Is this way too much Crimp?

[moretoys]

Hey Gang,
I'm more of a neck sizing long range kind of reloader, and proper crimping for autoloaders is new to me. I had to pull some loaded 95gr SSTs today, and the amount of distress on the bullet was surprising. (See below) I'm using the lee factory crimp die. Is this normal, or am I crushing it way too hard? FYI These bent up bullets are shooting around 1MOA over 30.6gr of H335, so it can't be THAT awful. Any information or advice would be welcomed.

Crimp marks.jpg

[A5BLASTER]

I'm going to say yes but that's because I do not crimp at all. Proper neck tension will hold the bullet just fine.

Get rid of the Lee dies.

[mel]

I have Lee dies and have never used the crimp die . Never had an issue

[Gtscotty]

A- Yes, that's way, way too much

B- Why are you crimping, normal neck tension should be all you need in an autoloader. I don't think I've crimped a single rifle case within the past decade.

[grayfox]

I have recently begun to use a lee fcd for my 300 BO... it's the only Lee thing I think is worth the $$.
Having said this, yes that's too much crimp. The Lee fcd puts a radial crimp onto the bullet (horizontally all 'round the casing, vice a roll crimp onto the top edge of the brass) so the sides should not be digging in so deeply to the bullet shank.
Something's up.
I don't see a need to crimp any Grendel bullets. Just doing the BO b/c they are relatively heavy for cartridge size.

[bbqncigars]

I only crimp some rounds to keep the bullets from moving either under recoil (revolvers and some lever guns) or feeding (some autoloaders). Also if that particular load needed a neck flare ironed out. That's excessive crimp. Those BT bullets shouldn't need any neck expanding and very little crimp if any.

[FRB6.5]

Believe it or not the ability to do that was one of the features Lee advertised when those dies were introduced. But as everyone has stated that is way too much crimp.

Edit:
It's still mentioned on both sides of the printed instructions even on the newer dies, but is no longer mentioned on the website for the product.

"You can seat your bullets to the best depth - the Lee Factory Crimper forms a cannelure in the bullet as it crimps."
and
"Bullets do not need a crimp groove as the Lee Factory Crimp Die will form one when crimping. However, it requires a harder push on the press lever to form the crimp."

[Klem]

MT

With enough neck tension in an auto-loader you don't need the added step of crimping, and without the Lee design mangling your cases every time your cases will last longer and your group sizes will be no worse, probably better.

Enough neck tension is at least .002", especially if there a reasonable jump to lands. Your bullets can shift a tiny bit but as long as they don't come up against the lands there's no difference in start pressure to cause the classic split vertical group on the target. Another way of ensuring the bullets are less likely to shift is by having enough shank in contact with the neck. It helps if there's at least the diameter of the calibre in contact with the neck - so with Grendel at least 6.5mm of shank. You can check all this by measuring the before and after OAL of a round loaded into your AR when the BCG slams it into battery. If it doesn't shift or only slightly then you are good-to-go without needing to crimp.

Rounds loaded for the military and even factory rounds for civilian auto-loaders (e.g. Gemtech's 300BLK 220SMK subsonic) typically use cannelured bullets. This permits crimping into the void without damaging the bullet like in your photo. It's all about guaranteeing bullets won't budge with any amount of abuse, in any rifle. In your case you have the luxury of loading for one gun with known conditions. You don't need to be so severe.

FYI, Redding makes a taper crimp die for Grendel which covers more surface area of the neck and is a tapered effect. This means it is more forgiving on case length. It is also a lot less severe on the neck and the bullet.

[Mesa1978]

Sufficient neck tension for Grendel has worked in all ARs for me. I only crimp 300 BO SSTs with Lyman SB MSR dies.

[moretoys]

Ok, No more crimping.
I'm on my third barrel trying to get my Grendel under 1 MOA. I was about to give up and sell it, but we'll see if going crimp free tightens up the groups....
Thanks for the great input!
GP

[Old Bob]

Oh wow! I just came on the ammo & reloading page to make a post of my own about crimping for the 6.5 Grendel. Someone - moretoys - already started the topic I was gonna start. The replies to his post pretty much answered my question about the need for crimping. I don't have the Lee FCD (didn't know Lee made one for the Grendel) but I do have the Redding taper crimp die. I guess I might not need it.

I was gonna ask about it for the Grendel 'cause I needed to start putting a slight crimp on the cases for my 7.62X40WT AR when I discovered there was some bullet movement during firing. Wilson Combat even recommended a little bit of crimp when I asked them about it.

I have a related question about Grendel brass but will start another thread.

[Klem]

Ok, No more crimping.
I'm on my third barrel trying to get my Grendel under 1 MOA. I was about to give up and sell it, but we'll see if going crimp free tightens up the groups....
Thanks for the great input!
GP

MT,

I did a 300rd test a while back between taper crimping and neck tension. The groups are 4rds at 100yds, bench rested. Neck tension wins but to be real there's almost no difference.



What barrels are you using?

[FLshooter]

[Mad Charlie]

Crimps and cannelures are not exactly famous for enhancing accuracy.

As has been said, that is way too much crimp.

[Mustangfreek]

Yes..lol..

I usually on crimp a couple of thou