Importance of the right expander?

[gloob]

I learned something interesting, today. Long story to follow. Short of it: even if you think your bullets are not being case-swaged, an expander might make a difference?

The beginning:
My first attempt at shooting cast bullets in 9mm went rather poorly. MBC Small Ball, 18 BHN, .356", 125 grain bullets over 5.0 grains Unique in a Glock 19. I used both a stock barrel and a LWD. Minimal crimp, not even removing quite all of the flare. No FCD. OAL was about as long as I could fit mag/chamber, as I recall.

Fouling was moderate in the LWD barrel, showing up in certain patches of the bore, not super concentrated in any one area. Fouling was moderate to heavy in the stock Glock barrel, full bore, after just one shot. Accuracy was pretty bad in both barrels. Usable within 20-25 yards, anyhow. But I couldn't keep them in a 30 foot circle at 100 yards. The LWD barrel was probably more accurate, but that barrel is for my subcompact, which I never did shoot that well, so it was hard to quantify.

I shot up all 1000 I had ordered, anyhow. I learned to put a couple plated pills in each mag to keep the fouling from building up, and I cleaned the bore after each outing. I actually preferentially shot them out of the stock Glock barrel, because it was easier to clean. Then I went back to plated bullets.

At some point, I tried MBC bullets in my Glock 21, and they shot super clean and super accurate. No fouling.

So then I tried casting my own 9mm bullets. Straight WW for alloy, Lee tumble lube 125 gr mold. I shot them unsized, at .357ish, tumble lubed with Alox. First attempt, fouling was ridiculous. After one shot, there was so much lead in the bore, I stopped. I had to use a sharpened brass tube to scrape the lead out in big strips and chunks.

So about this time, I learned about case-swaging. I read some info on the Cast Boolits sticky. I pulled some of my bullets and measured the base as small as .353". I ordered a Lee 38SW expander for my Lee dies, and I tried again. I have been shooting those bullets ever after, and I have not scrubbed fouling from my G19 bores ever again. Not a hint of fouling, over 1k bullets later. I have not loaded nor shot a plated bullet, now, in about two years.

Fast forward a couple years. I decided to give those same MBC bullets a second try. I never measured pulled bullets back then, but I suspected the expander might make a difference. FTR, I'm now using an NOE .356/.360 expander. I didn't have any of those bullets left, so I ordered another 500 of the same Small Ball pills. When I got them, I put calipers on them, and I was disappointed to find they measured only .355 1/2" with my calipers. I hear of folks getting great results in their Glocks, using .357" boolits. And my first success was with the same. There is no way these tiny pills would shoot in a Glock, right?

Well, I shot a couple hundred of them over the weekend. Out of 3 Glocks. Two with stock barrels, and one with a LWD barrel. Everything looked fine in the field. Accuracy was good, and I didn't see any fouling. And when I got the guns home for a good cleaning, I got the final results. There was no lead fouling in any of the bores. The brass is the same mixed brass I was using back then. OAL is the same. The only thing that changed was the load. I have since backed off my load by 2 tenths of a grain for reasons unrelated to fouling.

Anyway, I thought that was very interesting. Regular .356" cast (maybe even on the smaller side of .356") bullets are shooting great out of multiple Glock 9mm's. And all it took was the proper expander plug. I have read multiple firsthand experiences that seem to show that case-swaging doesn't happen with commercial 18 BHN .356 bullets in 9mm. And at this point, I don't know if it ever did happen. But I am pretty sure the expander made all the difference.

I have also had a similar experience with 40SW, in both stock Glocks and another 40SW with a button cut bore. But in this case, I had to make a custom expander. I couldn't find one off-the-shelf, anywhere.

edit to add
Before making the custom 40cal expander, and using the regular Lee expander: First attempt was with commercial bullets. Had pretty bad fouling out of a Glock bore. I ended up shooting them all out of an FNX, and needing to scrub the bore, regularly. Home cast bullets were worse (presumably due to the softer alloy). When I finally made a custom expander, I tried MBC, sized to 401 (calipers show 401 - 401 1/2). I made the expander to the exact same diameter of the bullets. There was just a tiny hint of fouling in one of my Glocks with a tight chamber at the mouth. The fouling was just past the leade, and it easily came out with a regular bore brush; I have not kept Chore Boys around in a good long while. After sorting out my thick cases, I tried again, and got no fouling out of that gun, nor my two other 40 caliber firearms.

FTR, at one point I made a few rounds of cast 10mm using the regular Lee expander, and I couldn't measure the base of a pulled bullet. I had used new Starline brass, and the bullets would not pull. I couldn't even get them out by screwing a wood screw into the nose and pulling them with my press. After just about breaking my press and bench, the screw eventually tore out of the bullet. I ended up having to run them through the FCD to pull the rounds. Who knew a 180 grain cast bullet would be able to stick that tight in a case, where whacking it dozens of times in a kinetic puller on solid concrete can't even budge it?

I think at some point, I may have to dig up my old Lee 9mm expander and load up some of the Small Ball, so I can pull the bullets and measure the bases. I am curious if there is any perceivable/measurable swagging going on, of if there might be an even more insidious issue. Lead galling on the inside of the case due to too much tension?? With all the folks who swear that powder coating is the ONLY way for them to shoot cast 9mm, and insist that their bullets are not being case-swaged, I almost expect nothing there for me to measure/detect.

[Litl Red 3991]

You're discovering a couple of things.

The big one is that case resizing of your lead bullets happens. And not so obvious is that sometimes things happen and sometimes they don't.

Bottom line on both those discoveries is that what we do isn't sound byte simple. There usually are more reasons for why things happen than just one. In fact, you've mentioned two reasons for your "case swaging causes leading" situation. Sometimes the too-small cases don't cause leading because the lead is too hard to yield to the squeezing. Yup, not just one thing is usually working to cause leading.

Lead hardness responds to pressure levels. That's two right there instead of one. Lead with antimony in it often leads at lower pressures than simpler alloys of the same BHN is another factor.

Lot's of things are usually behind most of what happens that we're trying to figure out. Seldom are any of those things one dimensional. Yet humans seem to demand that our solutions all be sound byte simple.

[Litl Red 3991]

................
Anyway, I thought that was very interesting. Regular .356" cast (maybe even on the smaller side of .356") bullets are shooting great out of multiple Glock 9mm's. And all it took was the proper expander plug. I have read multiple firsthand experiences that seem to show that case-swaging doesn't happen with commercial 18 BHN .356 bullets in 9mm. And at this point, I don't know if it ever did happen. But I am pretty sure the expander made all the difference.

I have also had a similar experience with 40SW, in both stock Glocks and another 40SW with a button cut bore. But in this case, I had to make a custom expander. I couldn't find one off-the-shelf, anywhere.

Had a similar situation just the last couple of weeks with a couple of 32Mags. ....and a .357Mag I was trying to work up target loads in 357 cases. And did the same thing you did, made some expanders that suited the situation a lot better.

However, just as you noticed, just any BHN didn't work every case. And it also appeared some older alloy I was trying to use up that wasn't just tin and lead didn't work either. One trial so far shows that the slugs that didn't work right in spite of the new expander did actually work when kicked along by higher pressure.

I also started using some new brass during my testing. It showed a couple of things (probably). The old was splitting a lot with the new expander. Measuring the OD after that old brass was run through the resizer suggested the reason. Getting a new "cowboy" die that was from a set of dies made for lead bullets seemed to back up the suggestion, that the brass was being worked way too much and was already work hardened too much as well. Matching the sizer to the expander seemed to solve the splitting. I'm guessing the new, more flexible brass did too. And it seems that having a more appropriately sized sizing die makes as much sense as the right size expander.

I should mention that one of my "bigger" expanders wasn't homemade. It was actually included in a die set that was bought long ago and came with two expanders, one for jacketed and one for lead. Funny how the die sets we buy today don't come with but one expander. You think shooters today only need one size?

Wonder why the industry mostly thinks otherwise....

[gloob]

Re expanders for jacketed vs lead: Yeah, really. I measured my LEE 38SW expander at .356. I looked up the specs for 38SW, and it is supposed to shoot a .362" lead bullet. I can't imagine it works very well for the caliber it is actually made for.


However, just as you noticed, just any BHN didn't work every case.

Sometimes the too-small cases don't cause leading because the lead is too hard to yield to the squeezing.
I forgive anyone for not reading my entire post. It's a doozy. But in my case, the BHN's I used didn't seem to matter. Both the soft and harder bullets shot fine, as long as the cases were expanded, properly. It's just that the harder bullets weren't as bad when the cases were not expanded, properly. Even the hard and smaller commercial bullets improved with the bigger expander, from very mediocre to perfectly clean.

My idea is that maybe there's some issue with under-expanded cases that can't even be measured!? A very experienced reloader recently claimed that case-swaging isn't possible. Another guy stated he has reloaded cast bullet for over 30 years for some 20 different 9mm's, and he has never gotten 9mm cast to shoot without fouling; and he insists that his bullets are not being case-swaged, and that powder coating is the only answer for the problem. I have also read that only very soft bullets or those with "fragile" tumble lube grooves will case-swage enough to worry about. But the expander made a marked difference, even using hard cast commercial bullets with regular lube grooves. So I wonder if a larger expander could fix some problem, even though you are not seeing any case-swaging.

For some reason, my 45ACP ammo/guns were the only cast load that worked with a regular expander. I think it's because of the larger diameter and the thinner brass, mebbe. Heck, even my 357 ammo fouls a bit. I think an oversize 38 expander is on my to-do list.

[44man]

I suppose I have said 1000X that most problems are from brass, it is what I have found forever.
Closed breech guns do not need the same as revolvers where I want as much tension as I can get and do not expand deep so the hard boolit does the brass expanding.
Boolit length can bite you when the base reaches thicker brass and gets sized. I don't shoot nines but it sounds like the right expander is the solution.
I found smaller cases do not open much when a boolit is tight. Might be why accuracy is easier with large bores.
I will keep this in mind if I ever load for a nine, expand right and just past where the base of a boolit is.
Good catch and good info!

[DougGuy]

You also got to know that seating deeper in the case to get a boolit to feed and plunk will often times push it into the thicker part of the brass where it is inevitable that it will be swaged.

In this instance it is very helpful to know when to throat the barrel and be rid of the problems that come from seating deeper in the case as a workaround for not being able to seat to the COA that one would like to.

[44man]

So true, I never go with COA stuff at all, it is what fits. See how many look at COA from manuals! Last thing to fool with by measuring, your gun is the bottom line. It can be fixed.
DougGuy, only only thing I would never have done is a tailor throat in a revolver. Too much boolit velocity to engage rifling without skid. Forcing cone work only.
What is your opinion on this?

[rsrocket1]

Interestingly, I added this post to the 9mm sticky yesterday:
http://castboolits.gunloads.com/showthread.php?121737-Setting-up-for-boolits-in-a-new-9mm&p=3212795&viewfull=1#post3212795

It is a comparison of the too-short Lee 9mm expansion plug next to the 38 S&W plug and the 38/357 plug which also works for 9mm but needs to be longer to reach the 9mm case. The 38 S&W plug is the perfect fit for cast 9mm bullets.

[gloob]

Dougguy, good info. In my case, my 9mm Glock barrels all accept significantly longer than typical OAL, even the LWD. The magazine is the limiting factor for my 9mm loads, as I do not shoot any other 9mm firearms.


I found smaller cases do not open much when a boolit is tight. Might be why accuracy is easier with large bores.
44man, I suspect this might have some scientific basis. If you open up the case of a .452 bullet to .450, for example, it might not affect the bullet as much as when you open up a theoretical .003 bullet to .001 diameter, for instance. :) The circumference of the smaller case would have to increase by 3 fold to accommodate the bullet.

My experience and logic puts me at an expander of exactly equal to the diameter of the bullet (or only slightly smaller), and which expands at least as deep as where the bullet seats. For my .356 bullets, I use a .356 expander. For my .401 bullets, I use a .401 expander. I reason that the larger 40 caliber cases should spring back a slightly greater amount than the 9mm cases, on average. Wherever that springback is, if you are using the same expander as the bullet, it should be correct to get practically full neck tension while removing any unnecessary force on the bullet. Your bullet is getting essentially all the elastic springback, but it has to do basically none of the plastic deformation.

[44man]

Gloob, might very well be true. I like your thinking. My most accuracy has been at the bench, not at the range or gun.
Like the time a friend bought a new S&W in .45 ACP. We could not get it to hold paper at 25. I sat and stared at the rounds and told him, "too much primer for a revolver, moving boolits out." Went to small pistol cases and got groups.