Tapper crimp seating die question

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Rushthezeppelin

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First of let me preface by stating that I'm brand speaking new to reloading (twisted up my first one last night). I have done a fair amount of research leading up to this so I'm not running completely blind. I have read my Lee reloading book over the last few days.

So I'm on a Lee 1000 Pro setup for 9mm Luger with Lee dies for sizing/decapping and powder drop/neck expansion but opted for the tapper crimp seating die from RCBS for the last station.

I get my 4.4 grains of W231 throwing consistent in the .46 cavity on the auto disk. Get the expanding die down on the shellplate and backed off a full turn as recommended to get a 3/8" deep flare. Get to the last station and throw on a Berry's 124gr copper plate round nose (I have a CZ clone that loves that weight). Get the seating die to produce OAL of 1.101".

I then go to set the crimp die and as I was holding the press up and screwing the die down my hand on the lever slipped and caused me to turn the die possibly as much as a full turn and I subsequently get back on the lever and set that crimp.

Doesn't appear to be any bulging of the case, seems to have a uniform taper all the way to the head. Right at the rim is measuring .377".

Allot of back story for my question I know but I like to cover my bases, especially with anything firearms related.

So my question is, did I over crimp or is my first round safe to fire?



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without a pic it's impossible to give you a good answer.

Does it fit in your gun?
You didn't say, but it sounds like a 9mm.
Will it give you a nice "plunk" sound if you drop it in your barrel??

Why crush it?
Pull it apart if nothin else & re-use the powder & primer.
 
Right off the bat, your bullet is seated too deep, and your ogive curve is already inside the case mouth.

Next, 3/8" deep flair or expansion is too much.
Back off so you can just barely start the bullet in the case.
The 9mm needs all the case neck tension it can get to prevent bullet set-back during feeding, so don't expand any more then necessary to get the bullet started in the case.

1.101" is too short for a 124 grain RN bullet.
Set the OAL to about 1.140" or so and do a 'Plunk Test' in your chamber to insure the bullet ogive is missing the rifling.

Lengthen the OAL, and set the taper crimp so the case mouth measures .376" and all will be good in the world of 9mm loads.

rc
 
Here is how I set dies quick and easy

1) remove barrel from your gun
2)with the shellplate on the ram and the ram all the way up, screw down your sizing/decap die until it just kisses the shellholder.
3) next with a casing in the shellholder, raise the ram all the way on the next empty spot. screw down your powder through/expander die until it hits the case mouth and stops. then back the shell out and give it another 1/8th turn. this should be just enough to get the bullet to sit on the case
4)send that casing back through the sizing die to get rid of that flair and go to your next station for your bullet seating/crimp
5)raise the ram, unscrew your seater plug until its just about out and then screw down your crimp/seater die down until it hits the case mouth. This is the setting you will need to just get the flair out and nothing more.
6)flair the case out again in your expander die and then roll on to the next die, slowly seat a bullet deeper and deeper checking in between adjustments until the round passes the "plunk test" where it will freely drop in the barrel(PLUNK!) and freely fall out.

save that dummy round to make die setup a bit easier and keep a reference around. once you get used to it, it takes all of two minutes to get your dies set from scratch.
 
rcmodel said:
Right off the bat, your bullet is seated too deep, and your ogive curve is already inside the case mouth.

Next, 3/8" deep flair or expansion is too much.
Back off so you can just barely start the bullet in the case.
The 9mm needs all the case neck tension it can get to prevent bullet set-back during feeding, so don't expand any more then necessary to get the bullet started in the case.

1.101" is too short for a 124 grain RN bullet.
Set the OAL to about 1.140" or so and do a 'Plunk Test' in your chamber to insure the bullet ogive is missing the rifling.

Lengthen the OAL, and set the taper crimp so the case mouth measures .376" and all will be good in the world of 9mm loads.

rc
Click to expand...

Sweet I kinda figured I went to far but read some others talking about using that oal. I know I won't have a problem running into my rifling if I go longer, I did the spent case with bullet barely seated and thrown into my barrel and the oal came out so long I couldn't begin to fit it in my mags. I will try 1.140" next time I sit down and have some more brass to load (going to a multi gun match this weekend and supposedly hardly anyone that attends reloads so I'll have tons of brass soon). Really wish the Lee book had listed w231 for 124gr plated rn so I didn't have to rely on Google searches for oal. Is there a max oal I should adhere to with my powder choice (I've read too much empty space can cause a variety of problems sometimes)?

How much of a turn on the tc die should I use after I have case mouth contact? Lee says a half turn on most dies is a light crimp, what have been people's experiences on the RCBS die?

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(I've read too much empty space can cause a variety of problems sometimes)?
Click to expand...
Only with black powder.
Fuggedaboutit with smokeless powder.

Not Enough air space from seating too deep is a far more serious concern with smokeless power.

How much of a turn on the tc die should I use after I have case mouth contact?
Click to expand...
It's impossible to tell you that.
Use your dial caliper to measure the case mouth of the completed crimp like I said earlier.

The .376" case mouth measurement is all you need to know about how many 'turns' it takes.

'Turns' are curious & meaningless things when you factor in different case mouth thickness among various brands of brass.

The desired result of the taper crimp is only to straighten out the case mouth bell, and have the inside of the case just 'kiss' the bullet jacket.

Taper crimp has nothing to do with 'crimping' the bullet in place.
Only correct case neck tension when you seat the bullet does that.

rc
 
Rushthezeppelin,
Unless you trim your brass to the same exact length as in the load manual and use the same exact bullet the OAL is practically useless to you. It only tells you what the OAL is for the ammo they made.

When I load semi-auto ammo I usually make the round as long as possible out to the Max OAL. As long as it still fits in the magazine and doesn't hit the rifling and it passes the plunk test, you're good to go. I don't try to go short, I go long...
 
Your OAL is mighty short for the Berrys 124 RN. 1.12-1.135 would be my choice range.
I shoot many thousands of the Berry's 124 gr bullets.

A .377"-.378" taper crimp just below the case-mouth is good for the plated .356" bullets.
It won't damage the plating and will feed smoothly in most any chamber.

That bullet will feed in even the tightest CZ/XD chambers with no problem if it fits in the mag.
 
When working with pistol cartridges, and certainly 9mm, longer oal is the proper apporach, as pressures can, and will go excessive when seating deeper than necessary.
Where did you get the pparent idea that a 3/8" bell below case mouth would be a guide. Bell only as much as it takes to seat without shaving the projectile and no more than that. 9mm is one of those rounds that neck tension means everything, and over belling defeats neck tension, as does over crimping.
Once you've finished a round give it the "plunk test" meaning it should make a good solid plunk sound thwn dropped in the barrel, and should fall back out by gravity alone and unassisted.

GS
 
gamestalker said:
When working with pistol cartridges, and certainly 9mm, longer oal is the proper apporach, as pressures can, and will go excessive when seating deeper than necessary.
Where did you get the pparent idea that a 3/8" bell below case mouth would be a guide. Bell only as much as it takes to seat without shaving the projectile and no more than that. 9mm is one of those rounds that neck tension means everything, and over belling defeats neck tension, as does over crimping.
Once you've finished a round give it the "plunk test" meaning it should make a good solid plunk sound thwn dropped in the barrel, and should fall back out by gravity alone and unassisted.

GS
Click to expand...

Misread the expander die, it's talking about the expander inside the die has 3/8" travel room. I did set it up as per instructions, down to shellplate and back out a full turn, I'll do before and after measurements with this die so I can tailor it to the seating depth of the bullet.

Thanks for the advice and also practical reasoning. The mechanics of how this cartridge works are becoming quite a bit more clear.

Sent from my Nexus 7 using Tapatalk 4
 
Think I've finally got it figured out now. After die adjustments i ran a 10 batch through and noticed something that concerned me at first until I did research. Apparently I nailed down the coke bottle shape (which seems to be more common with the Berry's I'm using) that pretty much guarantees I won't have setback. Cranked out another 20 and got more of the same. OAL varied from about 1.145-1.155 (the factory stuff I shot today was about 1.155 and it feed dandy). I think the variation is due partly to the fact my turret is somewhat loose fit not to mention I'm not sorting or trimming. Mouth measurements were consistently .336-.337. No sign of shaving my bullets, granted I don't know what to look for but I assume you will see copper shavings/peelings if I'm doing this.

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Don't worry about trimming 9mm brass. Few straight walled cartridges need trimming.

Thats correct, you will see shavings or crushing a portion of the case mouth. It will feel different when seating the bullet compared to a good seat.

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My bullet is getting scratched pretty good, with no actual "shavings" present. Zat ok?
 
Misread the expander die, it's talking about the expander inside the die has 3/8" travel room. I did set it up as per instructions, down to shellplate and back out a full turn, I'll do before and after measurements with this die so I can tailor it to the seating depth of the bullet.
Click to expand...

That's not a good way of adjusting the expander. You should adjust it so that the case mouth is flared barely enough to allow the base of the bullet to squeeze by.
 
Potatohead said:
My bullet is getting scratched pretty good, with no actual "shavings" present. Zat ok?
Click to expand...
If it were me I would add slightly more flair because there's no guarantee all the bullets will be the same and some that are slightly wider can and will shave. BTW, if a plated bullet shaves there will be no doubt it's happening!
 
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Using a deburring tool to break the sharp inside edge of the case mouth will help a bunch with shaving too.

rc
 
918v said:
Misread the expander die, it's talking about the expander inside the die has 3/8" travel room. I did set it up as per instructions, down to shellplate and back out a full turn, I'll do before and after measurements with this die so I can tailor it to the seating depth of the bullet.
Click to expand...
That's not a good way of adjusting the expander. You should adjust it so that the case mouth is flared barely enough to allow the base of the bullet to squeeze by.
Click to expand...
Exactly what I was going to post.
 
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