Bullet seating inconsistency?

Boomer454

Boomer454

CGN frequent flyer
Rating - 100%
107   0   0
Location
Southern Alberta
Working up a load for accuracy in my 223 so I loaded 3 sets of five rounds. Same powder charge and different OALs.

Why do some end up with a much different length if I haven't changed the die at all?

Using 69 grain smk's and I had four out of 5 seat at 2.280 and one at 2.255. It was the third one in the row so I know I didn't bump something.

Is thus bullet length inconsistency?

Using RCBS standard dies since I know someone will ask.
 
Bullets will vary in their dimension from ogive to tip. Have you measured from cartridge base to ogive (using something like a Hornady bullet comparator on a caliper)?

I suspect this is what you're experiencing, provided you checked the obvious like the tightness of the die in the press, no debris in the shellholder, etc...
 
Checked the die over and over. I also measure ten bullets from the box after my last post. They did vary by +/- five thou, but not the twenty thou I had with that one round.
 
I have a RCBS Rock Chucker, I've found that the amount of pressure that is applied to the handle at the end of the stroke (when the ram is all the way up) will make a bigger difference in seating depth variances than nose shape. This can occur even if the shell holder and die make contact... (in my experience)

SL
 
SavageLapua said:
I have a RCBS Rock Chucker, I've found that the amount of pressure that is applied to the handle at the end of the stroke (when the ram is all the way up) will make a bigger difference in seating depth variances than nose shape. This can occur even if the shell holder and die make contact... (in my experience)

SL
Click to expand...

This seems to be my observation as well.
 
I'm using a Lee turret press, and I try to be as consistent in the motion as possible. I've also gained the impression that the way I move the handle effects the seating depth consistency.
 
With the rock chucker, set the die so that it seats at a fully raised ram, and don't push hard once you hit the stop. This will make consistent seating. As far the press goes anyway
 
It could have to do with the part in your die that makes contact with the bullet , I have a crusher 2 press and when I used a Lyman regular die I would have variances , now I have a rcbs competition die set for .308 and it says that the seater is matched to the ogive of a 168smk And when a bullet comparator is used on my calliper it shows +/- 1 thou if I just read the tip coal it reads +/- 5thou
If the bullet being loaded is lead tip make sure the seater makes contact with the jacket and not the tip !
 
Funny, I'm having the same problem. I have a Lee Turret press also. I removed the auto-index and I could get 10 OAL's @ 2.815 and out of nowhere, I'd get one or two at 2.800. The projectiles are Match grade Hornady's and are almost exacly the same length( varies way less than the seating variation)Everything is spotless and I try to always apply the same amount of pressure. For now, I'm backing off the Die screw a whole turn and I simply seat them one by one and adjust for every bullet.
 
Not sure about turret presses but for my Lee press I seat then back the handle down give the case a quarter turn then raise the team again and repeat. I do it very quickly and by raising the cartridge in the seater three times at different points of rotation I get very consistent results. The Lee press I use does not cam over. Specifically I Haven't encountered your problem exactly, I just got inconsistent results from one to another. Could be bullet alignment before seating causes the bullet to be gripped on one side of the seating cone further down. Is the seating cone polished?
 
You must log in or register to reply here.
Back
Top Bottom