when/ or not to crimp

[kemayfield]

First off, I am a newbie to reloading. I bought a Dillon 550, and have a question on crimping. The 550 has a dedicated crimping die. My reloading manual says that only bullets with a cannelure must be crimped. I am planning on loading .30-06 and none of my bullets have a cannelure. Should I not use this die or what? Any feedback is greatly appreciated, thanks in advance

[Sevens]

Really depends on caliber. Sounds like you are talking specifically about .30-06 and nothing else, and in that case, I don't think it's entirely necessary to crimp these. However... I'm mostly a handgun guy and it seems that I learns something new about reloading rifle rounds daily, so I'll be keeping an eye on what develops here.

[Shane Tuttle]

I'm not versed on Dillon dies. I would give them a jingle and see if they're a taper crimp instead of roll crimp. I've never used roll crimping on my rifle cartridges, but that's just me. If your die is a taper crimp variety, I'd make use of it. Just make sure you're consistent on the amount of crimp while working up a load so this variable is a constant.

[rwilson452]

Loading 30-06 for a bolt gun, a crimp is not neeeded. it is suggested for autoloaders. I crimp for my M1 but not for my Mod. 70. I use a Lee FCD. with it a cannelure is not needed.

when/ or not to crimp
First off, I am a newbie to reloading. I bought a Dillon 550, and have a question on crimping. The 550 has a dedicated crimping die. My reloading manual says that only bullets with a cannelure must be crimped. I am planning on loading .30-06 and none of my bullets have a cannelure. Should I not use this die or what? Any feedback is greatly appreciated, thanks in advance

[rn22723]

Just cause you have a crimp die, does not mean you have to use it......
As suggested above.......if you are loading for a bolt gun then no a crimp is not needed. I have shot an awful lot of 223, 308, and 06 that was shot thru auto loading guns, and then never have a crimp applied.... But, you have to pay attention to things. And, the simple answer is do tell us more info like what your intended use of the ammo....and more importantly what platform.

Now, when dealing with most straight walled cartridges you will need to eliminate the belling done to facilitate the seating of the bullet. Most revolver rounds need a roll crimp. And, with most auto loading rimless cartridges you need to realize the case head spaces off the case mouth, so over crimping could be bad deal.

[Slamfire]

I crimp pistol ammo.

I crimp rifle ammo used in lever actions. That turns out to be the 30-30 and the 44 Mag.

I do not crimp any other rifle ammo.

However if I was shooting elephant guns, I would crimp.

Crimping swages bullets. For handguns, whatever inherent accuracy loss that causes is more than hidden by my huge aiming error.

For rifles, well lever actions are not exactly match rifles, so I am not going to see the error, and it may keep the bullets from being pushed into the case.

In match rifles, my match rifle bullets are too perfect and too expensive to be squished by an el cheapo crimp die.

This is what a Lee Factory Crimp die will do to 6.5 MM SMK's.

[James R. Burke]

So far rifle wise I do not crimp anything. I would crimp a auto but do not have one. When working up a load for a bolt action I will load up the mag for a couple of resons. Make sure that the c.o.l. is not to long so they feed o.k. and I put a dummie round for the last one and measure it to see if there was any movement. I like to stay on the safe side. Lots of your rifle bullets dont even have a crimping cannelure. The three main rifles I reload for are Ruger No 1's so being a single shot it is not needed, and one is a .416 Rem Mag. For tube feed levers you need to crimp. Probably for all levers. I am sure you will pick up alot better advice on your post.

[gb_in_ga]

For rifles, well lever actions are not exactly match rifles, so I am not going to see the error, and it may keep the bullets from being pushed into the case.

It is true that tube fed lever action rifles aren't exactly match grade rifles, but they aren't all that inaccurate, either. They are accurate enough so that you do have to pay attention to such things, most modern ones in good condition will do better than 1 MOA if fed right. And it is true that you do have to crimp the bullets so they don't get pushed back into the case while in the magazine, under recoil. One thing to keep in mind about bullets designed for tube fed lever actions is that they have cannelures. Just crimp in the cannelure which was designed just for that purpose and the bullet deformation issue goes away.

For tube feed levers you need to crimp. Probably for all levers.

There are vertical magazine fed lever action rifles. Such as the Savage 99, Winchester 88, and the BLR. I've loaded for the Savage 99 and Winchester 88 before. I found that a crimp was no more necessary in those applications than it would have been in a vertical magazine fed bolt action rifle.

[jamaica]

The only rifle bullets I ever crimp are for the 30-30 in a lever action with a tubular barrel. Win 94.

I haven't loaded for autoloader rifles.

I crimp pistol and revolver rounds.

Just because a bullet has a cannelure, doesn't mean you have to crimp it.

[kraigwy]

I dont crimp any rifle cases except heavy loads of black powder that tend to want to push the bullet out of the case. (45-70 & 44-90 sharps bottleneck) both using cast bullets.

I criimp pretty much all my pistol cases excluding my 30 Herritt & 30-30 which I shoot in my TC. (Taper crimp for 45 ACP, 9mm, 380 and such).

[Archie]

One crimps for the following reasons: (Not exhaustive)

* Heavy recoiling revolver bullets to keep them from pulling (like a kinetic bullet puller) in recoil.

* Heavy, slow burning powder loads in some revolver (mostly) or rifle (less often) applications to insure proper ignition and burning. This is normally in addition to a tight neck fit; not replacing properly sized cases.

* Heavy recoiling rifle rounds in either tubular magazines (more common) or box magazines (less common) to prevent bullet set back in recoil. Normally in connection with a cannelure.

* For use in semi-automatic or automatic weapons to prevent bullet set back while being manipulated through the action. Normally in connection with a cannelure.

* Any round requiring belling of the case to seat bullets. Usually just enough to to remove the belling to insure the loaded round will chamber properly.

If none of these conditions apply in your applications, you have no need to crimp.

[smoakingun]

This is what a Lee Factory Crimp die will do to 6.5 MM SMK's.

if your factory crimp die is doing that, you have it set wrong.
tubular magazine, crimp
vertical magazine, no crimp
by not crimping your brass you may extend the life of the brass, every manipilation that streches(bullet seating, neck flaring) or shrinks the brass(crimping) work hardens the brass, making it more prone to spliting/cracking

[Qtiphky]

I load for 204 Ruger, 223 Rem, 30 Carbine, 270 Win, 308 Win and 300 WSM and the only rounds that I crimp are my 223. The 30 carbine is treated like a straight walled pistol case so the die is a taper crimp. The rest are very similar because they are magazine fed bolt actions. I have the accuracy dialed in very good and don't feel that I need to crimp.

I crimp the 223 because the Lee FCD came with the set. I have loaded both ways, crimped and not crimped, and found that the crimped rounds are more accurate with my guns, all autoloaders. This may not be the case with your guns, only you will know as you develop loads.

[kemayfield]

Wow! excellent advice and info, thanks alot. I am loading first for my bolt gun, but plan to move on to my M1 and others. The more I get into this the more things I am learning and it is becoming an obsession. I will be calling Dillon for some clarification on this.

[JFN]

This is what a Lee Factory Crimp die will do to 6.5 MM SMK's.

Actually those are perfect examples of what a poorly adjusted Lee FCD will do. Adjustment ranges from no crimp at all to ridiculous, and yours is obviously cranked down to the ridiculous level.

[Slamfire]

Actually those are perfect examples of what a poorly adjusted Lee FCD will do. Adjustment ranges from no crimp at all to ridiculous, and yours is obviously cranked down to the ridiculous level.

The Lee FCD die will damage bullets, and you can't tell until you pull the bullets.

Match bullets are particularly thin skinned.

I have been squadded with the world's best shooters in the World at Camp Perry. You have time to talk to them when pulling targets.

If the Lee FCD die gave the slightest, the tiny tiniest accuracy advantage, everyone would be using it. No one, and I mean no one, uses the thing on their match ammo.

[Bart B.]

Some 60 or more years ago, the US military arsenals loading match ammo for the .30-06 changed from crimped to non-crimped in bullets. The original 172-gr. FMJ match bullet had a cannelure for crimping. Not running these bullets through the cannelureing machine meant no case mouth crimping was needed. Muzzle velocity spreads got smaller. Accuracy improved as crimping tended to unbalance bullets.

Anybody believing crimped rifle bullets improve accuracy doesn't test them properly; typically not shooting enough rounds for a statistically significant result.

The above aside, if you're shooting 300 grain or heavier bullets from a very big game rifle, then crimping is an advantage. You don't need the best accuracy, but those bullets in the magazine (or the other barrel in a double rifle) need to stay in place with all that heavy recoil going on.

[Sport45]

I don't crimp anything I feed to my AR or M1.

About the only thing I crimp is the heavy lead or magnum revolver rounds.

[rjrivero]

The Dillon Rifle Dies are Taper Crimp Dies. You can put a light taper on it if you wish, or none at all. All of my rounds get a VERY light taper. Pistol rounds get tapered because you must remove the light BELL put in the case for the bullet seating.