problem by problem basis, that crimping can solve a problem with poor case tension.  My favorite example is the Wideners .308 168 gn brand X OTM in a refurbished LC once fired case out of a std. RCBS sizing die, seating set to M1A / AR10 magazine length.

I am using the FCD on my Nosler Ballistic Tips and I get sub MOA with them, so they are plenty accurate for me. I also use the same crimp on my FMJ's with a cannelure and they work great also. This is just my experience, yours may vary....

Get the Lee FCD... it's outstanding.  I use it on ALL my semi-auto loads, .223 and .308.

"If you have sized the neck properly to get the desired neck tension then you do not need to crimp". This is what most old high-power shooters will tell you. I was there for years myself. My neck tension was perfect. I got a Lee FCD in a estate sale and it collected dust for a couple of years. After trying the FCD on a few bullets and testing them for accuracy it became clear why some here swear by them. I was shooting in the high 700's and saw an average gain of 11 points over a 10 match period. My theory of why it works has nothing to do with neck tension but more what the FCD does to the bullet jacket its self. Pull a few that have been FCD crimped and look at the Vally's in the bullet jacket. You just completely changed the mechanics of that particular bullet. In some rifle bores the deformed bullets shoot much better.  My 2-cent on the FCD.