Problems trying get proper crimp in 9mm

Status
Not open for further replies.
Dudedog said:
You said you had a 20 hole case. Did you mean a 20 hole case guage?
Wondering if maybe the guage is just on the "tight" side.
If it is one from Shockbottle, they usually run a bit loose...I'm using a 100 round one.

Loaded rounds that won't quite make it in my Wilson will "pass" when dropped into the 100rd one. But it is a good idea to clean them out now and then if you're using lube on your cases...I just use alcohol
 
It is a Double Alpha 20 round case gauge that I'm using.

So I tried going about this a different way. I backed off my crimp die and I ran it down until it just touched a resized case. I then ran empty cases with no bullets through my Dillon XL 650. Resize, bell, seating (no bullet though) and crimp and dropped them in the gauge. Of course they all sat high because there was still belling on the case (average mouth size was 0.385). So I ran the crimp die down a tiny bit and and ran 20 cases and checked them in the gauge. I repeated this with batched of 20 until almost all 20 cases plunked nicely in the gauge (3 had the head protruding slightly) with no bullet seated (average mouth size was 0.377).

I'm thinking this told me the minimum crimp needed to pass the gauge and excluded any bullet seating issues from the equation. I then proceeded to seat bullets in those same cases and tested them again (average mouth size was 0.379). 15 plunked fine and now 5 were sticking up slightly. Not too bad. I started pulling bullets and each an every one had a deformed base like my picture earlier.

To my mind that is telling me there is literally no way to make them pass the gauge without that much crimp. Unless I am missing something. I realize I am a noob, but I am confused.
 
The problem is when I do that it leaves a well defined impression on the base of the bullet when I pull them to check.
Why are you pulling the bullets? If they fit your magazine, chamber (proper "plunk") and shoot the way you want them too what else are you looking for?

The only crimp I apply is a taper that does little more than remove case flare. I do that in a separate operation and depending on bullet diameter shoot for .001"-.002" less than spec.

As already stated, the only case gauge that really matters is your gun's chamber.
 
I'll let you in on a secret. You can't load generically "good ammo" using cast bullets. You can load exceptional ammo for specific guns. But you can't load cast bullets that will chamber and shoot great in all guns. If that's your goal, you are going to fail, period. Some chambers are cut too tight relative to the bore to ever shoot cast bullets worth a darn. OTOH, some chambers and/or throats are cut so big that cast loads will always be smoky, because the casemouth and/or bullet can't completely seal the gases fast enough.

Crimp only enough to get the bullets to chamber in your guns. And if that's not enough to remove the crimp rings, start sorting out your cases to remove the thicker brass. And if that's not enough, shoot them with the excessive crimp rings and see what happens.

Yes, those crimp rings ARE a problem. Potentially a huge problem. If that's the minimal crimp it takes to get rounds to chamber, there's no room for the crimp to open back up when the round is fired. That little ring is just the tip of the iceberg. The entire bullet behind that ring is going to be swaged down that small, too.

That said, the crimp groove is always going to look deeper than it really is. This is because after crimping, the case springs back open a bit, but the lead not so much. Yeah, I know I said that totally wrong.
 
Last edited:
You can't load generically "good ammo" using cast bullets.
This is so often so very true. If you're loading cast and getting poor results the bullets may not be properly sized for the bore. To remedy that you have to slug the bore and thing is, I've seen .354" - .357" in "quality" guns. A plated or jacketed bullet will likely do well, but cast is a whole different story with .001" over bore diameter being the usual starting diameter. And even then you have to be certain the case doesn't swage down the bullet upon seating. Same for crimping.
 
Why are you pulling the bullets? If they fit your magazine, chamber (proper "plunk") and shoot the way you want them too what else are you looking for?

The only crimp I apply is a taper that does little more than remove case flare. I do that in a separate operation and depending on bullet diameter shoot for .001"-.002" less than spec.

As already stated, the only case gauge that really matters is your gun's chamber.
I am pulling them to check for bullet deformation, which I am getting. I'm iquiring about the issue rather than just keep shooting them because I am trying to learn how to load correctly rather than just use them if they go boom.
 
GLOOB - Thanks for the feedback. I am/was trying to achieve good ammo for all my guns like you mention. A couple questions if you don't mind:

1. Why are cast bullets different than plated or FMJ in terms of size and sealing? I had this same crimping issue with Xtreme plated bullets too.

2. So you are saying people with say 6 different 9mm guns have potentially 6 different loads if using cast bullets? That seems like a ton of work.
 
Here's the good news. You do not need to slug your bore! You already have the biggest diameter bullet that will fit.

If those don't shoot, like I said. Try sorting your brass. Try using paper thin R-P cases, only, and see if those don't shoot more accurately. Do your testing at 75+ yards. At that distance, it is easy to see if your cast bullets are stabilizing.
 
My problem is that I'm new to shooting, not just reloading. I am not good enough of a shooter to be qualified to judge the accuracy of any given load. I'm sure most loads are more accurate than I am capable of right now. I've never even tried shooting a pistol at 75 yards. I'd probably be lucky to even hit a piece of paper at that distance.
 
My problem is that I'm new to shooting, not just reloading. I am not good enough of a shooter to be qualified to judge the accuracy of any given load. I'm sure most loads are more accurate than I am capable of right now. I've never even tried shooting a pistol at 75 yards. I'd probably be lucky to even hit a piece of paper at that distance.
You might want to give a little thought to mastering one new thing at a time. You can buy say 250/500 rounds of reasonably priced bulk 9mm ammunition and polish your shooting with a known load. Then move to hand loading.

You can, of course, do learning and loading simultaneously but if in your own words your not yet a "good shot" how do you know which area needs attention? And of course, if you buy in bulk to start with, you'll have brass to reload later.
 
You might want to give a little thought to mastering one new thing at a time. You can buy say 250/500 rounds of reasonably priced bulk 9mm ammunition and polish your shooting with a known load. Then move to hand loading.

You can, of course, do learning and loading simultaneously but if in your own words your not yet a "good shot" how do you know which area needs attention? And of course, if you buy in bulk to start with, you'll have brass to reload later.
I can see myself slowly getting better and when it tapers off I will try some manufactured ammo for comparison. I assume that should tell me whether it's me or the ammo.
 
I am pulling them to check for bullet deformation, which I am getting. I'm iquiring about the issue rather than just keep shooting them because I am trying to learn how to load correctly rather than just use them if they go boom.
Just my personal opinion, but I don't consider the "groove" you are seeing to be excessive at all. This is a relatively soft bullet (probably about 15 BHN) covered a polymer coating that will be even softer. Most sources recommend about 1-1/2 to 2 thousandths taper crimp. That is going to result in a groove of at least that depth (actually a little deeper due to spring back of the brass after crimping). I like the Acme bullets because they don't have a lube or crimp groove, but that does mean that crimping will leave the groove you see. Unless you penetrate the coating, you have not over crimped (as far as the bullet is concerned). I also use the FCD on coated bullets and have not identified any problems as a result.

Are you by any chance using mixed brass? Unless you are trimming your brass, there will be a difference in length, even with same head stamps. Mixed head stamp brass length can vary a surprising amount. That will affect the actual amount of crimp each cartridge gets, and if you are really trying to minimize the crimp, that could be the cause of the occasional cartridge that hangs up.
 
Just my personal opinion, but I don't consider the "groove" you are seeing to be excessive at all.
I had the same thought. What I've seen many times is a excessive roll type crimp that actually grooved and sometimes cut the plating or coating. These appear to be an evenly applied taper crimp that may well be fully acceptable accuracy wise.

Go shoot some report back. I'm interested in how you do. But if it were me, I'd start at three yards and work back to seven then ten. 75 yards will definitely demonstrate "long range" stability, but for a beginner that could well be a little confidence busting.
 
I appreciate everyone's feedback on this. I only care about the crimp marks on bullets in so far as it affects safety and accuracy. I have just been told on numerous occasions that mine had too much and have been trying to go about correcting it.

Yes, I am using mixed brass and I was aware of length issue and the effect it could have on crimp. I hadn't worried about it thus far because my problem has been consistent. That would be great if it's not an issue with soft bullets like the and makes a certain amount of sense when I consider the recommended dimension and that mine are pretty close to those.

I'll go shoot what I've got and see how they do.
 
I have 5 different 9 mm pistols,load with my own cast bullets and on a Dillon 650. This is how I set my crimp die and it's very simple and my reloads fit all my pistols even the one with a match chamber.
Take a resized empty case screw down your crimp die till it touchs then case lower the case and turn the die 1/16 -1/8 of a turn then lock it down you should get a decent crimp. I used to use a case gauge but drove myself nuts trying to get loaded rounds to fit,as many have said use your barrel as a gauge and you'll have better success finding the right crimp.
 
I have 5 different 9mm pistols.
I know which one has the tightest/shortest chamber (lucky both are in the same gun) so if my round if my round plunks there I know I am good to go.
I have shot a lot of MBC cast bullets and while the different pistols prefer slightly different loads/OAL with them to get the best accuracy I found what one likes really well the others are happy with.
I do find the same issue with plated or jacketed. Each on tends to have it's own favorite so I end up with loads that are not as good as they good be if I was just loading for one pistol. If I shot competition I would load for each gun I used, but since I don't right now I compromise.



Lately I have been shooting a lot of the RMR 9mm 124 gr hardcore flatnose.
They are my new favorite practice bullet.
 
Happy to see your having fun reloading but like many that are new to loading they make a few basic mistakes. 9mm should not be crimped ever, your picture shows a crimp. Back off your die and quit crimping. If you are not comfortable with not crimping or have bullets that are not staying in place Lee makes a factory crimp die that will not roll the brass and cut into the bullet. You could produce a dangerous condition by crimping 9mm, high pressure. The ammo you make should be better then factory. Do you understand chamber sizing brass?
 
I have many 9mm handguns, been loading this cal. for 100 years:)
Never have used a case gauge, your barrel is your friend.
I bell the case just enough to start the bullet without compromising the coating on the bullet.
After seating, I remove just the bell, nothing more.
Most of my shooting is with my cast bullets and powder coated, sized to .356 and .357, upon pulling bullets, none show markings from crimping, even the
.357 sized bullets. Using mixed range brass---all except Amerc brass.
That's my story.
Floydster a.k.a. Smokeyloads
 
I'll agree with that Bill. Taper crimp to take care of any flare but 9mm headspaces on the case mouth. The square edge of the case mouth should butt up against the ledge at the end of the chamber. A roll crimp allows the case to go a little too far, then there's no where for the case to expand to and can lead to excessive high pressures.

Look at a factory 9mm, there's always a 10 - 12 thou lip.
 
Many people here have said to put your case gauge away in a drawer and use your barrel to plunk test the rounds. Unless I missed it, you haven't said whether you've tried that yet. If not, please do so before you confuse yourself any more than you are. You might not have a problem at all.
If your loaded rounds fail the plunk test but the unloaded sized cases pass, then it seems your problem is with either the bullet or the crimp. I'm leaning toward the crimp. Taper crimp only enough to remove the flare.
 
Status
Not open for further replies.
Back
Top