Need help solving concentricity problem

[wallenba]

Recently I got a new Saeco #081 mold for my K98. It drops beautiful boolits at
.324 to .325 at the lower band, but the upper checks .326-.327. My Mauser slugs at .323, they don't make a .324 for my sizer so I have to size them at .323 to true them up and lube and gas check them. (I tried lapping out a Lee .323 but messed it up) After lubrisizing I found the concentricity way off, as much as .007-.008. Attempts to straighten them failed (Hornady concentricity gage). I pulled them and put them between the jaws of a dial caliper and slowly rotated them and found that the axis of the boolit body was different than the driving bands. Unsized boolits are OK. My alloy is Lyman #2, and it works well in similar size boolits in my Mosin, so I don't think they are getting bent from being too soft. One clue I do have is that they seem a little difficult to start in the sizing die leading me to believe that it is tipping in the die. What would cause that and how can I correct it?[smilie=b:

[grouch]

It sounds like you're better equipped than me to solve the problem, but I think Lee will custom make one of their sizers any size you want. If you're a machinist, you could make one yourself. The nose first design, hopefully will size your bullets more concentrically
Grouch

[John Boy]

What would cause that and how can I correct it?
Dutch, are you using a Lee Lube Sizer (bottom - up) or an H&I L/S (top - down)
If the Lee, they can cut you a 324 die for $25

Going from 327 to 324 in one pass is messing up the concentricity ... too much squeezing
Do it in 2 passes (327 to 325) and then 324

[cbrick]

You didn't say what lubrisizer your using but as was mentioned a straight through, nose first method does give more concentric bullets. It is one of the prime reasons I use the Star.

You may not need to size down to .323, .325 may work as well or better if it chambers and that's only .002" sizing.

Rick

[JIMinPHX]

I had some noticeable eccentricity issues when pushing some very short 9mm-Mak boolits through a Lyman 4500. My solution was to size them nose down with a flat top punch. That kept them straight. Alternately, running them through a push through sizer first, to get them down to size, then lubeing with a sizing die that is .001" oversized, also works well, but adds a step to the process.

[wallenba]

You didn't say what lubrisizer your using but as was mentioned a straight through, nose first method does give more concentric bullets. It is one of the prime reasons I use the Star.

You may not need to size down to .323, .325 may work as well or better if it chambers and that's only .002" sizing.

Rick


I am using a Lyman 4500 and I have a .325 on order from Midway, but as the bottom band is below .325 the neck of the case would only firmly support the upper band. I'll try sizing upside down as JiminPHX suggests, but I will have to reverse again to gas check it. I recently had a similar problem with a tall 205 grain Lyman 314299. It was bending during sizing. I tracked that one down to an NEI top punch I decided to use. It was actually bored off center (one of many problems from NEI lately). I did try lapping a Lee .323 but it came out, out of round.
My next solution is the Lee C324-175-r mold. Some of the reviews on it say they drop around .325, but I hate to give up on the expensive Saeco mold.

[wallenba]

Going from 327 to 324 in one pass is messing up the concentricity ... too much squeezing
Do it in 2 passes (327 to 325) and then 324

I think you are right about that, and I have ordered a .325. I will look at the Lee site for info on custom sizer too. It seems that every time I get a new rifle or gun to cast for, some challenge arises. I have a Ruger Blackhawk 45 Colt that I have to tackle next, .451 bore and .451 throats...DOH!!

[HORNET]

Dutch, are you leaving the top punch loose and letting a dab of boolit lube keep it in the ram? Lyman used to kick out a lubrisizer once in a while that didn't have the ram concentric to the bore for the sizing dies and the loose technique helped some. Yours could be out of whack a bit which would have helped compound the problem that you had with the 314299 that was bending.

[wallenba]

Dutch, are you leaving the top punch loose and letting a dab of boolit lube keep it in the ram? Lyman used to kick out a lubrisizer once in a while that didn't have the ram concentric to the bore for the sizing dies and the loose technique helped some. Yours could be out of whack a bit which would have helped compound the problem that you had with the 314299 that was bending.

That might be contributing to it too. I substituted a top punch that pressed on the very point only. It flattened the point a bit, but it came out STRAIGHT! I'll try the loose method next. I never noticed a problem with my pistol boolits, but with those being wad cutters or semi wad cutters it would not have been as visually apparent a problem.

[cbrick]

Hornet brought up an interesting point. On the Star machine there is a lock nut that locks down the punch after it's adjusted, I have never used it. I adjust the punch and leave it free float. The flat punch centers flat on the bullet base and starts the bullet into the die straight without any possible mis-alignment of the punch.

Rick

[wallenba]

Hornet brought up an interesting point. On the Star machine there is a lock nut that locks down the punch after it's adjusted, I have never used it. I adjust the punch and leave it free float. The flat punch centers flat on the bullet base and starts the bullet into the die straight without any possible mis-alignment of the punch.

Rick

Funny that you brought up the Star...I just got off the phone with Magma Engineering. I broke down and ordered one and some dies for my Mosin and Mauser. Had to get specific top punches for gas checking too. I have to wait 3-4 weeks due to a part shortage of some kind before they can ship, but I can stop pulling my hair out over this. I already have a Lyman heater that is drilled for it and is mounted on one of Pat's RockDocks so I can mount it right away.

But honey!! look at all the money I save making my own boolits![smilie=l:

[geargnasher]

Wallenba, you've just discovered the major shortcoming of the Lyman 4500. Well, one of them, anyway. The short guide for the ram doesn't support the ram evenly, and you can easily get bent or out-of-round boolits with it. Use a push through or the Star when you get it. You can gc and size at the same time in a push-through.

JiminPHX does exactly what I do in a couple of different situations, it works well.

Gear

[cbrick]

Had to get specific top punches for gas checking too.

Huh? :shock:

Did you order top punches or flat punches for nose first sizing?

That's new to me. I use a flat punch to both size and install the checks at the same time.

Specific top punch? :-? :confused: :veryconfu

Rick

[wallenba]

Huh? :shock:

Did you order top punches or flat punches for nose first sizing?

That's new to me. I use a flat punch to both size and install the checks at the same time.

Specific top punch? :-? :confused: :veryconfu

Rick

I don't know exactly why, but when I asked the woman who took my order on the phone how well it applied gas checks, she replied with " I'm glad you asked that because a different punch should be used". From what I gather it needs a specific diameter for each. It might be that one the size of the gas check bottom rim will ensure that it does not 'bend back', that's all I could figure, don't know for sure. She just told me the techs would figure out what I needed. I didn't question it further, I figured they know their business, and would get it right for me.
I assumed that she knew I was going to size nose first in the die. Hmmmm.

[cbrick]

Kinda makes sense except there is no need for two punches if that's what she meant. When I need a new punch, which isn't often anymore, I just automatcally order the largest diameter that will fit into the dies in question without touching/rubbing the sides of the die. Just a few thousands under the marked diameter of the smallest die in a given caliber. Both sizes and seats checks flat against the bullet base in one step.

Another thing to know about ordering dies from Magma, when they ask how many lube grooves your bullet has tell them 4. If you say 1 if that's what your bullet has, they will sell you a die with one row of holes. Down the road you get another mold in the same caliber that has more lube grooves and you get to order a new die in the same diameter. Far better to get a die with extra rows of holes and plug the un-needed ones. Good way for them to sell more dies but not too good for you. I can't swear they do this on purpose but . . . They did it to me, but just once.

Rick

[wallenba]

Rick, good tip on the die holes. I am going to call back Friday to verify about the punches and maybe get some extra holes added. They did want to know the spacing on my .314 & .315 molds, but my Saeco 8mm is a single.

[wallenba]

Wallenba, you've just discovered the major shortcoming of the Lyman 4500. Well, one of them, anyway. The short guide for the ram doesn't support the ram evenly, and you can easily get bent or out-of-round boolits with it. Use a push through or the Star when you get it. You can gc and size at the same time in a push-through.

JiminPHX does exactly what I do in a couple of different situations, it works well.

Gear
Thanks Gear, I had no clue it had that issue. I can see the geometry of it now, and can see that the longer the boolit, the worse it will be. I never would have figured that out. I was convinced the top punch alone was the culprit. Does the Lube-a-matic suffer the same limitation? It's very similar in design.

[cbrick]

Don't forget about Lathesmith when you need Star dies. I haven't needed a new die for some time, I already have about 35 Star dies across many calibers, but the next ones I get will be from him.

The Star Dies That I Make (http://castboolits.gunloads.com/showthread.php?t=34499)

Rick

[noylj]

Before doing anything, remember these are cast bullets and they can be significantly larger than groove diameter and perform exceptionally well. Use a sizer that is the same or no more than 0.002" larger than your bullets and lubricate them. If you find that you have to size them (I have never found this, but you might), get a Star or Lee sizer. I have never found that sizing any of my cast bullets ever improved accuracy or minimized leading.

[geargnasher]

Thanks Gear, I had no clue it had that issue. I can see the geometry of it now, and can see that the longer the boolit, the worse it will be. I never would have figured that out. I was convinced the top punch alone was the culprit. Does the Lube-a-matic suffer the same limitation? It's very similar in design.

You'll never notice it with short, fat pistol boolits, but try partially nose sizing a Cruise Missile sometime and any play in the ram will make itself glaringly apparent. Not knocking the tool, I just got one of my own last year and lube many hundreds of boolits a month with it, but I use an old Lyman 45 for rifle boolits or push through in a lee and lube/check in either the 45 or 450. I have no experience with the LAM.

Buckshot has a "fix" for worn-out rams, but IMO rebushing the thing is the only real fix, and it will wear out soon enough. Push-through Lee or custom dies and a press with a good, solid ram (or, again, the Star) will solve your rifle boolit issues.

Gear

[wallenba]

Gear, yep. With the ram at the top of the stoke I can visually see it tip forward at least 3 or 4 degrees. It must be ovaling the bore, top front and bottom rear. I did order the Star this morning, so the Lyman will be for small rifle and pistol from now on. I think that the way the linkage articulates it is unavoidable at the extremes, but will be OK from the middle down.

[wallenba]

I called back Magma Eng, today to ask again about the punches for gas checking. They do indeed make special high tolerance punches for gas checking that are closer in diameter to the die size to ensure a better seat. They do not normally supply them unless asked.

[JIMinPHX]

Another thing that I sometimes do is to make up a custom die with a pilot bore that is about .005" over the finished size, that then tapers down to finish size. The larger pilot diameter area guarantees that the boolit will be straight in the die when it hits the sizing area.