9mm dies and bullet setback

[chb119]

Yesterday I spent numerous hours trying to set up my LnL AP with new Hornady 3 die set 9mm dies. The problem I am having is that when the round is finished, and I push the cartridge between the bench and thumb I am getting significant push back. The bullet is moving back quite easily on some.

I adjusted all the dies numerous times but cannot seem to figure this out. The resizing die appears to resizing it down. The expander die even with the lightest flare still does not do the trick, is it the seating/crimp die or an I completely off base?

Any suggestions would be great.

[lcs]

Yesterday I spent numerous hours trying to set up my LnL AP with new Hornady 3 die set 9mm dies. The problem I am having is that when the round is finished, and I push the cartridge between the bench and thumb I am getting significant push back. The bullet is moving back quite easily on some.

I adjusted all the dies numerous times but cannot seem to figure this out. The resizing die appears to resizing it down. The expander die even with the lightest flare still does not do the trick, is it the seating/crimp die or an I completely off base?

Any suggestions would be great.

If the case is sized correctly, it should be pretty hard to push the bullet in (past the bell portion). When the case comes to the bullet seating position, take out the case and seat the bullet manually. If you can push the bullet in real easy, then your cases are sized incorrectly. You may be "belling' the case more than you think and the whole case is expanding.

[DWFAN]

Yesterday I spent numerous hours trying to set up my LnL AP with new Hornady 3 die set 9mm dies. The problem I am having is that when the round is finished, and I push the cartridge between the bench and thumb I am getting significant push back. The bullet is moving back quite easily on some.

I adjusted all the dies numerous times but cannot seem to figure this out. The resizing die appears to resizing it down. The expander die even with the lightest flare still does not do the trick, is it the seating/crimp die or an I completely off base?

Any suggestions would be great.

My 9mm Hornady dies do the same. I tried everything. Got tired of messing with it and bought a Lee U-Die and run it instead of the Hornady sizer. No more problems.

[hueycrew]

Had to do the same thing. Bought the U-die and the problem went away. Had the most problem with Federal brass. Winchester was the only brass that would size correctly with the old die.

Problem solved in my case.

[DWFAN]

Had to do the same thing. Bought the U-die and the problem went away. Had the most problem with Federal brass. Winchester was the only brass that would size correctly with the old die.

Problem solved in my case.

Federal was my issue also. R-P was the only one that wouldnt. Win was about 95% acceptable.

[Sarge]

Get the Udie.

[dsmw5142]

Call Hornady first. They are a reputable company and will take care of you. My Hornady dies work fine with 9mm and .45, all brass everyday.

That said, the U-die is great too and I have one for .40

[Seeker]

My 9mm Hornady dies did the same thing. After messing with it and messing with it, I bought a Lee U-Die and run it instead of the Hornady sizer. I also had the same problem with .45 Hornady dies with RP brass and plated bullets. So now I use a Redding .45 sizer without problems.

[Babaganoosh]

Before you go out and just buy a new die make sure your sizing dies is set correctly. Make sure it is all the way down to the plate when the ram goes up. Then make sure you aren't belling the case too much. It should only be enough to hold the bullet. I've only made about 10k in 9mm but I haven't had that problem.

It's also possible that you have the seating/crimping die set incorrectly. You could be pushing the round too far into the die and pushing it too far into the case. I would check the other 2 theories first though.

For what it's worth most if not all of us seat and crimp in 2 different stations. It's a lot more consistent.

If you can take a pic of how much you are belling the case it would help a bit.

[Desmo412]

I have loaded upwards of 20k rounds on my LNL with a hornady sizing die and have never had any setback problems. While I am sure the U-Die is a great product, I would double check the settings at all stations before I started changing dies. I will second the above comment, always seat and crimp in 2 different stations. If the sizing die is actually out of spec, call Hornady. I'm sure they would send you a replacement.

[BoyGlock]

maybe the brass has different wall thicknesses? I encounter a lot of this problem and I cant find fault on my dies, adjustments and heads. I found some case has thinner walls than others. W/ thinner case walls, I could push the head into the case even before the belling sta. After belling, the head almost loosely fits into the case mouth. After crimping, I could turn the head loosely against the case mouth.

Edited March 6, 2012 by BoyGlock

[acekc]

Yesterday I spent numerous hours trying to set up my LnL AP with new Hornady 3 die set 9mm dies. The problem I am having is that when the round is finished, and I push the cartridge between the bench and thumb I am getting significant push back. The bullet is moving back quite easily on some.

I adjusted all the dies numerous times but cannot seem to figure this out. The resizing die appears to resizing it down. The expander die even with the lightest flare still does not do the trick, is it the seating/crimp die or an I completely off base?

Any suggestions would be great.

As a test, size a piece of brass in the sizing die and then try to push a bullet into it by hand. It shouldn't really go at all, if it does there's something wrong with either the sizer die or how it's set up.

Next move the brass to the station with the seater die. I've found that while testing you can hold the sides of the bullet even with the top of the brass until the seater die insert goes down over it and captures it, then let go of the bullet and run the ram the rest of the way up and seat the bullet. Go slowly and be very careful not to smash your fingers.

If you do this and the bullet is seated securely when you're done, it's likely that the expander die is set too low and is applying too much flare to the case. You only want it to flare the top edge of the case out far enough that the bullet can be pushed into place and stay there until it's seated. Too much flare can cause the loose hold on the bullet you're describing. In my opinion the answer to "How much a case should be flared by the expander die?" is "as little as possible."

Finally since you're using a Hornady die set, is the part number of the die set 546516 or 546515? Until recently Hornady's seater dies applied a roll crimp even on cartridges like 9mm that should have a taper crimp. They claimed that the die could be set to do a proper taper crimp but I could never make it work. If you have the 546515 set then you have the older roll crimp set and should adjust the die so it doesn't crimp at all, then use a Lee taper crimp die in station 5 after seating. If you have the 546516 set it supposedly comes with a seater die that taper crimps but I have no experience on how well it works.

[Sarge]

maybe the brass has different wall thicknesses? I encounter a lot of this problem and I cant find fault on my dies, adjustments and heads. I found some case has thinner walls than others. W/ thinner case walls, I could push the head into the case even before the belling sta. After belling, the head almost loosely fits into the case mouth. After crimping, I could turn the head loosely against the case mouth.

Bingo! It is well established that case walls vary enough to effect retention. For me FC and any CCI family are the worst. My Dillon size die would not size them down enough to prevent setback. I got a Udie and problem solved. it's only .001 smaller but it works.

[kend]

The sizing die is supposed to squeeze the brass down smaller than it should be and the powder funnel sets the inside diameter to get the proper case tension and pull on the bullet. The crimp only helps hold the bullet in place, the inside diameter set by the powder funnel should perform the majority of that function and would nullify any variances in wall thickness.

If you can push a bullet into the case after running it through the sizing die then it's not reducing the case diameter enough to allow the powder funnel to do it's job of resizing the inside of the case and you need another sizing die. Resize different brands of brass and take one that you cannot push a bullet into, run it through the powder funnel/flaring die and see if you can push a bullet into it. If you can then there is a problem with the powder funnel.

[eisenhow]

I've loaded thousands of precision black bullets and berrys plated bullets. I've never had any issues with setback until I recently tried Montana Gold CMJ's. It seems to be the worst with FC cases. I picked up a U-die but I feel like Goldilocks: The regular die is too big, the u-die is too small. I'm still fighting with it but I've got ~700 rounds loaded in FC cases that will setback .

[DWFAN]

Montana Gold's and some other jacketed bullets only measure .354 which could contribute to the issue. I have no issues with moly or lead bullets.

My Hornady press doesnt use a powder funnel. I get set back with or without flaring the case. The dies were set exactly to Hornady's instructions.

I'm perfectly content using my U-die.

[BoyGlock]

The sizing die is supposed to squeeze the brass down smaller than it should be and the powder funnel sets the inside diameter to get the proper case tension and pull on the bullet. The crimp only helps hold the bullet in place, the inside diameter set by the powder funnel should perform the majority of that function and would nullify any variances in wall thickness.

If you can push a bullet into the case after running it through the sizing die then it's not reducing the case diameter enough to allow the powder funnel to do it's job of resizing the inside of the case and you need another sizing die. Resize different brands of brass and take one that you cannot push a bullet into, run it through the powder funnel/flaring die and see if you can push a bullet into it. If you can then there is a problem with the powder funnel.

I used to think this way but after a lot of tests and analyses, its the wall thickness of the shell that really was the culprit. The powder funnel that bells the case mouth only expands the inside dia of the case only as far as it goes. beyond that its the wall thickness and the resizing die that controls the inside dia. After 2 dillon resizer dies, the problem remained. Between the resizer and the shell wall, I have more faith in the resizer dimensions than w/ the case wall thikness in different brands.

What I did was change bullet dia I use, from .355(9mm) to .356(.38 super)in my 9mm ammo. Problem solved.

[noylj]

If the bullet pushes into the case, then:

1) bullet is too small (VERY unlikely)

2) case walls are too thin (Most likely. RP cases are like this sometimes)

3) expander is too large (not likely)

4) bullet is being swaged down and case is springing back out (can happen if taper crimp is too much and cases are old and work hardened--they get springy, but the bullet is dead soft)

5) case crack at case mouth (not likely if you are getting this more than 1 in 200 or so)

The solution to the problem is to measure what is going on.

Take a case and measure OD, ID, and case walls. Measure your bullets. Some bullets are NOT 0.355" and may be 0.354".

Re-size the case and measure OD and ID. Is ID 0.354 or less? Good. Sizer is doing its job. Not the sizers fault. If case ID is too large, then your sizer is too large or the case walls are too small. Take bullet OD plus two case wall thicknesses. Should be 0.380. If less, case walls are too thin.

Expand case. Case ID should be expanded to more than 0.354" for jacketed or 0.355" for 0.356" lead bullets. If the expanded case ID is bullet diameter or greater, the expander is too large. If the case ID is more than 0.002" smaller than bullet OD, expander is too small--this certainly shouldn't be part of your problem.

When you go to seat the bullet, push it down with your finger. If it goes into the case too easily, pull that case.

If everything is good until the crimp step, then you may be over crimping to the point that the bullet is swaged down and the case is springing back. Compare measurements from each stage and see where problem is.

If a die problem, call Hornady and they will fix the problem. They, and every other reloading company want to know about any problems and they want to fix any problems, so contact them).

If it is your cases, either scrap them or try a small base sizing die (have never needed one myself).

Thin wall cases can be great for shooting 0.358" as-cast lead bullets, but aren't too good for 0.355" bullets, particularly thin-plated bullets.

[chb119]

I swithced out to a set of Redding dies the same ones I use for .40 and all the issues went away. Thanks for all the imput.

[noexcuses]

I had the same problem in 40 S&W and ende having to goto the EGW sizing die also and that took care of bullet setback issues, just my .02

[noylj]

I guess we'll never know the cause, just one cure...

Be sure to always check for bullet set-back, particularly in 9x19. 9x19 is the only round I have reloaded, over a 45+ year time span, where there are cases with walls so thin that resizing would not size those few cases enough to firmly grip the bullet--and this is with RCBS, Hornady, Lee, Pacific, and Redding dies. For me, it is a case issue and not a die issue.

[98sr20ve]

You don't need a U-Die, you just need a die that is properly made. My Lee dies work fine. Tighter then the masses but not too tight like the U-die. It's only .001" difference, but why go overboard if you don't need to.

[Sarge]

You don't need a U-Die, you just need a die that is properly made.

I guess that includes Dillon dies. With MG 124's and FC cases I could push the bullet in deeper with just thumb pressure against the bench.

Udie fixed the issue which is even more comforting since switching to 9MAJOR.