crimp amount?

[cocopuff]

Being fairly new to reloading hand gun ammo,how do I know the proper anount of crimp to apply..Should have added that these are 44 cal with cast bullets..44 special and 44 mag..

 

[DirtySteve]

None on any of my rifle ammo....

 

[Bc'z]

What cartridge?
Taper or roll?
I use a taper on 45 & 380 auto as the cartridge head space is on mouth of cartridge just enough to firmly hold bullet and not create a bulge below crimp.
45lc I use a roll crimp, cartridge head space is on the rim here.

 

[Uncle Ed]

Being fairly new to reloading hand gun ammo,how do I know the proper amount of crimp to apply..

It can vary with light loads and heavy magnum loads. As a example with light loads with plated bullets in my .44 Magnum I use a taper crimp. But with hot loads in my .44 magnum I use a good roll crimp. I also seat and crimp in separate operations to keep the crimps more uniform.

A taper crimp for semi-auto pistols are used to close up the belling of the case mouth and bullet grip is controlled by how tightly the case grips the bullet.

Below a 9mm cartridge before a taper crimp is applied.

Below the same case after a taper crimp is applied with the case mouth streamlined for feeding. The cartridge is wasp waisted and shows that bullet grip is controlled by how tightly the case grips the bullet. And since these type cases headspace on the case mouth the taper crimp main purpose is to streamline the case mouth for proper feeding.

Another example below is the RCBS AR Series dies, this .223 die has a taper crimp. And the taper crimp main purpose is to streamline the case mouth for proper feeding in AR15 type rifles.

 

[Twicepop]

When I first started "rollin" my own" pistol ammo I tried to seat and crimp in the same step. It was never totally successful, and if there was any kind of a bullet change, everything had to be re-set. Once I started crimping as a separate step, the feeding (for autoloaders), functioning and the appearance of my ammo improved. For roll crimping revolver ammo, case length is a critical factor to get consistent crimps. For heavy loaded revolver ammo that get what is called a neck-down crimp, case length isn't as critical, but should probably kept withing about plus(+) or minus(-) .010" your target length. For auto pistol ammo that gets a taper crimp, case length isn't critical unless your shooting in a scored match with a target grade gun.

 

[SSL]

Being fairly new to reloading hand gun ammo,how do I know the proper anount of crimp to apply..

Set your seating die to only seat the bullet to the proper depth. Switch to a Lee Factory Crimp Die for final crimping. Follow their directions and you should be fine. Seating and crimping in one step will usually shave bullet material as the bullet is seated while the case mouth is being closed for the crimp.

 

[Uncle Ed]

The lee factory crimp die with a carbide ring in its base is a cheat for reloaders who do not trim their cases to the same length. Meaning the longer cases can bulge below the crimp, the carbide ring in this Lee die will size down any crimp bulge. This same die will also size down oversized cast bullets in its carbide ring.

That being said I have this same Lee die for all my handguns but you need to know this dies limitations. And if you shoot oversized cast bullets or coated bullets this die may do more harm than good. I trim all my revolver cases to the same length and buy cast bullets that are sized to my cylinder throat diameter. And this Lee factory crimp die can size these cast bullets smaller in diameter if the carbide ring post-sizes the cartridge again.

Below the lee factory crimp die with a carbide ring in its base.

 

[SSL]

True - very good point. I use a spare standard seating die with the seating stem removed to crimp cartridges for one of my .44 Magnums that requires an oversize cast bullet to prevent leading. The body of the standard die is generous enough to prevent that final "squeeze" on the bullet diameter. The rest of the handguns I reload take more standard cast bullets (.358", .430", .452" and .454") and are not affected by that final sizing provided by the appropriate Lee die.

 

[243winxb]

44 cast. Sear bullet to your COL without crimping.. Back seating stem/plug, out/up so it doesnt contact the bullet.
With loaded round up in ram, turn crimp die down by hand, hard. When you can no longer screw the die down any more, you have a perfect crimp.

Neck tension keeps bullets from jumping crimp, more then the crimp. A 357 will have about .002" neck tension. The 460 s&w about .004"

 

[pirate ammo]

@Uncle Ed and @SSL have you going the right way, separate step for crimping.

 

[Rsadams]

Being fairly new to reloading hand gun ammo,how do I know the proper anount of crimp to apply..Should have added that these are 44 cal with cast bullets..44 special and 44 mag..

Since your talking about handgun ammo that is roll crimped I apply a pretty decent one.... You can start light and work up to more crimp to find the correct amount... Fire a few and pull the last round out of your pistol and measure it or look for unburned powder if your not seeing any and your not getting bullet jump from recoil your good.... You should have plenty of neck tension if your dies are setup per manufacturers directions.... Also I crimp in a separate step with the Lee factory crimp die and have zero problems with it over thousands and thousands of .38 spl rounds.... That way you don't have to keep adjusting your die back.... Plus I do either group after re-sizing or trim my pistol brass to all one length or pretty darn close...

 

[cocopuff]

So tell me,how much is accuracy effected by crimp..I fired a few loads and got some black cases..Would to light a crimp have caused this??And too heavy would possibly effect the cast bullet..????/
like deform it, change pressure and velocity..i gotta get my chronograph out...plus shorten case life...

 

[Twicepop]

The lee factory crimp die with a carbide ring in its base is a cheat for reloaders who do not trim their cases to the same length. Meaning the longer cases can bulge below the crimp, the carbide ring in this Lee die will size down any crimp bulge. This same die will also size down oversized cast bullets in its carbide ring.

That being said I have this same Lee die for all my handguns but you need to know this dies limitations. And if you shoot oversized cast bullets or coated bullets this die may do more harm than good. I trim all my revolver cases to the same length and buy cast bullets that are sized to my cylinder throat diameter. And this Lee factory crimp die can size these cast bullets smaller in diameter if the carbide ring post-sizes the cartridge again.

Below the lee factory crimp die with a carbide ring in its base.

I use those LEE FCDs for my auto pistols that I reload for, not quite for the same reason(s) in your post. I use them because the carbide ring irons out the last vestiges of case bulge on the range brass I almost always use. For revolvers my dies are all RCBS with carbide sizers, for crimping I purchased extra bullet seating dies and removed the bullet seating stems and use them only for the roll crimp they have built in.

 

[SSL]

CocoPuff - Depending on the firearm (revolver, semi-auto, etc.) you can expect smoking to some extent or another with most all handguns. This is due to the fact that handguns are notably inefficient at sealing chambers when the brass expands upon ignition and some powders just plain burn dirty. The crimp has little to do with this other than when using slower powders that require heavy crimps to allow more efficient burning (2400 which should always use non-magnum powders, H110 and W296, both of which generally work best with magnum primers, and the like). The crimp is more to keep bullets from either being pushed back into the case, causing severe pressure spikes, or working forward under recoil to jam up the cylinder (revolvers) or end up jammed into the lands (Semi-autos) again causing pressure spikes.

 

[Rsadams]

So tell me,how much is accuracy effected by crimp..I fired a few loads and got some black cases..Would to light a crimp have caused this??And too heavy would possibly effect the cast bullet..????/
like deform it, change pressure and velocity..i gotta get my chronograph out...plus shorten case life...

A good roll crimp will help you get a better burn , just that few micro seconds matter.... I ran into that problem with the wife's down loaded.38 spl , it's a very light gun ( Ruger LCR ) and I don't even like shooting a box through it of full power loads... The powder I use ( win 231 ) becomes very position sensitive and a better crimp really helped and was suggested by many members... What I like to do is take an empty case , no powder or primer and put a quarter turn then pull that bullet... Then a half turn and pull , then 3/4 and pull and finally a whole turn and pull the bullet so I can see the amount of crimp... So I waste a few bullets but learn exactly what the crimp looks like.... Like I said I use the Lee factory crimp die for almost all my crimping needs and it takes ALOT more crimp than you think to screw up accuracy.... Don't be scared to load a few groups of 5-10 with different settings and find out exactly what works for you.... Experimenting is part of reloading , just be safe while doing it.. As far as case life they will live a long time for pistol , to me they start getting hard long before they split or if you're hotting them up they stop holding the primer tight... We can give you a bunch of advice but you have to figure out what your gun likes.... Yes you need to get your cronograph involved....

 

[AJC]

I use rcbs dies for my pistol reloads. The carbide is nice and I dont lube. I screw the seating stem all the way in and rotate the die body to set seating depth. After all bullets are seated I pull the stem and lower the die for crimp. Before doing it this way I shaved some bullets and put a lot of marks on my bullets. I dont see a reason to use a lee die to fix bulges because you should fix the problem making the bulges. Ignoring a problem in your process will bite you eventually. A case guage will help you identify problems easily when used often while you iron out your process.

 

[cocopuff]

I really appreciate all of your replies..I have learned a great deal here..Thank
you all very much..And have a safe happy holiday..John