Crimping for 9mm

[la5676]

One of the problems with Lee's FCD for semi-auto cartridges is when too much crimp is applied, the reloader doesn't see the results. Most often too much taper crimp results in a case bulge. So, when there is too much crimp is applied and the case bulges, the bulge is hidden, swaged down, by the sizing ring as the cartridge is removed from the die, but the screwed up neck tension and or distorted crimp remains.

You can accomplish the same overcrimping with a taper crimp die. If not adjusted right, you can almost make a 9mm loaded round look like a 357 Sig round. If one follows the directions on an FCD die, it's pretty hard to screw it up. The same can be said for any die. Ya gotta be smarter than what you are working with. I know people than can tear up an anvil with a rubber hammer. There is nothing wrong with the LEE FCD die if used correctly. Likewise for the TCD. I have both, but use the FCD die way more often, and have no issue with it whatsoever.

[Taterhead]

Is increased taper crimp the cause of greater pressure? No. In fact it can reduce pressure br wrecking the interference fit (neck tension) from excessive crimping.

Brass is springier than lead. So when the case mouth is squeezed by the die, the soft lead underneath swages down some. The brass springs back.

There is an experiment that will demonstrate this. Take an unsized and fired auto-loader case. Place a bullet to the normal depth. Might need a filler underneath to keep the bullet from falling in. At this point there is zero neck tension.

Gradually add more and more taper. Note that even an excessive crimp will barely keep the bullet from easily plopping out with a light blow from a kinetic hammer. Typically the bullet can be spun around by hand. The taper crimp die just doesn't do much for bullet pull. It can make a mechanical step to prevent setback, but that is a different mechanical process than creating bullet pull.

[fn1889m]

I have never experienced that but I suppose it could happen.
But some of us can screw up a crimp with any brand die on occasion .

Yep. I have overcrimped 9mm. It does bulge the case. I have also dented an anvil. It takes some time to learn that less is often better in fly tying and reloading.

[robg]

a light load can cause primers to back out if the pressure is low as the case can move about.

[onelight]

a light load can cause primers to back out if the pressure is low as the case can move about.

This is true , but I can't imagine a load light enough for this to happen that would cycle an auto pistol.

[1006]

I have had 3 different Lee Carbide Factory Crimp dies cause the same problem. 357, 45 Colt, and 9mm. They “Coke Bottle” the case with the sizing ring located in the bottom of the die. In the 9mm it actually squishes the bullet as it goes over it and pushes it out slightly, causing my COL to increase, kind of like shooting a watermelon seed by squeezing it between your thumb and finger until it pops out.

I have better results with traditional simultaneous, one step seat and roll crimp operations, and SEPARATE, two step seat and taper crimp operations.

People were reloading very successfully for a long time before the Lee Carbide Factory Crimp Die came out. I usually do not use them for pistols. I do like the Rifle Die, Lee Factory Crimp die for lightly crimping the case mouth back down after seating bullets that required a slight case mouth flaring before seating the bullet.

I like Lee Dies, just not the Carbide Factory Crimp Die pistol dies.

[1006]

Regarding the primer intrusion: you did not say what type of gun you are shooting, and it is hard to tell, without a picture, what you are having happen.

But, in addition to the things already mentioned, your gun may be unlocking just the smallest amount after primer ignition and firing, causing the firing pin to drag on the primer as the bullet begins to eject. Several things can help prevent this: replace the gun’s firing pin retraction spring if it is a hammer fired gun, replace the recoil spring with a heavier one if you have a striker fired gun. If the indent left in your primer looks elongated or teardropped try changing the springs.

[fredj338]

I doubt your crimp is affecting pressures much, unless you were already running max but still not likely imo. Just crimp enough to remove the flare. If you are denting the bullet, it is too much & can play havoc with accuracy.

[onelight]

I have had 3 different Lee Factory Crimp dies cause the same problem. 357, 45 Colt, and 9mm. They “Coke Bottle” the case with the sizing ring located in the bottom of the die. In the 9mm it actually squishes the bullet as it goes over it and pushes it out slightly, causing my COL to increase, kind of like shooting a watermelon seed by squeezing it between your thumb and finger until it pops out.

I have better results with traditional simultaneous, one step seat and roll crimp operations, and SEPARATE, two step seat and taper crimp operations.

People were reloading very successfully for a long time before the Lee Factory Crimp Die came out. I usually do not use them for pistols. I do like the Rifle Die, Lee Factory Crimp die for lightly crimping the case mouth back down after seating bullets that required a slight case mouth flaring before seating the bullet.

I like Lee Dies, just not the Factory Crimp pistol dies.

I have six sets with carbide factory crimp dies my revolver dies the carbide ring does not size anything I can push a fired case unsized case into it with finger pressure unless Lee has changed them something is wrong with yours.
My auto pistol dies do bump over a cast bullet they make the cartridge the same size as a factory load That is what it is designed to do. If you want over size ammunition it is the wrong die .

[Dapaki]

I hate to ask but have you measured the COL?

[Carrier]

I use FCD on every handgun I reload for. What I did for loading lead is have a FCD I knocked the ring out of so the case enters the FCD with no interference with over sized flat base bullets so the ring doesn’t swage the bullet. I like them for the simple fact of being able to adjust so much easier.
Am I a hack I don’t know but it works for me.

[Taterhead]

For the benefit of any new loaders tuning in, it would be useful to be specific when we're referring to the

"Factory Crimp Die": the tool that applies a crimp using a collet crimping mechanism

Vs

"Carbide Factory Crimp Die". This is a completely different tool that has a carbide sizing ring in the die mouth to "iron out" or post size any irregularities or high spots on the case. I will spare my thought on this controversial feature. The crimping insert might be either a traditional roll or taper, as the case may be. This tool does not use a collet.

Similar name. Completely different tools.

[onelight]

For the benefit of any new loaders tuning in, it would be useful to be specific when we're referring to the

"Factory Crimp Die": the tool that applies a crimp using a collet crimping mechanism

Vs

"Carbide Factory Crimp Die". This is a completely different tool that has a carbide sizing ring in the die mouth to "iron out" or post size any irregularities or high spots on the case. I will spare my thought on this controversial feature. The crimping insert might be either a traditional roll or taper, as the case may be. This tool does not use a collet.

Similar name. Completely different tools.

It is confusing that Lee calls them both factory crimp dies , I like and use both two more tools in the tool box .
The carbide crimp is for duplicating factory spec outside dimensions these will function in any gun just like factory assuming proper bullet choice and OAL if you need or want custom oversize ammunition it is the wrong die.
The collet die is a completely different product uses a collet to make the crimp , and to add to the confusion they also have collet sizer dies

[Burnt Fingers]

For the benefit of any new loaders tuning in, it would be useful to be specific when we're referring to the

"Factory Crimp Die": the tool that applies a crimp using a collet crimping mechanism

Vs

"Carbide Factory Crimp Die". This is a completely different tool that has a carbide sizing ring in the die mouth to "iron out" or post size any irregularities or high spots on the case. I will spare my thought on this controversial feature. The crimping insert might be either a traditional roll or taper, as the case may be. This tool does not use a collet.

Similar name. Completely different tools.

Many people get the two confused. I have no problem with the factory crimp die. I use a couple of them myself. However the Carbide FCD causes more problems than it solves. Even more when it's used on cast boolits that are oversized.

[Carrier]

Many people get the two confused. I have no problem with the factory crimp die. I use a couple of them myself. However the Carbide FCD causes more problems than it solves. Even more when it's used on cast boolits that are oversized.

Just have to knock the ring out if it does.

[onelight]

Many people get the two confused. I have no problem with the factory crimp die. I use a couple of them myself. However the Carbide FCD causes more problems than it solves. Even more when it's used on cast boolits that are oversized.

It does does what it is designed to do ,what causes a problem is when some one uses the wrong tool for the what they want to accomplish .

[GONRA]

GONRA runs all 9mm and .45ACP reloads thru LFC dies. (Load lottsa jacketed boolits.) Just make SURE all yer reloads PASS THE PLUNK TEST!
OVERSIZE Cast Lead boolit reloads - may NOT "pass the plunk test" or result in bulged cases, etc. so watchout.....

[WheelgunConvert]

Only for 9mm, I use a spacer cut from an old credit card (or similar) and set the gap between the shell holder and the carbide FCD. Then adjust the taper screw for a light crimp per directions. Because the Luger case is tapered, it will engage the carbide ring if the case is significantly larger but otherwise will not swage the projectile or cartridge. YMMV.

[megasupermagnum]

Only for 9mm, I use a spacer cut from an old credit card (or similar) and set the gap between the shell holder and the carbide FCD. Then adjust the taper screw for a light crimp per directions. Because the Luger case is tapered, it will engage the carbide ring if the case is significantly larger but otherwise will not swage the projectile or cartridge. YMMV.

But the carbide sizing ring isn't tapered, so what does that gain you? It's still sizing over the bullet.

For the record, I never once had a problem with the carbide sizers. .002" over sized cast bullets still do not size down in any carbide FCD I've tried. If it does, it's a simple task to smack the ring out of the die.

[cupajoe]

I was recently gifted a Lee Deluxe Pistol Die Set in 9MM Luger. A renter had left some reloading gear when he moved. This die set has the carbide factory crimp die. The carbide ring IS indeed tapered. .394 at the mouth and .381 in as far as my calipers will freely reach. I don't have any idea how well they work as I don't use a taper crimp. I don't know if these are older or newer dies or if all carbide taper crimp dies now are tapered.