9mm RCBS carbide die taper crimp issue

waynewjw

waynewjw

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1st go at reloading 9mm today. PITA! Read the instructions probably 10 times and had a real difficult time getting the proper taper crimp. The bullet, in most cases fit the pistol and would fall out as they should. But every 3rd round or so would only partially fit. And when I closed the action I couldn't open again without pounding the round back out from the barrel end. All cases same length and were unpowdered test rounds. What's the secret?
 
Have you checked the over all length? It sounds like the over all length may be a little too long and the ogive of the bullet is getting jammed against the rifling. Take a couple of the bullets that have jammed and shorten them by .010 or so and see if that helps.
 
dogzilla said:
Have you checked the over all length? It sounds like the over all length may be a little too long and the ogive of the bullet is getting jammed against the rifling. Take a couple of the bullets that have jammed and shorten them by .010 or so and see if that helps.
Click to expand...

This is exactly where I would start. OAL is your problem here, not crimp.

To verify correct OAL, remove the barrel from the pistol, get a few of the bullets and drop them in the chamber. Give them a little push to make sure they're seated all the way and then spin them in the chamber. If the loads are done right, they should spin freely. If you have some factory rounds on hand or a few of those reloads seated at 0.010" shorter like DZ suggests, compare those to what your reloads feel like when you spin them in the barrel. If they are hitting the rifling, that should be a clear indication your OAL needs to be shortened.
 
I usually have no issues when following the OAL of the hornady book.
What oal did you reload which bullets to?

And also, I always use the lee carbide factory crimp die on pistol.
If the round goes through the die, it will fit any chamber (excluding OAL, of course...)
 
If you're loading for a Shadow, they are known for short chambers. I load mine at 1.087 OAL. I kept going shorter and shorter and was wondering what I'd done wrong, but at that length they all started dropping free from the chamber.
 
The case isn't the problem, you almost certainly need to push the bullet back a bit because the copper jacket is hitting the rifling
 
waynewjw

On semi-automatic pistols the taper crimp is "NOT" used to hold the bullet in place, the "crimp" is used to reduce the case mouth flare. You need to measure the outside diameter of the case with the bullet seated and then "taper" the case mouth crimp .002 to .003 smaller than the outside diameter of the case. The taper crimp is used to keep the case mouth from not dragging or snagging when feeding before it is chambered. The sizing and minimum expanding should leave the case tight enough to hold the bullet in place.

I'm using Rainier plated lead bullets in my .44 magnum and I use a taper crimp die to just reduce the case mouth size to .002 to .003 smaller than the diameter of the loaded case. If I crimped any smaller the crimp would go through the copper plating and cause barrel leading.

Check your loaded cases and make sure the cases are not "bulged" just below the crimp, you may be over crimping your cases.

I had a hard time adjusting to the 9mm and .40 S&W cases and re-training myself after reloading for revolvers.

Case length is not critical on these type cases because you are "NOT" using a roll type crimp, you are using a "taper crimp" and only reducing case mouth diameter. The taper crimp does not bite into the bullet and is only used to prevent feeding problems.

I use case gauges because I also load for my sons pistols and don't have his barrel to test my reloaded rounds. The Gauge is at minimum SAAMI case length and diameter and if a case is too "FAT" or "LONG" it will not fit in the gauge.

Below is a fired case and it is too fat to drop into the gauge.



Below is a resized case and it drops into the gauge and will fall out without binding.



Bottom line, a taper crimp is not crimping the case to the bullet, it only resizes the case mouth for proper feeding.

The Lyman type M die patent expired and now Redding and RCBS are using this type case mouth expander. The expander creates a "step" inside the case and flaring the case mouth is not required to seat your bullets. The taper crimp simply sizes this "step" to the outside diameter of the case.

See center die expander below.
 
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I read on another blog where a good test to see if I've got it right is to take a sized case, flare it, and then take the empty case and place it into the taper crimp die. The case dimensions should be the same - before and after. It made sense to me. Thanks for the info BIGEDP51.

I've just been reloading 2-die rifle ammo for the past 3 years, so loading for pistol and revolver is a bit of a challenge, a bit of frustration. I've adjusted the crimp die so many times, reading and re-reading the RCBS instructions. I want to get the 9mm figured out and have the dies set to now reload some volume. The next step will be taking the 38 SP/357 Mag RCBC dies and loading 38SP. In both cases I'm using carbide dies.

Thanks you guy, this info is great.
 
for some reason the lee die is just so easy to use, and it always works. plus the case goes through a carbide ring, and if it goes in, the case goes it the barrel.
I don't know about other brands, but the lee dies have never let me reload a round that would not chamber.
 
The Lee Factory Crimp Die works great with jacketed bullets, "BUT" many cast bullet shooters do not like them because they can "squeeze" the lead bullet smaller than the desired diameter of the cylinder or bore. Bottom line, the Lee Factory Crimp Die can have an adverse effect on cast and copper plated lead bullets by compressing the bullet inside the case to a smaller diameter. This can effect accuracy and cause leading in the bore from the bullet being under sized.

I have the Lee four die set for the 9mm with the FCD and the die works great, "BUT" think about it, the die was created for people who over crimp their cases and the carbide insert is for resizing bulging brass cartridge case.

Bottom line I seat and crimp in two separate operations to avoid bulging cases and the carbide ring never touches the inside of my cases. ;)
 
waynewjw said:
I read on another blog where a good test to see if I've got it right is to take a sized case, flare it, and then take the empty case and place it into the taper crimp die. The case dimensions should be the same - before and after. It made sense to me. Thanks for the info BIGEDP51.
Click to expand...

Go to the Brian Enos reloading forum, Brian is a well known competition pistol shooter. In these forums other competitors give out good reloading advice, you do not want the case mouth the same diameter as the case body. You want the case mouth .002 to .003 smaller so the case mouth will not catch or drag on the when feeding into the chamber.

http://www.brianenos.com/forums/index.php?act=idx

Remember a taper crimp is "NOT" a roll crimp holding the bullet in place, the taper crimps only job is to allow smooth chambering and not let the case mouth hang up and cause a failure to feed. In simple English the taper crimp should make the case mouth very slightly smaller than the body of the case and streamlining the case mouth to insure proper feeding and chambering.

Read the posting below and look at Dale53 photos in his posting

What is the difference between a roll crimp and a taper crimp?
http://smith-wessonforum.com/reloading/162307-what-difference-between-roll-crimp-taper-crimp.html

Again I have a S&W 29 .44 magnum and I have a roll crimp die and a taper crimp die and the taper crimp die is for copper plated bullets that do not have a crimping groove or cannelure. A roll crimp on a copper plated bullet will cause poor accuracy and leading in the barrel. Target loads with fast burning powders do not require a heavy crimp but hot loads with slow burning powders require a heavy crimp to allow proper burning of the powder.



Below, a uncrimped pacemaker. :rolleyes:

 
I'm thinking that my frustration is trying to make the RCBS tamper crimp die seat and crimp at the same time. I've adjusted the settings probably 2 dozen times. I've also checked out a few video's on YouTube. From here I think I will seat the bullets first and ignore the taper crimp in this step. Once I've seated a bunch, I will then set up the taper crimp feature and go from there. If they drop into the barrel, then I think I've got it. If this doesn't work, I'm just going to buy the Lee taper crimp die as this looks fairly straight forward to do.
 
Simply adjust the crimp for a light crimp on lead bullets.
You don't need to overcrimp on the lee FCD.
 
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The best advise from all you guys was to take the seater crimp die and split the process into two separate steps. Step One seat all your bullets. Step Two set the die up to taper (9mm) or roll crimp (38/357). Once I did that, the process was easy. And removing the barrel in the 9mm and having the bullets drop in and fall out easily confirmed that all the steps I followed were right.

Next weekend will see the results at the range.

Thanks for all the help and advise guys, it's appreciated.
 
seat with one die and crimp with the other, that's for sure.
on lead bullets adjust the crimp die to minimal just to remove flaring....
I like lee FCD because any round that goes through it will chamber any pistol. It's like checking all your rounds.
 
bigedp51 you explained this exactly right.

I highly recommend getting a case gauge. the rounds should slide into it and out of it with no friction.
 
How to taper crimp a pistol case
1. Measure the thickness of the case mouth and double the measurement.
2. Measure the diameter of the bullet.

Example: 9mm case wall thickness .012
2 x.012 = .024 + .355 = .379

Minimum taper crimp .379 maximum taper crimp .377, any more than .377 and the case may begin to bulge below the crimp when you seat and crimp in the same operation. The taper crimp "DOES NOT" hold the bullet in place it simply removes the bell\flair at the case mouth and makes the case a uniform diameter so it will not fail to feed or chamber.

If you can push the bullet into the case before you crimp then the expander is too large and needs to be a smaller diameter. I loaded 200 rounds of 9mm last night and one case failed the push test, this was because the case wall thickness was .002 smaller than the other cases and this case went into the scrap brass bucket.

Some good info at the link below.

OAL and crimp questions...(a posting at an American competitive pistol shooting forum)
http://www.brianenos.com/forums/index.php?showtopic=175879&hl=%2Btaper+%2Bcrimp#entry1943983
 
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Finally got out to the range today with the 1st 15 rounds each of 9mm and .38 Special. After all the advise from you guys about seating in one step and then doing the taper or roll crimp as a separate last step, the 9mm were taper crimped, bullets fell in and out of the barrel with OAL's of 1.1 and 1.25. I roll crimped the .38's on the bullet groove and didn't worry too much about OAL.

The .38's fired off pretty smoothly, cases didn't have much powder burn. So I think I'm happy, just need to play with powder to gain accuracy.

The 9mm's, which I loaded in .1 grain increments shot OK but no groups to write home about. I did get a "V" shaped powder burn on one side of each case, which I believe is likely due to seating to short. What do you guys think? This week, with barrel in hand I'm going to do a few dummies to see how they fit and go from there, seating to a longer OAL.
 
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