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abcollector
06-23-2010, 09:04 PM
I was sizing some cast .432" diameter bullets the other day to .431" with a RCBS sizer and noticed that the point where the bearing surface meets the ogive is not even all the way around. Another words, some areas are higher than others. I've noticed this on some other bullets but not to this amount. The bullet style is LFN.

Is this normal or how can I go about fixing it or reducing the severity of it? I did try "floating" the nose punch and sizing die but that didn't fix it though it helped a tiny bit.

Any other ideas?

Thanks guys.

HeavyMetal
06-23-2010, 09:11 PM
Nose size with a Star and there is no issue with concentricity.

What you are experincing here is the inherent misalignment of lube sizers. Lyman are famous for it I have heard of an RCBS or two as well.

This mis alignment is the reason that the Seaco punches are designed a little different and are a little more expensive.

In the Saeco the punch screws into the top of the sizer and then the "cone" part of the punch centers it in the threaded hole.

If you can find a good deal on a Saeco buy it! It is the next best sizer on the market right behind the Star.

dragonrider
06-23-2010, 09:47 PM
It's one reason I now use only my Star. Retired the Lyman. And the speed of the Star would be a factor as well.

abcollector
06-23-2010, 10:42 PM
That's what I was afraid of... but was hoping I overlooked something a little easier to fix. With a Star sizer, can you use it with gas checks?

Back to the RCBS sizer, as popular as they are, what do other people do to coop with the issue? Are some bullet profiles more likely to suffer from this "misalignment" than others?

Why can't things be simpler?

HeavyMetal
06-24-2010, 01:03 AM
If your going to stick with the RCBS sizer, no matter what the reason, heres what I would do:

First get a small group of each boolit you wish to lube and size

then strip the "Pin" (I die?) out of the H die in the sizer.

Then insert your boolit nose first into the die and push it through until it comes out the bottom of the H die. Be aware you will have to put several through it to start getting them to come out the bottom. You may have to remove parts of the ram from the press to get the machine to do this. I have done this successfully with an old Lyman 45 but never attempted an RCBS sizer.

Once you have several nose sized boolits pull the H die from the press and insert one of these "choice" boolits back in the die so the nose points up , or out the top of the H die.

The ideas is to get a concentrically sized boolit with the nose sticking up out of the H die far enough that you can bring the top punch down onto it.

Now comes the tricky part. The straight shank top punch's are the weakness in this design. The shanks are never a tight fit and the set screw all ways pushs then out of alignment!

If you can have some one turn you a blank top punch or two with the shanks an actual push in fit in your sizer, then have them cut the section that fits the nose of the boolit very deep and wide

You turn the sizer up side down insert the H die with the boolit sticking out of it and coat it with a release agent like you'll find in an acra glass kit, mix up some JB weld or any good 2 compound 5 minute epoxy fill the extra large "hole" in your custom top punch and then lower the boolit into the glue until it hardens!

Now you will have an exact, made for you sizer only, top punch that should maintain alignment when sizing in the "standard" manner.

The up side is increased accuracy the down side is this is just annoying to have to do for more than one or two boolits!

Be careful with any epoxy around your sizer and make sure you compensate for "over fill" when you put the liquid epoxy in the top punch, you don't want it runnng down the sides of the top punch!

Hope this idea helps you out.

Hang Fire
06-24-2010, 02:07 AM
Check the top punch, doesn't have to be off much to start the boolit wrong. Might try rotating the sizing die to see if that helps. I know with my old #45 Lyman and big boolit dies, if one gets western when tightning the allen set screw, the die can be deformed a little.

I read where some guys with similar problems size their boolits through the Lee nose first push through dies then lube with their base first Lyman/RCBS units.

Buckshot
06-24-2010, 02:14 AM
...............Don't feel like the Lone Stranger abcollector :-) Check here: http://castboolits.gunloads.com/showthread.php?t=945

For what the extra cost it would entail, I fail to see why Lyman or RCBS don't simply provide hard chromed rams riding in solid bronze sleeves with felts top and bottom.

..............Buckshot

Bass Ackward
06-24-2010, 06:17 AM
I was sizing some cast .432" diameter bullets the other day to .431" with a RCBS sizer and noticed that the point where the bearing surface meets the ogive is not even all the way around. Another words, some areas are higher than others. I've noticed this on some other bullets but not to this amount. The bullet style is LFN.

Is this normal or how can I go about fixing it or reducing the severity of it? I did try "floating" the nose punch and sizing die but that didn't fix it though it helped a tiny bit.

Any other ideas?

Thanks guys.



Fix it? Why sure. Run it through a nose first sizer. The one that has rifling in it.

It'll round out if that tube is round. Good chance that that tube isn't as close as your sizer. But after you put that slug through it's environmental transformation and it whacks something, that visual effect will be gone anyway.

quack1
06-24-2010, 08:22 AM
I do the epoxy in the drilled out top punch like heavymetal, with a couple added steps for my
old Lyman 45. First I put a centerpunch dimple on the edge of the sizer die and line it up with the setscrew that holds the die in. Then I put another centerpunch dimple beside the top punch hole and a dimple on the top edge of the top punch shank. I line up those 2 dimples, line up the dimple on the sizer die with the setscrew, then add the epoxt to the hollowed out top punch. I do this for all my sizer dies and top punches. Being able to put the sizer and top punch in with the same orientation makes for perfect alignment every time.

dragonrider
06-24-2010, 08:54 AM
Yes to gas checks in the Star, seats them very well.

45r
06-24-2010, 10:18 AM
I run my boolits through a lee first.I run them through again to wipe lube off bands also.gives better neck tension.My lee is 1 thou less diameter.I usually heat treat boolits before lubing.They're hard and don't get messed up by any lubrisizer issues.

cbrick
06-24-2010, 02:19 PM
Several years ago I took several 7mm boolits to friends machine shop and checked concentricity on a comparator. The boolits had been sized in a Star, a SAECO and an RCBS (didn't have a Lyman). The differences were astounding, the RCBS and SAECO had very little difference between them. I didn't even have to keep the boolits separate to pick out the Star sized boolits, the difference in concentricity was that dramatic.

Boolits that far off center enter the bore that far off center pushing lead more to one side than the other. Of course it does, it's already on one side more than the other. Don't think for a second that just because your boolit enters the bore it's now magically nice and round and concentric. When that boolit leaves the muzzle like this (non-concentric/out of balance) there goes your group. Yes, I did group test this, non-concentric boolits do not group as well as concentric boolits. After this testing, both with the comparator and at the range, I haven't sized a boolit in anything except the Star. Speed is only part of the reason to use a Star . . . Speed, concentricity and no lube on the boolit anywhere except the lube groove.

Yes, of course the Star seats gas checks.

I suspect the Lee push through dies would have similar results but I haven't tried the lee's so can't say for sure.

Yep, RCBS, Lyman and SAECO machines will size and lube your boolits, I guess it all depends on what your looking for and willing to accept.

Rick

Echo
06-24-2010, 03:57 PM
Hmmm - How concentric are the boolits before you run them through the sizer? Is the extra length on one side only?

StarMetal
06-24-2010, 04:23 PM
There are too many members shooting exceptionally small groups in various rifle calibers, some of us in fast twist rifles at high velocity. If the RCBS and Lyman sizers are that "bad", how can that be?

If you fellows decide that you want to sell you "no good bullet bending Lyman's and RCBS" sizers I'll be glad to buy them. I'll sell them on Ebay and make a bundle.

Seriously there are reasons for bending bullets in those type sizers. One is the sizer itself may not be in perfect alignment. Buckshot mentioned something about why don't they make them such and such way. A trick to help the sizer to center a bullet is to let the top punch free float. Don't clamp it down with the set screw. Put a dab of stiff tacky lube on it. I've been doing that for years.

Next don't size the bullet excessively. If it needs to go down a lot do it in steps. Bullets are easier to size before they age so size them asap after casting. Try see that your gun will let you shoot a bullet that is loaded as it drops from the mold. That's best. If possible try using a sizer die that merely crimps the gas check and lubes the grooves without much sizing done to the bullet.

I'm getting too good of groups with long skinny 6.5 bullets to have a luber/sizer that is bending my bullets. So are others.

cbrick
06-24-2010, 06:56 PM
Hmmm - How concentric are the boolits before you run them through the sizer? Is the extra length on one side only?

Length has nothing to do with it, it's more lead on one side than the other or non-concentric.

StarMetal, didn't read in this thread anywhere that said they "that bad". I do believe the Star is that good though, settle for whatever you wish.

Didn't read anywhere here where it said anything about "bending bullets".

Anything else you'd like to add that's not in this thread?

Rick

StarMetal
06-24-2010, 07:23 PM
Length has nothing to do with it, it's more lead on one side than the other or non-concentric.

StarMetal, didn't read in this thread anywhere that said they "that bad". I do believe the Star is that good though, settle for whatever you wish.

Didn't read anywhere here where it said anything about "bending bullets".

Anything else you'd like to add that's not in this thread?

Rick

If a bullet isn't round, and none of them are perfect, no sizer is going to size them symmetrical. Only thing then would be to run them into a swager.

Now if that nose is where it looks like it is sizing different around the circumference, then maybe the that part of the mold isn't just right. Another thing is if the sizing is hard the bullet compressed if it has to be forced even if you can't see it and that usually takes place at the nose area. There is enough slop in the Lyman and RCBS sizers and being most dies now have a gentle lead in to their bore, I see no reason for the sizer machine to size it off center.

A long bullet can bend and make it appear it wasn't symmetrical after it was sized.

BTW I was kind of catching two threads at one time. The other one kinda gives the virtues that the Lyman and RCBS sizers are junk which they are not. I was also giving my opinion and experiences on what I have observed over the years. I wasn't flaming anyone in the thread and I really don't understand what your problem is with my post. Just trying to help. :drinks:

Hang Fire
06-25-2010, 01:39 AM
"Next don't size the bullet excessively. If it needs to go down a lot do it in steps."

StarMetal you may have been referring to using different diameter sizing dies and you are right on that, long boolits are especially susceptible to bending. When doing some of the tricky ones that are being reduced only a little but still go hard in just one die, I size a little, back out and then a bit more, sometimes making 4-5 runs at it. If done in a one stroke pass, some bent boolits are almost a sure thing for me.

Pat I.
06-25-2010, 03:35 PM
Unless you're using an LBT style bullet there's really not much chance of finding out if your lube sizer is sizing concentric or not. I predominantly use LBT moulds so after seeing the poor results using a lubesizer starting sizing in a Lee die and using the lubesizer with a die .001 over sized diameter to apply the lube. Adds a step but with all the other time you spend getting a bullet from ingot to something usable it isn't that bad.

abcollector
06-25-2010, 05:55 PM
Pat I, I think you hit the nail on the head there. I did say I was sizing a LFN which in this case is a LBT bullet. I have found that it's hard to get an even line around the bullet at the end of the bearing surface and beginning of the ogive. I just wanted to see if there was something more I could do/try to limit it. I looks like a Star is in my future.

I will have two RCBS Lube-A-Sizers II for sale. One is like brand new that I modified from the sliding bar pressure screw to a ratchet style similar to the original Lube-A-Sizers, and the second one is in excellent shape with some paint coming off around where the sizing die nut screws into the body. Both are cleaned of lube and are ready to go.

Echo
06-25-2010, 11:18 PM
My comment about higher/taller/whatever on one side was aimed at the sized area of the boolit. If it was symmetrical, that is, the same height on one side as on the other, then I would think the boolit was figure-8 shaped as it came from the mold, and the sizer just rounded it up.
On the other hand, if the sized portion was higher on one side than the other, that indicates some misalignment between the nose punch and the H/I die.
So. What is the diameter of the as-cast boolit across the separation line, and 90* to that line. I wouldn't be surprised if they were .002-.003 different.

mtgrs737
06-26-2010, 12:47 AM
Most of the time that I get boolits that are excessively sized on one side is because the casting was out of round to begin with. I have had them so out of round that when sized the crimp groove all but disapeared on one side due to metal displacing. I use a star for pistol boolits esclusively.

cbrick
06-26-2010, 02:02 AM
A mold far enough off center and/or has driving bands deeper in one cavity than the other that you can see with the naked eye should go back to the mfg with a very strong letter. A far more likely cause is a poor fitting, off center or misaligned top punch that cannot possibly start the boolit straight or properly center it in the die.

You can see it with the naked eye, try this, place a quarter on a sheet of paper and draw a line around it, then use a penny and draw another circle "centered" inside the first. If you hold a sized boolit, even 7mm or 30 cal boolits, with the nose point towards your eye and with a good light shinning on the nose of the boolit you can see the forward edge of the front driving band, it will show up as a shinny ring and should be even all the way around the boolit, this is what your drawing should look like. This is a concentric boolit.

Now do another drawing only this time draw the inner circle off-center but still inside the outer circle, just close to one side of the outer circle. This is what looking at the front edge of the forward driving band will look like when it's sized off center or canted in the die. Yes, a micrometer will tell you the boolit is round because it's measuring the outer circle only but that has nothing to do with concentricity. Your drawing will show this very clearly, the outer circle is round but the center of the inner circle is not the center of the outer circle. It's center of weight/mass is not it's center of axis.

Hope this helps explain it and make this a little easier to understand.

Rick

Changeling
06-26-2010, 03:15 PM
Pat I, I think you hit the nail on the head there. I did say I was sizing a LFN which in this case is a LBT bullet. I have found that it's hard to get an even line around the bullet at the end of the bearing surface and beginning of the ogive. I just wanted to see if there was something more I could do/try to limit it. I looks like a Star is in my future.

I will have two RCBS Lube-A-Sizers II for sale. One is like brand new that I modified from the sliding bar pressure screw to a ratchet style similar to the original Lube-A-Sizers, and the second one is in excellent shape with some paint coming off around where the sizing die nut screws into the body. Both are cleaned of lube and are ready to go.

From what I've read, very few bullets are round, so it stands to reason if you start with an out of round bullet, no sizer will make it a perfectly round bullet, and that makes good sense.
The LBT book mentions a way to align the RCBS lube- matic to do as well as one can with what you have to work with, witch isn't bad as "Star Metal" has already said. Some of the guys here seem to be shooting some awesome groups with there out of round RCBS/Lyman sizers and/or bullets. However, I am all for starting with "Aces" and ending up with them, then starting with "Queens" and ending up wit "10's", I think you get my drift!

So, cheery derived molds, will never be as round as lath made molds, talking "quality" here! If you have a well made lath mold relative to the dimensions your firearm needs, than there is no need for sizing other than to remove excess lube by several means.

Pat I.
06-26-2010, 03:34 PM
It's not about the bullet being round or out of round or bent it's about being sized to the centerline of the bullet. You really need to size an LBT style bullet to see what's being talked about. If it's sized to the centerline the bullet will have a ring where the bearing surface meets the ogive will be even all the way around. If it's sized off center the ring will be higher on one side than the other. What you'll end up with if it's not sized concentric is basically a cam.

cbrick
06-26-2010, 06:32 PM
A cam is not the right comparison because a sized boolit could measure perfectly round and still not be concentric. Using a micrometer to measure for "round" will not tell you if it's concentric.

This thread is not about round boolits, this thread is not about the method of mold manufacture, if one method is better than another or if they drop round boolits. It is about boolits "sized" non symmetrical in a lubrisizer.

Round and concentric are two different things. Concentric and round are not the same thing.

Rick

Pat I.
06-26-2010, 09:04 PM
I feel that the cam analogy is just about right. If a bullet is sized nonconcentric and you run a shaft down it's centerline it will work just like a cam. It's not about being round it's about how the bullet spins in comparison to it's centerline. We're saying the same thing and understand what we're saying just explaining it differently.

cajun shooter
06-27-2010, 09:27 AM
I used my first Star in 1971 and noticed that some bullets were only sized on one side and not all the way around the bullet. This told me that the bullet was not concentric when it left the mold and not the fault of the sizer. If the bullet was perfect all the way of it's 360 then the sizing marks would also be the same not on just one side. A perfect piece of .429 lead that is pushed through a perfect piece of round steel that is .427 then that bullet will show that it had been sized the entire 360 and not 180

Pat I.
06-27-2010, 10:26 AM
That's not quite what we're discussing. I wish I still had the picture from an article I wrote for the Fouling Shot a while back about this very subject. Some times a visual aid helps in explaining things. All I can say is without a LBT style bullet seeing if it's being sized concentric or not is pretty hard to do.