Equipment Question

[Punisher29073]

My cartridge overall length is varying by a 2-3 hundredths. Is this normal or do I need a new press? I am working with a Lee Challenger. I am eyeing a rock chucker, but if this is normal, I will just by more bullets and powder.

any help is appreciated.

Ryan

 

[milo 2.0]

Your oal diff may be caused by your equipment, but I say it could be in the bullet itself. You never mentioned if you're measuring tip to base, or using a comparator. Bullet base to ogive can vary up to .006", and then there is Berger meplats. Unless you have a newly reamed chamber, and your throat has eroded some, I'd buy the components.

 

[Punisher29073]

I am measuring with dial calipers tip to base. SMKs and Barnes LRX bullets.

Ryan

 

[milo 2.0]

I am measuring with dial calipers tip to base. SMKs and Barnes LRX bullets.

Ryan

Measure a number of bullets the same way, see what you get. I seat with a Forster coax, Redding comp dies, if I get .002 either way, I'm happy, and it still shoots.

 

[scatterbrains]

tip to base will always vary try from "ojive" to base using a comparator

 

[Punisher29073]

Measure a number of bullets the same way, see what you get. I seat with a Forster coax, Redding comp dies, if I get .002 either way, I'm happy, and it still shoots.

That is a good idea. I will measure that tonight. I am using regular rcbs dies. I guess i was wondering if this type of variation is normal with regular dies vs micrometer dies. Or is likely the variation comes from my weak puny little baby press.

Ryan


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[milo 2.0]

Really Ryan,
It's normal with both types, people just won't let you know that. Poly tipped bullets out of a reg RCBS should almost be some of the most uniform you can get, IMHO.
It's when you measure ogive with a comparator things take a turn. The only thing I can suggest is having the press mounted stiff, and stroke each case the same. If there's not a bunch of neck tension when seating, and you get to ramming and jamming, the speed of your stroke can push bullets farther into the case than you want. Consistency is the key!

 

[No1]

2-3 hundreths? like this 0.020-0.030"? or 2-3 thousandths, like this 0.002-0.003"?
I would be concerned if it is hundreths but not thousandths.

 

[Punisher29073]

It is hundredths. Not thousandths.

Ryan

 

[Jig Stick]

Measure from the ogive. That's really the measurement you want. The only time I measure to the meplat is if I'm worried about the rounds fitting in a magazine.

 

[Mad_Charlie]

It is hundredths. Not thousandths.

Ryan

Now that's a scary thought, .002-.003 is nothing (base to tip) but .020-.030 is a LOT!!

 

[milo 2.0]

It is hundredths. Not thousandths.

Ryan

Holy shit, disregard anything I told you, you've got issues! We need to punt.

 

[Punisher29073]

There is up to .030 difference in the tip to base measurements. Is this likely in the press or die?

Ryan


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[peligro113]

measure from the ogive with Hornady comparator not the meplat because as you have seen you will have variances, I used a Challenger today to load some 69 and 168 smk's and the were all within .001-.002 of each other using the Hornady comparator. Is your load a compressed load? If it is you might be crushing the meplat.

 

[scudzuki]

Bullets contact the seater in a seating die on a contact ring between the meplat (tip) and ogive (area of the bullet where the diameter equals the lands diameter of the barrel) so depending upon uniformity of the bullets, even if the press repeats with a few ten thousandths of an inch (not that unlikely) the resulting ammo may vary quit a bit when measured at the ogive or the meplat.

Joe

 

[milo 2.0]

Bullets contact the seater in a seating die on a contact ring between the meplat (tip) and ogive (area of the bullet where the diameter equals the lands diameter of the barrel) so depending upon uniformity of the bullets, even if the press repeats with a few ten thousandths of an inch (not that unlikely) the resulting ammo may vary quit a bit when measured at the ogive or the meplat.

Joe

With a regular RCBS seating die, I'm not 100% sure that the plug is on the ogive. Ryan, are you getting a ring on the bullet from the seater plug?
I will say this, your equipment is not the best per say, but is good enough that this shouldn't happen. The issue is probably so simple that it's laughing at us. Are you running a compressed load with light neck tension?

 

[scudzuki]

With a regular RCBS seating die, I'm not 100% sure that the plug is on the ogive. Ryan, are you getting a ring on the bullet from the seater plug?
I will say this, your equipment is not the best per say, but is good enough that this shouldn't happen. The issue is probably so simple that it's laughing at us. Are you running a compressed load with light neck tension?

It's not possible for the plug to push the projectile in at the ogive; the bullet would ride into the plug, damaging the jacket and likely sticking in the plug when the ram is retracted.
If a custom plug were machined for every bullet profile, then the plug could contact the bullet over a greater area closer to the ogive with lower probability of wedging the bullet into the plug, and greater uniformity of length to the ogive would be achieved. The COAL would still vary with the actual profile of the bullet.

Joe

 

[milo 2.0]

It's not possible for the plug to push the projectile in at the ogive; the bullet would ride into the plug, damaging the jacket and likely sticking in the plug when the ram is retracted.
If a custom plug were machined for every bullet profile, then the plug could contact the bullet over a greater area closer to the ogive with lower probability of wedging the bullet into the plug, and greater uniformity of length to the ogive would be achieved. The COAL would still vary with the actual profile of the bullet.

Joe

Wow, I was just trying to make sure the bullet tip wasn't used in the seating process, and the ring would prove not. I've had many seaters put rings on the ogive, had to buy vld seater plugs for Redding dies. I don't know what you refer to as ogive, to me it's from the end of bearing surface to the tip. You seem to refer to it as it comes in contact with the lands, or first contact.
You help the kid out!

 

[scudzuki]

Wow, I was just trying to make sure the bullet tip wasn't used in the seating process, and the ring would prove not. I've had many seaters put rings on the ogive, had to buy vld seater plugs for Redding dies. I don't know what you refer to as ogive, to me it's from the end of bearing surface to the tip. You seem to refer to it as it comes in contact with the lands, or first contact.
You help the kid out!

If the plug was contacting at the bullet tip the OP would not be seeing a variation in COL.

Although the entire nose of the bullet is called the ogive, the part that you are trying to control (and the part you measure) when "seating bullets to the lands" is the part where the diameter is the same as the land diameter. In order to do that, the plug needs to contact the bullet as close to that land diameter as possible.

Standard seating plugs are shaped to accommodate a wide variety of bullet shapes and do the worst with VLD style bullets, which is why you had to get custom plugs to seat those.

Joe

 

[Fuzzball]

"There is up to .030 difference in the tip to base measurements. Is this likely in the press or die?"

Neither. That's a LOT of seating variation and no die could do it, nor any press unless it's made of rubber. I suspect you're seating too quickly to have a consistant pressure applied. Slow down and work on your own consistancy.

I have two of the very small Lee "C" presses and a 'Chucker and a precision dial indicator so I can easily test press deflection under load. I was surprised to find that my big green "rigid" iron press actually deflects almost 3 thou while FL sizing .30-06 but the supposed weaker little "C" cheep presses of aluminum alloy don't deflect enough to even measure under the same loading...so much for that bit of 'common knowledge' crap. And seating puts FAR less stress on any press than FL sizing!

The ogive IS the tapered part of a bullet, from shank to meplat/tip; ALL rifle seating plugs are intended to work off the ogive. I've been doing this a long time and no maker I know of has even attempted to make a seating plug that makes contact at the bore diameter Doing that would make the mouth of the plug so thin it would be fragile and contacting bullets at the point of bore diameter wouldn't be helpful anyway.

Anyone gettin a bullet cut from the mouth of a seater plug can chuck it in an electric drill and hold a bit of medium sand paper to it to radius the edge of the cup. If a VLD bullet is bottoming out in the cavity just run in a small drill bit to deepen it a tad; 1/8" diameter and depth has worked for me.

 

[Punisher29073]

Roger that Fuzzball. I will work on my consistency. I was going through the last batch rather quickly. I will slow down for the next batch.

Ryan

 

[arnie19]

Measure some of your bullets from the base to the tip and load some that measure the same length .Those should seat close to the same OAL., but an ogive measurement is the best way. Some anal shooters measure all there bullets and separate by the ogive to base length as they are different .

 

[Rprecision]

I seat bullets in three stages.

1. Start the bullet (about 1/4 the length of the bullet

2. Lower ram rotate case 1/4 - 1/3 turn seat the majority of bullet

3. Lower ram rotate case 1/4- 1/3 turn seat full cam over / ensure press reaches full stop

I started seating this way early on and its a quick habit. It helps generate concentric loads, spreads out misalignment and ensures consistent COAL.

Just another approach.................