varying OAL?

[icanthitabarn]

I just made my first .223's and oal's are off. They are up and down by .001-.025. The upper numbers more often. These are new Lee dies and trimmed cases. The trimming shouldnt matter, nor the Nostler 69 gr. bullets, which, after a quick check, seemed to vary by .005. My questions are, is the varying bullet lengths common? and what could cause such erratic lengths? I am thinking maybe it is a die problem or crimp is too tight. After pulling a couple, I can tell they are gripped well. I am keeping a consistent pull on the handle.

 

[LightningMan]

What type of bullets Soft points, hollow points, FMJ's ? Need more info. I suspect soft points as I load for the 5.7x28mm and have more problems holding a consistant OAL with them than any other type. For SP's I usually measure all the bullets with calipers and sort them by length and adjust my seating die as needed. LM

 

[counterclockwise]

The .005 variance in bullet length is common for some designs. The seater sets OAL by the Ogive contact normally. So even though the bullet from base to meplat varies some, the base to some reference dia. on the ogive is the controlling dimension.

Not sure about Lee dies, but the RCBS seater die has a roll crimp function. This can be disabled by screwing the die body out of the press frame by a turn, then screwing down the seater stem back to the setting that gives the desired target COAL. So now you have a round that has no roll crimp but has a COAL that you can check. Next, reverse the die action and screw in the die body, back out the seater stem, and do the roll crimp. Check COAL again. This way you can isolate the crimp effect and see if the crimp is spoiling your COAL accuracy.

In my experience with .223, I found it was necessary to do the seat/crimp in two separate steps to better control COAL accuracy.

 

[icanthitabarn]

Thanks for the responses, guys. The bullets are 69gr. hpbt no soft tip. I am thinking it may be the crimp, After the explaination. I would have thought of that method of checking.... sometime. The Lee die is just that, a die. It is a factory crimp and seater. I am now remembering the ogive reference point. Once again, I would have thought of that at some point, maybe June. Thanks to all, I feel better. I been at the workbench all day,or I would give it another try, right now. I got 47 rounds all way shorter than I wanted. I just kept reseating till all the same. Thanks again. This place is the best

 

[Walkalong]

Crimping and seating .223 in separate steps won't help O.A.L. differences, unless the brass lengths are all over the place, which his might be. If they are that bad, trimming is the best solution, even if he decides to crimp in a separate step. When I roll crimp .223, I do it in the same step. When I taper crimp .223, I do it in a separate step, because my seater will not taper crimp.

.005 difference in bullets is not uncommon. It is also unimportant. A consistent ogive is important, and I am sure that quality bullets ogive is.

Sounds like your seater stem goes not fit your bullets well, and perhaps your brass needs to be trimmed to more consistent lengths.

The trimming shouldnt matter

But it certainly can.

 

[ole farmerbuck]

I dont crimp any of my 223's. Bolts or AR. Never any trouble either. I do make sure they are a litle tighter in the necks though by polishing down the expanders. My 40g vmax's are 2.280 oal which isnt much in the case but they seem to stay put and put a hurtin on the p-dogs.

 

[twofifty]

I really don't see how case length variations can affect COL: The seating die contacts the bullet at some point on the ogive circumference and the seater pushes the bullet in till the press arm is fully cycled. The seated depth bears no relationship to where the case neck or shoulder are. So long as a round will fit and chamber from the mag, it should be GTG no matter the COL variations.

I've found that projectile lengths (base to tip) vary somewhat. However, the same bullets' base to ogive measurements are much more consistent. That latter inconsistency affects the distance to lands (not the COL) and therefore the accuracy.

In general reloading, many dimensional variations are not worth chasing to the exact thousandths or even hundreths of an inch. Some are critical.

 

[icanthitabarn]

I don't think the case length matters as to Oal, as twofifty says. I always trim to exact same length. I spent 2 hours today, grinding down a threaded cable wire stop. This goes on a piece of threaded rod which screws into the Lee cutter and when used with the newly-pointed, other end, of the threaded rod, trims very well. I made one for each caliber, for no good reason, except to use my workbench which THR caused me to make, as well as reload, fix my guns and buy a $100 belt to hold up my pants

 

[counterclockwise]

Crimping and seating .223 in separate steps won't help O.A.L. differences, unless the brass lengths are all over the place, which his might be. If they are that bad, trimming is the best solution, even if he decides to crimp in a separate step.

Combining crimping and seating on the same ram stroke which combines neck tension and roll crimp thrust and a soft shouldered case, can lead to this:



This will definitely cause a variance in COAL.

 

[icanthitabarn]

No I'm not getting anything like that. I don't think I can seat and crimp, in two steps, because I only have one die. It maybe a new thing. Its a Lee yellow box with full and neck resizer dies and the seat/ taper crimp die.

 

[Eb1]

the answer has been given. the dies set from the ogive. if you adjusted to get the OAL from tip to base you have really screwed the OAL of your cartridges.

The tip of the bullet never touches the lands. The ogive does. So think about it..... Your loads are all out of whack because you made adjustments to make them the same from tip to base.

 

[Walkalong]

Combining crimping and seating on the same ram stroke which combines neck tension and roll crimp thrust and a soft shouldered case, can lead to this: (your pic of buckeled shoulders) This will definitely cause a variance in COAL.

Absolutely it can. I've done it. Buckeled the snot out of a shoulder before.

But it is not from seating and crimping properly trimmed brass in the same step, it is from seating and crimping varying brass lengths at the same time, or just plain and simply a poorly set up die.

I said, and you quoted:

Crimping and seating .223 in separate steps won't help O.A.L. differences, unless the brass lengths are all over the place, which his might be. If they are that bad, trimming is the best solution,

 

[JimKirk]

You can't really measure COAL without something that fits the ogive of the bullet. Trying to set COAL by measuring bullet tips to base will drive you crazy(if you're a gun owner you're already crazy according to the left)! Bullet tips varies so much there is noway to do it correct. So you need something that will measure from the same point on the ogive each time. It can be something as simple as a hole drill in a piece of steel to some of the fancy rigs sold, but what ever you use it must fit the ogive. You will however have to measure the longest bullet tip to get your rounds to fit in the magazine. I use a 3/4" hex nut drilled with a 13/64(.2031) drill bit through one side of the nut. I slide the nut over the bullet and measure it with my caliper, I measure from the opposite side of the nut to base of the case . You will get a correct measurement between rounds.

Jimmy K

The photo below is from Sinclair tools and would be a good tool along with a caliper.
http://www.sinclairintl.com/product/5581/Bullet-Comparators

 

[icanthitabarn]

Update. I took a look at the stem in the seat die, that grabs the ogive, and found it not really holding the profile of this bullet, too well. It was kind of wobbling. So I fixed that. Also the die was set too deep. I followed the instructions which said to screw till the ram hits the shellholder and than 1/4 turn more. It was binding at the end of the stroke, and didnt feel right. I set it until it hit the shellholder and also took up the play in the 4 hole Lee die holder. So I loaded a few more and the OAL lengths are still different, but its a 90% improvement. I will ignore this, now. Am I correct? I also learned that the Lee yellow box set does not crimp at all, however, a die is available. The collective comments helped, although Walkalong did not completely save this caliber for me as he did for .357. Thanks again for that and also to others, with my noobyistic questions.

 

[twofifty]

Yes, you are correct, IF
-they fit and feed from your magazine,
-the action goes fully into battery,
-there are no signs of overpressure, and
-the accuracy is fine for your purposes.

Everything that man makes -whether it's a firearm from a factory, or ammo from your basement- will fall within a given set of +/- tolerances. Trying to make your rounds all exactly the same is impossible, because each component is its own entity.

You job is to make sure that when these pluses and minuses stack up, your setup remains safe and reliable. Once your sizing, seating and crimping dies are set up to give you safe and reliable rounds, you're set. Keep an eye on things (dies occasionally lose their setting) with a case checking gauge, and now and then look at your empties for signs that something is off.

 

[243winxb]

Lee's instructions

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.



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.

[/QUOTE] http://www.leeprecision.com/cgi/faq/index.cgi If Lee dont know who would.

 

[243winxb]

wrong die set info

 

[243winxb]

Lee yellow box set does not crimp at all,

Dead Length die adjustment

Make sure that you have the bullet seating die adjusted down so that the shell holder contacts the base of the die when the ram is raised to the top of its stroke. The Deluxe die set comes with the Dead length bullet seating die, which does not crimp the case, and is designed to be adjusted that way to eliminate clearance in the press for a more uniform bullet seating depth.

Dead Length Bullet Seating Explanation

The idea behind the floating bullet seater plug or "dead length bullet seating" is as follows; If you look inside the bullet seating die, you will see a restriction about 3/4 the way to the top of the die. This restriction is only .001 larger than bullet diameter, and is positioned so that when the bullet starts to seat into the case, the bearing surface will be passing through this restriction.

The bullet seater plug, being free to move axially, and due to the shape of the cavity will find the center of the nose, and a properly prepared case will find the center of the base of the bullet. The die should be turned in to touch the shell holder and is designed to be adjusted that way to eliminate clearance in the press for a more uniform bullet seating depth.

Most case/bullet alignment is determined in the resizing die. If the case neck is sized too small, the bullet will actually resize (open back up) the case neck when it is seated. If the case neck is thinner or softer on one side (and they usually are) the bullet will push out more on that side. Excessive crimp or an out of square case mouth can also cause bullet run out.

 

[icanthitabarn]

Thanks for looking that up, 243Winxb. I think I understand whats going on here, now. I can't crimp and maybe that's ok. I used the bullet puller to loosen all previously set rounds and set all to a standard length. I skipped the caliper and made index marks on the die, to judge and reproduce OAL. Even after moving the bullets, they are still gripped well. Now I am back with a question. I guess that I can live with the varying OAL's, based on the ogive setting the length, but I checked some Hornady factory rounds, with basically the same bullet profile and weight, (and supposedly a varying distance from ogive to tip) and they got their OAL's all the same. Are the Hornady bullets more consistant than the Nostlers? or is my Lee dead length die superior to the Hornady factory set-up. Anyone can set a consistant OAL, if the ogive to base measurement is not a concern. (ie me a while back)

 

[rjbishop]

I set it until it hit the shellholder and also took up the play in the 4 hole Lee die holder. So I loaded a few more and the OAL lengths are still different, but its a 90% improvement. I will ignore this, now. Am I correct?

Make sure you take up ALL of the play in the press. This is why Lee recommends you turn the die in one quarter turn after contacting the shellholder. The press may feel like it's "binding" at the end of the stroke- but you want it to bottom out for sure. Just don't slam the handle down- gentle yet firm. I get very little variation in OAL using Hornady and the Lee Turret press.

 

[Bass Ackwardz]

I just picked up a Lee Factory Crimp Die to go with my set of .223 dies. It really makes a difference if you are loading for an AR.

Bass

 

[icanthitabarn]

Yes that 1/4 turn extra seems to be the ex-problem. I later took ALL the play out and locked it. Now it isn't binding. Maybe the Hornady bullets are more consistant than the Nostler, I was wondering what others thought.

 

[JimKirk]

Hornady and Nosler bullets are really good. I don't think either would be better than the other or even other brands. I sure as with all makers there are bad bullets made and normally quality control catches the bad ones. But in this high demand time, there may be more slips than in the past, but I doubt it.

Jimmy K

 

[ole farmerbuck]

I just picked up a Lee Factory Crimp Die to go with my set of .223 dies. It really makes a difference if you are loading for an AR.

Bass

In what way? Just asking.

 

[icanthitabarn]

As to a factory crimp die, I will probably end up with one, but maybe not. It should be noted that the total lack of crimping, with the deluxe set, doesn't seem to matter. When I loosened a bunch of first made rounds, there was a very tight grip on the bullets. I think Lee may be on to something, as any more crimp is not needed.