Lee bullet seating die isn't giving consistant OAL

[hokeyplyr48]

I have my Lee bullet seating die and it isn't giving consistant OAL. My brass is from 1.477-1.451 also because the Lyman trimmer isn't consitant at all either. (truly a POS, can't wait till I get my giraud)

The bullet seating is varying from 2.234-2.253. Is this variance because of the brass? It doesn't seam like it would because the measurement should be from the base of the shellholder to the top of the inside of the die. This isn't changing but the OAL is.

Is this correct? If so, can you recommend a die that will give precise seating depths for a specific OAL?

 

[docsleepy]

Hi,

First, what cartridge is this? I missed that.

Second, your variation in case length seems excessive, I agree. I use the simple Lee trimmer for .223 and 38 special. It works well. You turn until it no longer "bites" and the lengths are consistent within a thousandth or so.

If you have the Lee trimmer, I'd suggest you try it.
Remember the Lee bullet seater is going to set the distance from the cartridge holder (bottom) to the OGIVE (where the bullet begins to get smaller, basically), NOT to the tip! Bullets are not all the same. Some have a slightly different radius to them.

On my .223 Sierra bullets, it was not uncommon to have a difference in overall length of up to .007 or so. I found that Hornady's were somewhat more consistance in THAT aspect.

I was using a more expensive bullet seater but I think the Lee is likely to do about the same. I use the Lee for .38 special.

So first I would work on your trimming problem (suggest Lee) and THEN see if the OALs haven't become more consistent....that is , if you are using match grade bullets. If you are using lead or something that is not consistent perfectly from OGIVE to tip, then it is to be expected that your overall lengths will be out ofwhack.

Hope this helps.

 

[Lee Roder]

You don't specify what you are loading or how your inconsistency arises (e.g. "early" seated less deeply than "late" loads) so this is just a guess but your seating plug may not fit your bullet. Lee will make you one for a few bucks and a few bullets; details are on Leeprecision

 

[hokeyplyr48]

I was loading .223 remington with mixed headstamps. Primarily Rem and P-R

I found out that the difference in OAL was because of the variances in case length. Measuring the OAL and comparing it to the case length returned equal distances. So it looks like it came down to a trimming problem.

I'm using Nosler 69gr HPBT which I would consider to be of decent quality so I wouldn't think the variances would be that much.

Until I figure out the trimmer problem, it's looking like I'll be measuring each round with the calipers...oh boy.

 

[Mags]

Its not P-R it is R-P and it is Remington. You should really buy this Lee Trimmer. Link for Case Gage. Link for trimmer.

 

[Ol` Joe]

I'm using Nosler 69gr HPBT which I would consider to be of decent quality so I wouldn't think the variances would be that much.

measure a couple of those bullets and you may be suprised.
The seater works as said earlier off the ocgive of the bullet, or it should. If you were to measure the col from base of cartridge to bullet ogive I doubt you`ll find much if any difference in lenght. This is most often the important lenght anyway, the point the bullet contacts the throat is based on it.

 

[docsleepy]

What gun is this for?

If a semi auto, you may want to stick with fixed distances specified in the reloading book.

If this is a bolt, and you are able to measure the distance to the "lands" you may actually want to position the bullet out somewhat. Many find that between "jammed on the lands" and .020 off the lands works well.

Tell us what gun you are loading for and can give you better advice.

 

[WNTFW]

Hokey,
Maybe I have been lucky. My seating has been fairly uniform regardless of the dies or bullets used. I have used only Lee trimmers like The Real Mags linked except for a Giraud. Debur of course.
On .223 mixed brass I did find using a good lube made a difference. I could not get OneShot to give good results & others swear by it. I use Dillon dies on a .223 & SofSole mink oil (not Kiwi) available at Acadamy Sports. The mink oil really made a difference on sizing, based on fitting a case gauge.
I used a borrowed Giraud - Slicker than greased mink Oil. Did about 8k of .223 in a week in my spare time.

 

[gearheadpyro]

I also had issues with inconsistent C.O.L.'s when using my Lee bullet seating die. You could watch the adjustment knob go up and down when I put the cartridge in. I switched over to a Redding Competition Seater ($$$ I know), Haven't had a lick of trouble since. Also make sure you are measuring from the ogive when you measure C.O.L. As previously mentioned tip to base length can vary quite a bit.

One other thing I had when I first got started, I was using a lee turret press and the head would shift differently from cartridge to cartridge also aiding in my inconsistent C.O.L. problem.

Don't misunderstand me. I love Lee products. I still use my turret press for my handgun loads, and I use a Lee bullet seater die for those as well. I just think Lee has purpose built products, and I was using them for the wrong purpose.

 

[Walkalong]

Is this variance because of the brass?

No.

It is not uncommon for the O.A.L. to vary a good bit. The seater contacts the ogive when seating, it doesn't push on the tip. How far the ogive is off the lands is more important than O.A.L.. If that distance is consistent, you are good to go. You can not measure that with calipers alone. They do make various tools to do so though.

I use a Possum Hollow trimmer for .223 brass, and it works great.

 

[BullfrogKen]

Are you using a progressive to load them?


I've noticed some progressive presses will load the first round a little deeper, then load consistent lengths when all the stations are full, and then load the last one through deeper, because the other stations are empty.


Also, when you first adjust the die to seat the first round, there's usually a bit of

• stroke the press -
• measure -
• adjust -
• stroke the press again -
• measure again -
• adjust again

until you get the right depth. Once fully adjusted, the next pass through won't seat as deep. It's just got to do with incrementally seating the bullet vs. doing it in one stroke.

There are probably several factors involved with why you aren't seeing a consistent OAL, but these two are the most common. And remember, the length to the tip of the round isn't nearly as important as the internal case capacity and the length to the ogive. Measuring to the tip doesn't guarantee the others are off, or that they're on. It simply assumes that each bullet component is the same overall length and that the length to the ogive is the same.


Usually OAL is a "good enough" measurement. And it's important to ensure they'll seat in a magazine. Besides that, OAL is merely a good indicator of where those other two, harder to measure lengths lie.


20 bucks says it's a result of one, or the combination of both of those factors I mentioned - having empty stations on a progressive and not checking what the press will kick out in actual OAL once you initially adjust it.

 

[mhat]

invest in a bullet comparator. I think that will answer the OAL question.

 

[hokeyplyr48]

I was under the impression that OAL was important in determining accuracy and consistency between shots.

Also I was stroking, measuring, adjusting, etc. so I guess I'll try the all in one stroke and see if that changes. (sounds like I'll be giving my bullet puller a workout)

Also it's being loaded into an AR, but I want accurate loads for long range (out to 500)

 

[BullfrogKen]

OAL is merely one way to measure, but it assumes the length to ogive and OAL of each bullet in your batch is the same. Assuming they are, OAL works as a good way to determine those measurements.


I always work up the depth on a round first. Then, after those cycles of stroke, measure, adjust I run another two or three straight through in one pass and measure them.


Are you using a progressive press?


I don't go back and pull anything unless it's way out of spec, the round is a compressed charge, or the pressure is high enough that too much depth spikes pressure exponentially. Otherwise, I just shoot it along with the rest.

 

[hokeyplyr48]

I'm using a turret, basically a single stage in this case.

But I'll try your methods in the morning and see if that corrects my issue. I also think it's partialy due to the difference in length of brass. This could affect it right?

 

[BullfrogKen]

It could.


If the other factors aren't at fault, try not seating and crimping in the same step and see if that solves your problem.

 

[hokeyplyr48]

Well I just bought a Hornady comparator so once that arrives I'll measure some to see if the oal from the ogive is varying versus the total OAL from the base of the case to the tip.

I'll also load a few with one pull instead of adjusting with each pull to see if that helps (after I trim some more brass that is consistently the same length)

 

[ranger335v]

"Lee bullet seating die isn't giving consistant OAL....the Lyman trimmer isn't consitant at all either. (truly a POS,"

The seater just sits there, it has little to do with OAL by itself. Inconsistancy in OAL is usually a flex problem in the press or, much more often, inconsistant press operation.

Likewise, inconsistant trim length with my Lyman trimmer is dependant on operator consistancy. If your longer cases are off by some 25 thou you stopped too soon OR you don't have the shaft travel stop properly secured. No other explanations are possible. ??

 

[rcmodel]

If you are using mixed headstamp cases I would not stress out over inconsistent OAL or anything else.

There is enough difference in internal case capacity/pressure differance in mixed brass to blow anything else you do in the search for accuracy out of the water.

It could also contribute to your other problems with seating and case trimming.

Different brass hardness, neck thickness, and other differences make doing anything with mixed brass inconsistent.

rc.

 

[woods]

+1

The press has linkages and different seating pressure will cause a different seating depth. Next time you are seating a set of bullets and one takes more force to seat, measure the OAL and you will find that it is longer (even if you have a comparator and are measuring to the ogive).

Sometimes the bullets themselves have a large variance in the bearing surfaces, especially if you mix bullets from several boxes. I noticed this recently and had a variance of .018" in a bunch of 200 gr Accubonds and a variance of .021" in a bunch of 180 gr Accubonds. I am guilty of mixing boxes of bullets though (not anymore).

To stabilize the seating pressure you have to control the inside of the neck diameter and surface completely. Also the hardness of the neck. If you load a several times fired case and compare to a new or freshly annealed case, the several times fired case will have different springback and offer different resistance to seating pressure.

It's a complicated thing but I have gotten my seating depth variation down to less than .002", as measured with a comparator, through a series of procedures and it has stabilized my velocity to single digit variation and helped my long range groups.

 

[Bullet]

If you’re loading for an AR then you don’t need a comparator. You are loading to fit in the mag. Don’t mix brands of cases or bullets. Take one case and bullet and set your seating die so that the OAL is .005 longer than the max listed in your manual. Then load 50 rounds (with NO crimp). Once you’ve loaded 50 rounds measure them with your calipers for the OAL from the base of the case to the point of the bullet tip keeping track of the one with the longest OAL. Once you find the one with the longest OAL you then can shorten it by adjusting your seating die to achieve the max OAL listed in your manual, which will fit in your mag. Your seating die will now be set for the bullets you are using. Now run all the rest of the 50 rounds you loaded back through the seating die again. At this point you can crimp your cartridges if you use bullets with a cannelure. The OAL measurement will vary but all your rounds will fit in your mag and the ogive will be a pretty consistent distance to the lands. When measuring to seat a bullet close to the lands a bullet comparator can be handy but to load to fit in a mag it is not needed. If you change bullet weights or brands you will have to start over from the beginning because the shape of the ogive will be different.

 

[243winxb]

Seating depth variations

There are a number of possible causes for overall length variation. One is the way it is measured. If you measure overall length from the tip of the bullet to the base of the case, remember to subtract the variation due to bullet length tolerance. The bullets will vary in length due to manufacturing tolerances (bullets with exposed lead noses are the worst in this regard) and this will add to the overall cartridge length variation. Remember that the bullet seater plug does not (or shouldn't) contact the tip of the bullet when seating, but contacts farther down the ogive. For a more accurate seating depth measurement, take the seater plug out of the bullet seating die, place it on top of the cartridge and measure from the base of the case to the top of the seater plug.

Another possible cause for bullet seating depth variation is seating and crimping at the same time when trying to apply a firm crimp to untrimmed cases. Variation in case length also causes variation in the amount of crimp applied. Long cases get a heavier crimp than short ones. When seating and crimping at the same time, the crimp is formed as the bullet is seated into the case. The crimp will form sooner on a long case, and therefore the bullet will not be seated as deeply. The solution is to seat and crimp in a separate step, and/or trim cases to a uniform length.

The amount of force required to cycle a progressive press varies with the number of cases in the shell plate. When the shell plate is full, it is harder to lower the lever than when there are one or two cases present. This can lead to variation in cartridge overall length because there are different loads placed on the working parts of the press. When the shell plate is full, seating depth will be slightly long, because the load is higher and all of the clearances are taken up. With the shell plate nearly empty, the load is not great enough to squeeze out these clearances, and the seating depth is short.
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