inconsistent OAL on 45ACP rounds

M

mofosheee

New member
It's frustrating that I am receiving inconsistent OAL measurements when reloading Berrys 45cal 230gr RN plated on my Dillon 650.

My intended OAL was set to be 1.260".

Using my Mitutoyo Micrometer, OAL measurements of loaded rounds are ranging between 1.255" and 1.270". My crimped rounds are a consistent 0.468"

This is a newer machine and I have about 2000 rounds loading experience.

What say the experts about my inconsistent measurements? Am I expecting too much consistency?

Thanks all
 
What seating die are you using? I have some Lee dies with seating stems that tend to wonder out over time. It also could be inconsistent bullet ogives.

Do the 1.27 rounds function? That's getting kind of long for 45 ACP, but if they work in your guns the difference between the rounds will be of little consequence in a 45 ACP cartridge.
 
New reloader starting with a progressive press? You could measure the length of the plated bullets to look for inconsistencies. Dies? Crimping and seating in one operation? Are you running a full shell plate or going with one round at a time; shell plate wobble? I'd remove the seating die, disassemble and clean it, make sure everything is tight and readjust the die to seat only and see what happens...
 
First thing to check is the bullets, themselves. Are they uniform in length?

.01" over to .005" under the desired length could simply be the difference in length of individual bullets between where the seating stem contacts the bullet and the tip you are using as the measuring point.

You are shooting PLATED bullets. These are not high end, precision bullets. You aren't getting (nor are you paying for) a high degree of precision uniformity.

There are other possible causes, but the first thing I would look at for the small amount of variance you are finding, is variance in the bullets, themselves.
 
I too find a continuous deviation in length when using plated bullets, Doesn't matter if they are Berry's or Xtreme and makes no difference if I load them on my progressive press, turret press or single stage press. Also find the same thing whether it's RN or FP bullets.

Right now I am finding the greatest deviation is with the 451" sized bullets opposed to the .356" 9mm and I use all Lee dies. Which dies are you using?

Oh yeah, Welcome to the forum!
 
Not sure if it would matter but you may also be putting too much crimp on those. I taper crimp to .471 with the Berrys 230 gr. RN. Just enough to remove the flare.
 
Thanks to all who responded!
Should have included this in the initial post.

1) Everything Dillon 650
2) plate snug, not loose
3) dies snug, no play
4) amazingly the bullets measure a consistent 0.634" =+/- .001. Measured 10
of them
5) crimping to 0".468
6) seating and crimping in two separate ops.

I could go to 0.471"
 
Try this; pull the seating stem from the die. On a nice flat surface take ten bullets and one at a time place the seating stem atop the bullet and measure total length of each one. Then let us know if they all measure the same. Bet they are not.
 
Crimp should not make a difference,however case ID does.
The more uniform your cases are,the more consistent your results will be.Worn out cases tend to offer less resistance to seating if your cases are fairly new then you have to look at your setup.
 
I decided years ago that to get consistent seating depth/OAL readings I would use a flat stem punch in my seater for all handgun loading. works great since I cannot figure out how to have a seater stem for ever different bullet I have loaded.

Now that I am settling on flat point bullets it really makes no difference.
 
kmz1954........."Try this; pull the seating stem from the die. On a nice flat surface take ten bullets and one at a time place the seating stem atop the bullet and measure total length of each one. Then let us know if they all measure the same. Bet they are not'

Disassembled the seating and crimp dies to find a circular sliver of lead in the seating die and copper particles in both; aka FOD. Thoroughly cleaned both and my resulting OAL's are much better falling in the 1.260" window.

Lesson learned about cleaning!
now I can sleep

Thanks to all who responded.

P.S. one of the reasons I was so wrapped up with dimensions were concerns about future loading .40cal and 9mm. My understanding is that small errors in seating depth (like I was observing) can result in catastrophic chamber pressures.
 

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Terrific that you found the issue.

Actually what I was going to try and demonstrate is just how inconsistent the shape of the nose is on these plated bullets. Many times they will not contact the stem in the same spot which will change the placement of the finished seated bullet.

Think of it this way. With the ram raised completely and the die seated tightly the dimension between the 2 should always be consistent, shouldn't change as long as the press is not worn out. So if the bullets are exactly the same the length should never change.
 
"...0.468"..." If that's the diameter at the crimp it doesn't matter. Crimps don't get measured. The amount of crimp required is "enough to hold the bullet in place and no more". With 'enough' being the key word. Crimping is just like that.
"...a circular sliver of lead in the seating die..." That'll do it. Always look for the simplest fix first. Cleaning your dies is the simplest of anything.
 
My reloads ( 45 ACP Auto ) using the RCBS seating taper crimp die for the 230 gr RN FMJ using the round nose seating stem . When seating and crimping ( taper ) in one step my OAL wasn't as accurate , when seating then crimping in two steps my reloads were dead on accurate . Takes longer but stops any chambering problems . I'm still not getting every round perfect , I'll get a slight bulge on one side of the case every once an awhile .
 
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Make sure you have the right seating plug in the seating die. Usually comes w a round nose plug and a semi wad cutter plug
 
FWIW; lots of suggestions, but just eliminate/change one thing at a time. Crimping may or may not have much to do with OAL for semi-auto rounds, but something is wrong somewhere, so if you check several loads prior to 'crimping' this will show if the crimping process has anything to do with the problem. Same with other operations and/or dies or die parts. Good troubleshooting tactics eliminate/change one item at a time, step by step in a logical order.
 
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