Dillon Resize Die: Potential setback Issue

[Phlier]

Recently on another forum, a guy mentioned that he had seen setback issues in 9mm rounds loaded with a Dillon resize die and FMJ bullets. He mentioned the problem was specific to FC headstamp brass.

I have quite a bit of FC brass in my assorted 9mm collection. I don't sort 9mm by headstamp before loading, and unfortunately, had never checked FC specifically for setback. The few rounds that I test at the start of a reloading session and randomly during reloading have never caught this issue.

After being informed of this, I checked 10 FC rounds I had loaded up, and all of them had setback problems. I also checked the remaining headstamps, which were all fine.

I just recently switched from plated bullets (which he stated don't have this issue as it's an FMJ specific problem) to FMJ's, and was very much surprised by this.

This situation has given me pause. In spite of what I consider to be a very careful, methodical practice of reloading, a potentially serious problem slipped through the cracks. Not only is it embarrassing to admit, it's also dangerous.

So I just thought I'd let you guys know that if you're using a Dillon 9mm resize die, FMJ bullets, and have FC brass in your rotation, please be sure to check them for setback problems.

My specific setup that resulted in this issue:
Dillon Carbide 9mm Resize Die
FC Headstamp cases
115gr RMR FMJ (which I love, btw)

You guys that sort 9mm by headstamp... now I get it.

I do have an RCBS 9mm carbide resize die, and will check FC brass for this issue when time permits.

 

[Schwing]

How much setback are you talking about? I know it can be an issue but, my experience has been that it is rarely more than a few thousandths which makes virtually no difference. IMO, the only time this would be an issue would be if you are talking about excessive setback (like .020 or more... ), you are already seating your bullets shorter than spec or you are exceeding max loads.

 

[Phlier]

How much setback are you talking about? I know it can be an issue but, my experience has been that it is rarely more than a few thousandths which makes virtually no difference. IMO, the only time this would be an issue would be if you are talking about excessive setback (like .020 or more... ), you are already seating your bullets shorter than spec or you are exceeding max loads.

The issue wasn't found by examining cases retrieved from a magazine that had experienced actual setback (thankfully), so I can't give you that number.

I believe that most reloaders check for bullet setback by pressing a round against the bench. I usually have to push pretty darn hard to get a 9mm with proper case tension to setback into the case.

In the instance in question, I would *estimate* that 20 lbs of force resulted in the bullet moving rearward in the case continuously until the compressed powder stopped it. It was quite easy to push it back. Too easy. How much actual setback that would result in, I'm not brave enough to try.

 

[2bfree]

Not a problem with mine using PD 124 and FC brass. You might try turning your die down another 1/4, 1/2 turn.

 

[fguffey]

After being informed of this, I checked 10 FC rounds I had loaded up, and all of them had setback problems.

Set-back what!? What is being setback? Is this happening while the case is being sized or when the neck is expanded or when the bullet is being seated and then there is the crimp?

F. Guffey

 

[Phlier]

Set-back what!? What is being setback? Is this happening while the case is being sized or when the neck is expanded or when the bullet is being seated and then there is the crimp?

F. Guffey

Crimp has little to no effect on bullet to case tension in 9mm, as well as a lot of other semi-auto calibers. There's a great thread about it here on thehighroad, but I don't have a link to it handy.

Keep in mind, I'm not the only one that has experienced setback with this setup. It was brought to my attention by a guy on another forum.

But to expand on the process that resulted in this situation (in a 1050 press):

FC Brass
Dillon 9mm Carbide resize/decap die
Primer pocket swage (unnecessary, of course, since it's not a military case, but it's a station on the 1050)/ case mouth expansion
Primer seating
Dillon powder through funnel die (case mouth belled just enough to place a bullet on top)
Dillon bullet seating die (115gr RMR FMJ set to 1.125 OAL)
Dillon taper crimp die (.378 at the mouth).

Pressing this round against the bench to guestimate bullet to neck tension resulted in the bullet moving rearward in the case until compressed powder stopped it, at *approximately* 20 pounds of pressure. While that is most likely far from an accurate estimate, it was far too easy to set the bullet back.

I'm not sure what other information I can give to answer your questions.

Edit: Gents, please keep in mind that I'm not posting this for you guys to pull my reloading process apart, and ask questions I'm far from capable of answering. I'm merely posting it to state that in 9mm, with FC Brass, Dillon resize die, and FMJ projectiles you *might* have a setback issue (as reported by others and myself), and that you should check for it. That's all.

 

[mdi]

Mic your bullets and try and measure the ID of a sized case. Should be .003"-.004" interference fit. Try with the thinnest walled cases you can find. And how does it feel when the bullet is seated.

OOPS! forgot you're using a progressive...

 

[Phlier]

Mic your bullets and try and measure the ID of a sized case. Should be .003"-.004" interference fit. Try with the thinnest walled cases you can find. And how does it feel when the bullet is seated.

OOPS! forgot you're using a progressive...

Still a great idea. I'm going to do precisely that with FC brass sized from both a Dillon die and RCBS die.

 

[jmorris]

I press check all of my rounds right after they are case gauged and boxed, I can quickly row by row push on every base, if the bullet pushes further in the case, it will now be shorter than all the rest and easy to see.

Crimp has little to no effect on bullet to case tension in 9mm, as well as a lot of other semi-auto calibers.

You are right and wrong. If done properly it will have little effect. If you over taper crimp a case you will swage the bullet to a smaller diameter. Then you remove the round from the die and the brass case "springs back" but the lead bullet stays where it was crushed to and you loose neck tension.

Pull some of your loaded rounds and measure the OD of the bullet.

 

[jmorris]

But to expand on the process that resulted in this situation (in a 1050 press):

FC Brass
Dillon 9mm Carbide resize/decap die
Primer pocket swage (unnecessary, of course, since it's not a military case, but it's a station on the 1050)
Primer seating
Dillon powder through expander die (case mouth belled just enough to place a bullet on top)
Dillon bullet seating die (115gr RMR FMJ set to 1.125 OAL)
Dillon taper crimp die (.378 at the mouth).

The 1050 does not use a powder through expander die, only the SD, 550 and 650's use them. On the 1050 the expander is incorporated into the backup rod for the swage station, so it is sort of important.

 

[Phlier]

The 1050 does not use a powder through expander die, only the SD, 550 and 650's use them. On the 1050 the expander is incorporated into the backup rod for the swage station, so it is sort of important.

Yes, that is an important distinction. I need to look up the proper nomenclature for that die on a 1050.

I'm quite certain that one of the guys that reported this issue on another forum was using a 650, so it doesn't appear to be a problem related to the 1050 swage backup rod.

 

[Phlier]

I press check all of my rounds right after they are case gauged and boxed, I can quickly row by row push on every base, if the bullet pushes further in the case, it will now be shorter than all the rest and easy to see.

You are right and wrong. If done properly it will have little effect. If you over taper crimp a case you will swage the bullet to a smaller diameter. Then you remove the round from the die and the brass case "springs back" but the lead bullet stays where it was crushed to and you loose neck tension.

Pull some of your loaded rounds and measure the OD of the bullet.

My abbreviating the whole concept of how taper crimp effects bullet to neck tension was an (unsuccessful) effort to summarize a very lengthy and informative post here on this forum. Unfortunately, it is a subject that can't really be summarized; the entire post should be read top to bottom. I just wish I had a link to it.

I really like your process of checking your rounds.

 

[jmorris]

They simply call them all "powder funnels".

The 1050 funnel (left) only bells the case mouth and is not specific to the exact pistol round your loading. The ones for the SD, 550 and 650 (center) expand and bell the mouth and are specific to the round your loading. Rifle funnels (right) do not expand and are the same for all 4 machines.

http://i664.photobucket.com/albums/vv5/qvideo/IMG_20150414_231942_568_zpsrdhiqruf.jpg

Edit the photo posts gigantic but you can click the link to see the differences.

 

[Phlier]

Very nice picture. And yes, I am aware of how the 1050 handles case mouth expansion and belling. But I'm sure it'll be great information for those who aren't aware of the differences between how it's handled on the various Dillon presses. Having been used to loading on a relative's 550 and my LCT, I simply used the term I'm accustomed to using. But don't let an inappropriately used term lead you to believe that I don't understand my press. I do. Very well, in fact.

However, I can see how my above post could very well lead to that conclusion. I'll go edit/correct it now.

 

[Jim Watson]

When I occasionally load a supply of 115 gr JHP for defense gun practice - my carry ammo is a 115 gr factory JHP - I substitute or just pre-process brass in an EGW/Lee "U" die.

Likewise 185 or 200 gr JHP .45s.

I do not have trouble with setback, even in FC brass with Dillon die, with my IDPA 147 gr plated load.

 

[Schwing]

The issue wasn't found by examining cases retrieved from a magazine that had experienced actual setback (thankfully), so I can't give you that number.

I believe that most reloaders check for bullet setback by pressing a round against the bench. I usually have to push pretty darn hard to get a 9mm with proper case tension to setback into the case.

In the instance in question, I would *estimate* that 20 lbs of force resulted in the bullet moving rearward in the case continuously until the compressed powder stopped it. It was quite easy to push it back. Too easy. How much actual setback that would result in, I'm not brave enough to try.

That does sound like they are pretty loose if they push in that easily. My S.O.P. is to push them against the table or something like you do. If they move at all (I measure with calipers) then I load a couple in a magazine and cycle them through my gun (with the safety on etc).

If they don't move more than .010 or so I don't even worry about it. Even up to .020 I would not worry about a safety issue unless, as said earlier, you were already at max load or were at a very short OAL already. You may or may not lose accuracy but I do not believe it is much of a safety issue.

I don't mean to make light of bullet setback. I know it is a real thing and can and has caused problems, not just for re-loaders but for folks who don't rotate their ammo and empty and re-chamber rounds repeatedly. In those cases however, you are talking about rounds that have usually been re-chambered many times and have been pushed far more than .020.

Having said that, I have run across various head stamps of brass in various calibers that did not provide good consistent neck tension. Those cases get sorted out and left on the range floor after the first firing

 

[mdi]

I didn't mean to bad-mouth progressive press, it's just more difficult to feel bullet seating resistance with other things going on at the same time...

 

[Phlier]

When I occasionally load a supply of 115 gr JHP for defense gun practice - my carry ammo is a 115 gr factory JHP - I substitute or just pre-process brass in an EGW/Lee "U" die.

Likewise 185 or 200 gr JHP .45s.

I do not have trouble with setback, even in FC brass with Dillon die, with my IDPA 147 gr plated load.

As stated in the OP, this has been found to be an issue with FMJ bullets only, not plated.

Edit: Forgot to add that I've read great things about the Lee U-die. I've been intending to order one for quite sometime.

 

[jmorris]

Having been used to loading on a relative's 550 and my LCT, I simply used the term I'm accustomed to using.

I understand and am not a stickler as much as others, I knew what you were talking about.

Having loaded on the 550 and LCT too, did you have the same issues you are now having?

Is it repeatable with every FC 9mm case?

If so, can you test one out of station 7, after seating but before crimp and see if it also sets back?

 

[fguffey]

Keep in mind, I'm not the only one that has experienced setback with this setup. It was brought to my attention by a guy on another forum.

If my set up fails to produce enough bullet hold I increase the case's ability to hold the bullet. I measure bullet hold in pounds, I would use neck tension but I do not have a gage that measures tension. When it comes to cases there is no shortage of Federal/FC cases here. I do not have new FC cases but if there was a difference between different brands of cases and bullet hold I would have experienced the problem.

I did have a problem with reloads in two pistols, both pistols like new over the counter factory loaded ammo. It had nothing to do with loose bullet in the case, it had to do with the appearance of the case. The cases looked like they swallowed a bullet, my cases had bullets lines. I used a RCBS carbide sizing die to remove the slight bulge. Not to my amassment the bullets were not crushed and the bullets did not get loose and both pistols shot my reloads like I was shooting new ammo.

F. Guffey

 

[Phlier]

I understand and am not a stickler as much as others, I knew what you were talking about.

Having loaded on the 550 and LCT too, did you have the same issues you are now having?

Is it repeatable with every FC 9mm case?

If so, can you test one out of station 7, after seating but before crimp and see if it also sets back?

When I was loading on my Father's 550, I was loading his supply of brass, which was all surplus military; no FC headstamps, and using plated bullets.

But you are reading my mind... I'm going to pop the Dillon 9mm dies into the LCT (I haven't used the LCT for 9mm yet, as that's the 1050's job. Prior to the 1050, I loaded 9mm using RCBS dies on a Rockchucker) and see how they turn out. I won't be able to use the expander rod from the 1050, of course, so the expanding/belling will be done by an RCBS die, as I don't have a powder through expander die for the LCT in 9mm (yet. Ordering it today).

I currently have about 1k of loaded 9mm, all in mixed headstamps. I pulled out 10 FC cases, and all of them had the same setback problem.

Yes, I'll check right out of station 7, prior to crimp.

But one thing I'd ask you guys to keep in mind... I'm not the only one reporting this issue. The ONLY reason I found it was that it was reported on another forum by someone else.

Now I don't have the numbers and data to back this up, but my guess is that the Dillon resize die simply doesn't size FC brass down far enough for it to provide adequate neck tension on certain FMJ bullets.

If I was the only one experiencing this issue, I would be doing exactly what you guys are doing; pulling my reloading method apart. But I'm not the only one, gents. What are the odds that everyone experiencing this issue is doing exactly the same thing wrong that is necessary to produce this problem? Do we all have exactly the same taper crimp setting to cause a loss of bullet tension? Most likely not. Is it a problem with the 1050 swage backup rod? No, this issue has been reported on a 650. Is it the Dillon powder through expansion die? No, this problem has been reproduced on a 1050. Are we all seating to a too-long OAL? Unknown, but I'm seating to 1.125. What other commonality do we all share with this issue? We were all using Dillon 9mm resize die, FC brass, and FMJ bullets.

If you are using a Dillon resize die, FC Brass, and FMJ bullets, please check for setback issues. That's it.

Now I know checking for setback issues should be S.O.P. but for those of us that load mixed headstamps in batches, it's possible to slip through the cracks.

 

[Phlier]

My S.O.P. is to push them against the table or something like you do

I do this for the first several rounds loaded during a session, and then randomly as I load, as I also check for powder weight, OAL, and crimp. Unfortunately, when loading mixed headstamp brass, an FC headstamp was never checked.

 

[Jim Watson]

As stated in the OP, this has been found to be an issue with FMJ bullets only, not plated.

I would expect short light plated bullets to behave no better than FMJ if the sizing die was large and the brass thin or soft. I would not take the chance.

I have had other brass that would not give good bullet pull on short slick jacketed, plated, or even minimum diameter cast bullets. The last occurrence was with some WW 9mm, and before that RP .45.

The ammo company doesn't care, they had rather you buy new than reload the old anyhow.

You have some options here. Sort the brass, change the bullet, or change the dies. I found "U" dies to be what I needed. There is also the possibility that the expander (Dillon "Powder Funnel") is too large.

 

[jmorris]

Now I don't have the numbers and data to back this up, but my guess is that the Dillon resize die simply doesn't size FC brass down far enough for it to provide adequate neck tension on certain FMJ bullets.

Now you have something you can measure right now with what you have already setup.

Take a case and measure it right out of station #2 after sizing but before being expanded in number 3.

Write that number down, now take the case and run it in #3.

If it changed your die is sizing the case down more than the expander will allow.

Any smaller diameter die won't do you any good because the expander will just stretch it back out.

My 9mm 650 sizes the case .375 out of the size die then bells it out to .380, below the bell it's .375.

My 9mm 1050 sizes down to .375 and there is no change after the expander.

Looks like my expanders don't do anything unless there is an ID imperfection that the OD size could not take care of.

Being that they are all OD measurements, they won't directly indicate an issue but could be used for reference.

If you also happen to have a tube micrometer to measure case thickness, that would be helpful too.

 

[Phlier]

Now you have something you can measure right now with what you have already setup.

Take a case and measure it right out of station #2 after sizing but before being expanded in number 3.

Write that number down, now take the case and run it in #3.

If it changed your die is sizing the case down more than the expander will allow.

Any smaller diameter die won't do you any good because the expander will just stretch it back out.

The 1050 is currently setup for .223. I've been putting off switching it back over to 9mm, but now you have seriously piqued my curiosity.