What am I doing wrong? 9mm

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Thompsoncustom

Thompsoncustom

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I've been having some undersizing problems lately after I turned down my lee expander plug which is no big deal as that gave me a good reason to buy an M die. So M die came in today and I loaded 40 rounds and decided I better pull one just to make sure it's not undersized. Before I loaded the bullet is measured .3565 and after I pulled it .351

What the heck is going on. Seems like no matter what I do these days all my bullets are undersized by the case. This is how my reloading has been going. On the Hornady LNL I resize and deprime and reprime the case, after that is all done I set up the Lyman M die is station one, LNL powder drop in station two, Three empty, 4 lee seating die, and 5 empty.

After I found out they were being undersized I back off all crimp completely and tired again but that made to difference.

The bullets are lee 125gr WW that are air dropped. Could the lead be to soft? I would think you could run pure lead so I don't think that's the issues but at this point im lost.
 
measure the M die to make sure it is the proper size, they usually aren't for cast. If you are loading 0.356, then you need a 0.354 M die. ACWW is fine for alloy, you could water drop to get harder but using the cast for an expander is not the way to go.
 
I agree with popper. Have a custom expander plug made for the m die. For a .356 bullet you want .354 minimum, but I'd prefer a plug around .355 because the brass always "springs" back some after expanding. Some brass is far worse than others in this regard. I highly recommend separating by head stamp for 9mm especially. You may be tempted to try the 38/357 plug but I believe it's .356 and is too long for 9mm - you'll buckle the case before the plugs second step comes into play.
 
You might try expanding deeper and/or loading to a longer OAL. Also try sorting by headstamp. A lot of 9mm cases start getting thicker really high up. You might have better luck with Speer, R-P, and Blazer cases.

If you're using a Lee FCD, stop.

Additionally, since you already use Lee dies, you can always try a 38S&W expander plug in your 9mm expanding die. This is already made the perfect diameter for 9mm cast bullets. It only costs a few bucks, and Lee Precision will probably have it to your door in 2-3 days. It has worked for lots of smart folks who were generous enough to share their experience on forums. And it works for me. The 38SW plug expands much deeper, as well as bigger. But I still load a little long, leaving nearly 2 grooves exposed on my Lee 124/5 gr tumble lube grooved bullets. This ensures the base of the bullet stays in the expanded part of the case.

MBC bullets worked ok in my pre-38SW expander days. Fouling was moderate, and accuracy was at least usable out to 20-30 yards before flying off the charts. I presume they worked as well as they did because they're much harder than my own bullets. My own bullets were horrible. Accuracy was abysmal, and even Chore Boys were stumped; I scraped the lead out of the barrel with a brass tube! But now, these same bullets put all my previous 9mm cast efforts to shame. They shoot accurately out to at least 100 yards (farthest I've tested) with virtually no leading.

Sometimes, it's not the bullet. It's the expander!
 
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Taper crimp die screwed in too far.
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Crimp made to difference.

You may be tempted to try the 38/357 plug but I believe it's .356 and is too long for 9mm - you'll buckle the case before the plugs second step comes into play.
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Couldn't you just cut off the bottom part of the plug and reprofile it?

you can always try a 38S&W expander plug in your 9mm expanding die
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I've heard great thing about the 38sw expander for 9mm. I think i'm gonna call Lyman and see what the diameter is on there 9mm,.357, and 38sw plugs and probably order a couple and see what works.
 
If you have a lee 38/357 expander plug you need to make a spacer so it goes in deeper when placed into the 9mm expansion die. I kludged a spacer with a .45 ACP case and it worked, but after a few rounds, the case collapsed, but I didn't really need the deep expansion anyway. You could fill the case with lead or hot glue to make the case more solid or cut a small section of delrin rod, a piece of brass or whatever to make a spacer.

Most importantly, you aren't swaging the bullets down with a Lee FCD right?
 
Most importantly, you aren't swaging the bullets down with a Lee FCD right?
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:cuss:Never~!

My guess is that I'm not expanding enough for the bullets and I was water dropping them and switched to air dropping not to long ago. Now that the bullet is softer it is probably just being undersized pass the point of the bore diameter.

Tho I would like to run super soft bullets and not have them undersize any.
 
If they are soft enough for the brass case to swage them down?

They are soft enough to get bumped back up to fit the bore when kicked in the butt real hard by the powder charge.

Have you tried shooting them to see?

rc
 
Since I got the M die no I haven't but I'll shot the 40ish I loaded and see how they turn out. Is accuracy any good when bumping bullets up?

The lee die that I turned down to .350 I shot 150. The 102grs must have bumped up as they didn't lead but they were tumbling. The 168gr SWC seem to work normal no lead or tumbling. The 124 leaded like a sewer pipe.
 
The bullets are lee 125gr WW that are air dropped. Could the lead be to soft?
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Air dropped WW metal is generally fine in the 9mm, but not if you're loading them the same day you're casting them. They need several days to reach their maximum hardness before loading them. If you have access to some scattergun shot you might try adding an ounce per lb of WW to the pot to get some arsenic in the mix...it generally is already in WW's and then drop quench them. If you're indeed using an (M) die you shouldn't be having this problem anyway. Even a LFD wont squeeze a bullet down that much...mine in 9mm doesn't even reduce .357 bullets. I'd blame that darn seating die if I was having this problem.
 
Measure the case ID after expanding. It should be 0.353-0.354" for a .355" bullet. For lead bullets, 0.357" is usually better than a 0.356" and you will want the case ID to be 0.355-0.356".
New cases have no spring back and will have an ID almost the same as the expander OD. Old cases are work hardened and can spring back several thousandths. This is why calipers are often found on reloading benches -- one should measure and find out what is what.
The good thing is that even if Lyman doesn't have the exact expander OD you want, they can make one for you.
However, your measured bullet OD is so small, there is something wrong (and it ain't the alloy or the "hardening" time). Either your M-die is too small, you haven't adjusted it down enough, your crimp is excessive or something else is really wrong. Not using a Lee FCD die you?
In casting for 40 years, I have never worried about casting, lubing, and loading in single day and don't understand the "need" for water quench or aging for a low velocity round like the 9x19. Maybe somewhere north of 1600 fps, but for 9x19?
In fact, for a little over 35 years, I have not sized a single cast bullet. Seemed to me that sizing a bullet defeated the whole idea of water quenching and the as-cast bullets were always as accurate or more accurate than my sized bullets. Since my goal is accuracy, I stopped doing things that did not have a positive effect on accuracy.
 
UPDATE: I just realized I used one pair of calipers to measure the bullet and a different pair to measure the M die stem. With my new pair it measures .354 so way better but still undersizing. Old calipers are 20ish years old might be time to retire them. That and I need to invest in a mircometer.

Maybe somewhere north of 1600 fps, but for 9x19?
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Well the highest I've chronoed a group is 1700fps but I'm working on going faster :) but that's with a zinc/alum alloy whole different topic.

I cast these bullets two weeks ago I believe, tho I coated them with Hitek supercoat a day or two after casting so that might slow down the age hardening. But with the coating you can push a softer bullet a lot faster before u have leading problems. Very neat product.

The top of a loaded case measure .380 for the most part some down to 378 and up to 381.
 
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I have never worried about casting, lubing, and loading in single day and don't understand the "need" for water quench or aging for a low velocity round like the 9x19. Maybe somewhere north of 1600 fps, but for 9x19?
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It isn't the velocity that causes problems in the little nine with cast bullets, but rather the pressure. Also allowing the metal to harden helps when shoving oversize lead bullets into tapered cases. I assume you don't load cast bullets in the 9mm?
 
rcmodel said:
If they are soft enough for the brass case to swage them down?

They are soft enough to get bumped back up to fit the bore when kicked in the butt real hard by the powder charge.

Have you tried shooting them to see?

rc
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I'm also interested in the answer to this question.
 
I assume you don't load cast bullets in the 9mm?
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That's all I shoot.

I'll try to get out this weekend and shoot the 40 I got. Also ordered two plugs for the M die for a .357/38SW I was going to order a custom size but they said they don't do any custom orders.
 
>It isn't the velocity that causes problems in the little nine with cast bullets, but rather the pressure. Also allowing the metal to harden helps when shoving oversize lead bullets into tapered cases. I assume you don't load cast bullets in the 9mm?

All I have loaded for almost 40 years in 9x19 are my cast lead bullets. Since about 1974, all have been as-cast. The 9x19 is NOT a high pressure cartridge and I've have NEVER seen a need for an alloy harder than 13 BHN. My cast bullets tend to cast at 0.3565-0.3575" and work GREAT. A light tumble lube and I have no leading issues.
What helps in shoving oversized lead bullets into a tapered case (remember the case ID increases as you go down the case) is to get the right size expander and USE it. Most new reloaders seem to think that all an expander does is flare/bell the case mouth.
Sorry, but do you have almost 40 years of loading your cast lead bullets in 9x19s ranging from 1930-era P-08s, BHPs, Walther P-38s, GHP, S&W, 1911, CZ75, and others?
 
Well shot 15 of them today and they leaded the barrel bad enough that I decided to stop. So there soft but there not bumping up and there warm. about 1150fps if I had to guess using quickload, ejecting about 10ft.

I'm just gonna pull the couple that are left and hope the lyman plug for .357 works.
 
A year or so ago I was getting low readings and discovered my ancient calipers were reading under by a few thou. New set solved the problem. Getting used to digital ain't easy though.
 
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