Lee FCD and neck tension

[jim8115]

I have heard that the FCD will resize lead bullets, but have never pulled any to test that theory. What I did just discover, is that it will loosen the bullets. I had loaded some coated lead bullets, and used the FCD. I put one on the bench and was able to push the bullet deeper by hand. Took a fair amount of force, but less that I would expect. Ok, so I took 3 of the same that I had loaded without using the FCD, and could not push them any deeper by hand. Took those cartridges, ran them through the FCD, and was able to push one deeper. This proves to me that the FCD can loosen the bullet in the case, probably depends on the brass. But I wont be using it anymore, especially for the 40, where bullet setback can cause problems.

JIM

 

[padd54]

Can't you adjust the die to give you more crimp? The ones that I use allow me to.

 

[jim8115]

I could add more crimp, but I dont think that is the answer

 

[GLOOB]

Can't you adjust the die to give you more crimp?

Wouldn't that be burning your coat to keep warm?
If crimp is what you're after, why not use a regular seating/crimping die?

 

[GT1]

The FCD behaves just like a taper only crimp die unless the brass is out of spec, in which case the sizing ring will contact the brass.
So, either the brass is out of spec, or the bullets are oversize(Which is the norm for most lead bullets, coated or not). The lead bullet thing has been discussed a bunch, sometimes the FCD hits it, sometimes not, there are so many variables.

I'm going to guess it is the latter.

 

[Lost Sheep]

I could add more crimp, but I dont think that is the answer

Quite right. More crimp is likely to mess up headspacing on your 40 S&W cartridges (and all cartridges that headspace on the case mouth).

It is the post-sizing that reduces the case tension.

padd54, are you using Lee's Rifle FCD, Lee's Pistol FCD or a crimp die from some other manufacturer? The difference is significant.

Here are some dicussions that I believe are worthwhile to read, especially Iowegan's comments in the thread on Rugerforum.net (the last on in the list)


Not necessary 99% of the time, but convenient.

One thread contains a lively discussion of the FCD and the function of the post-sizing carbide ring in the FCD. The phrase "9mm" is in the thread title, but don't let that dissuade you. It contains responses direct from Lee Precision, too. Read the whole thing. It is worth it.
http://thefiringline.com/forums/showthread.php?t=465091

this thread contains a poll

http://thefiringline.com/forums/showthread.php?t=465603

The Virtue and the Vice
http://thefiringline.com/forums/showthread.php?t=509934
http://www.thehighroad.org/showthread.php?t=691050
http://www.rugerforum.com/phpBB3/viewtopic.php?f=11&t=168362

http://rugerforum.net/reloading/65863-lee-fcd-pistol-not-rifle-virtue-vice.html#post814465

Lost Sheep

 

[chris in va]

My FCD reduces my 9mm back to SAAMI, as evidenced by the shiny rings on the case. It doesn't touch my 45 though.

 

[jjjitters]

This is what so many people just can't realize the fcd can and will do. I think it is a good die for jacketed(when reliability is paramount) and such but it is a big question mark for use with lead. It would probably help if Lee made them all to the same specs from die to die, I suspect if you take ten of them, same caliber, you'll get almost ten different inside dimensions, albeit maybe +/- .001" maybe, cylindrical ground items should be closer tolerances.

 

[steve4102]

Remove the crimp feature from the die.

Test a loaded round for neck tension.

Run it through the FCD without applying any crimp.

Test tension again.

If tension is less, then you know that the carbide ring is the culprit. If tension is unchanged then you know you have a problem with the way/amount of actual crimp you are applying and the carbide ring is not the issue.

 

[LiveLife]

+1.

To test neck tension, measure the OALs before and after feeding/chambering the test round from the magazine and releasing the slide.

I found my old method of pushing the bullet against the bench top to be inadequate for determining neck tension - Caliper measurement of OALs is more precise. Even when I thought I "felt" no bullet movement when I pushed on the bullet, caliper measurement showed a decrease in OAL that I could not see.

 

[longdayjake]

If most die sets come with a seat/crip combo die, then what is the purpose of the LFCD?

 

[RustyFN]

If most die sets come with a seat/crip combo die, then what is the purpose of the LFCD?

To separate the seat and crimp operation. Not everybody likes to seat and crimp at the same time.

 

[jim8115]

I wasnt asking a question, or looking for a solution, as I can just seat / crimp in 2 steps with the lee seat / crimp die. I was just making an observation, and passing it on....

JIM

 

[david_r]

Can't you adjust the die to give you more crimp? The ones that I use allow me to.

You would want less crimp. Try this. Stick your finger (the bullet) in a spring (the case). Smash it with a hammer. The spring is still the same size but clearly it squished your finger.

Whoever suggested removing the crimp portion and testing is on the right track. Although with the 40 being straight wall, I would think to test you could just run the loaded round far enough into the FCD so that the bottom ring resizes below the bullet if that is what is happening. If the ring isn't the problem, try adjusting for less crimp.

 

[Lost Sheep]

+1.

To test neck tension, measure the OALs before and after feeding/chambering the test round from the magazine and releasing the slide.

I found my old method of pushing the bullet against the bench top to be inadequate for determining neck tension - Caliper measurement of OALs is more precise. Even when I thought I "felt" no bullet movement when I pushed on the bullet, caliper measurement showed a decrease in OAL that I could not see.

To really test tension make a tool like the one described in post #3 here
http://rugerforum.net/reloading/65863-lee-fcd-pistol-not-rifle-virtue-vice.html#post814465

Lost Sheep

 

[Lost Sheep]

If most die sets come with a seat/crip combo die, then what is the purpose of the LFCD?

RustyFN gave half the answer. The PRIMARY purpose of the FCD is the same as every other maker's Factory Crimp Die (also called Profile Crimp Die). To apply a crimp and only a crimp. This avoids the problem of applying a crimp at the same time as seating a bullet. Seating and crimping at the same time necessarily involves crimping on a moving bullet which is not helpful to good, clean crimps or uniform seating depth.

Know that crimp does not supply very much grip on the bullet. Friction with the case neck does much more. This holds the bullet from being forced deeper in the case as well as provides for proper pressure buildup during firing. This friction depends greatly on the springiness of the brass on the sides of the bullet.

The secondary function (and the one usually most controversial) of Lee's Factory Crimp Die is to resize the cartridge. The reason Lee believes this is valuable is to ensure feeding/chambering reliability. If an oversized bullet or thick case walls or an off-center seating of a bullet forms a cartridge that will no longer fit into a SAAMI-specification chamber, the sizing function (post-sizing) of the FCD reshapes the cartridge into conformation with SAAMI specs. See Lee's frequently asked questions (FAQ) site.

Unfortunately, this post-sizing of the cartridge SOMETIMES squishes the bullet inside the case. Since lead springs back less than brass, the brass's grip on the bullet is often lessened. This phenomenon is worse with lead bullets than plated and least with jacketed bullets.

http://leeprecision.net/support/ind...-be-used-to-seat-bullets-and-adjust-the-crimp

But don't read just that one. There are several answers to questions that have been asked and hinted at here.

Note: While Lee's instructions included with some of their products are less that optimally helpful, most of their FAQ answers are very good. Use them.

Lost Sheep

 

[beatledog7]

As I read the prevailing wisdom, and in my experience, no sort of crimp from any sort of crimp die ever enhanced neck tension.

Choosing appropriate brass/bullet pairings, properly using a good sizing die, and not over flaring the case mouths assures good neck tension. Crimping never will.

 

[Lost Sheep]

As I read the prevailing wisdom, and in my experience, no sort of crimp from any sort of crimp die ever enhanced neck tension.

Choosing appropriate brass/bullet pairings, properly using a good sizing die, and not over flaring the case mouths assures good neck tension. Crimping never will.

But it is hard to dispel the myth. You can SEE a roll crimp. A lot harder to see friction.

Lost Sheep