what is going on here? new 223 lapua brass, redding .248 bushing to neck followed by neck expander, load and seat bullets with redding competition die. resistence to bullet seating snug and consistent for multiple cases, THEN, a loose neck and bullet slips in with little resistence. measure bullet seating with comperator and this bullet is 5 to 10 thou deeper than the snug fitting ones. no adjustments were made to anything. bullets were measured base to ogive and were the same. necks were chamfered after sizing. expander felt same in all necks or was there a little difference? can't measure neck wall thickness. even if some necks are thinner, why would the bullet seat so much deeper? i am very gentle lowering the handle of the press. i cleaned the die completely but same problem...only when the bullet seats easily! the neck tension is obviously less with these rounds, so they have to be culled from load testing with the snug ones. if my memory serves me well, this event is more common with new brass. what is happening here? thanks loads(pun intended). [/quote] if i can see you, i can touch you. BANG!
bullet seating problem
- Thread starter lpreddick
- Start date
Beg, borrow or steal ( just kidding) a tubing mic or use some other reliable method to measure the brass neck wall thickness(s). I'm also using Lapua 223 Rem. brass and have never had that problem. I have had it though when using Remington, Winchester and Lake City for my AR's. Anytime I get a bullet seating with noticably less resistance, I look at the headstamp and it's always Remington, measure the neck walls, and it's always thinner. It's happened so often I no longer use Remington brass. Really unusual for that with Lapua, one of the reasons I use it exclusevely in my bolt guns, "other" brass for the AR's.
if i can see you, i can touch you. BANG!lpreddick said:
[/quote]
Looks like you are just neck sizing after firing and then running the brass through a K&M expander mandrel?? Sounds like your neck tension is almost at zero. Now if you get a case that is slightly less thick than the others (.0005) or less, you will get a bullet with no neck tension.
If i were you, i would get a full length die and take out the expander ball. Size the entire neck and bump the shoulder back .0015 or so. Then run them through your expander mandrel..... then size the necks using your bushing neck die of your choosing. This will let you achieve a more consistant neck tension.
Derek
lpreddick said:
WHY are you undoing what you tried to accomplish with the bushing by running that darn neck expander through the neck?
That's a complete dichotomy. Get rid of that expander. Throw it in the trash can! You'll never find one on a custom made full length sizing die with bushing capability.
What ever neck tension you imparted to the brass with the .248 bushing squeezing down on the neck you turned right around and either reduced it or completely eliminated it by following it up with expansion [the neck expander button attached to the decapping rod]. Remove the expander button and then see what happens.
Am I missing something here or what?
I think there are TWO problems here. The case problems were very adequatly treated above.
But, the fact that the loose bullet yielded a cartridge 5-10 thou shorter sounds to me like a seater problem.
I happily used a precision seating die and noticed the pressure I imparted on the press handle would modulate the seating depth. So, I started using a torque wrench to make each sest identicle. Then My friend noticed the same thing with the same brand seater die. The spring in the die was coil binding prior to the inner sleeve being depressed to the barrel edge. The manufacturer supplied a new, correct spring and no more different seating depths! Even though I screwed up on some cases and had really variable tension, the cartridge length varied less than a half thou.
I think there are TWO problems here. The case problems were very adequatly treated above.
But, the fact that the loose bullet yielded a cartridge 5-10 thou shorter sounds to me like a seater problem.
I happily used a precision seating die and noticed the pressure I imparted on the press handle would modulate the seating depth. So, I started using a torque wrench to make each sest identicle. Then My friend noticed the same thing with the same brand seater die. The spring in the die was coil binding prior to the inner sleeve being depressed to the barrel edge. The manufacturer supplied a new, correct spring and no more different seating depths! Even though I screwed up on some cases and had really variable tension, the cartridge length varied less than a half thou.
if the nk. walls are exactly the same thickness &tension is same you either have spring problems in seater or some of your bullets are smaller i ran into this exact thing with a bad lot or 155 gr.vld 30cal bergers a few yrs. back the jackets were thinner on some berger cheerfilly replaced them might want to check this thanks alan.
why didn't i think of that! normmatzen and shooter 63 probably nailed it.... THE SPRING in the redding seater die. the tighter neck resist the springs tension, while the loose neck allows the spring to recoil , uncoil, more completly, thus seating the bullet a few more thous of an inch. i cant't believe i didn't consider this element. spring tension and it's uncoiling will also explain why on occasion a bullet fails to seat by 2 or 3 thous only to do so by lowering the press handle slightly forcefully. i have done this a thousand times and never realized what was happening. man, do i feel dumb. open your eyes, think and see! does frequent shooting cause brain damage or is it my birth certificate? thanks everybody.[/quote] if i can see you, i can touch you.BANG!
Hey! Don't feel bad, I used my precision seating die for a couple years before finally questioned the results I got!
Then, at the proding of my mentor in Australia, I took a good look at the way the die was constructed and found the spring should have no say in the depth of seating. The inner sleeve of the die must collapse to the outer sleeve. With the original spring, it coil bound before the inner sleeve got to the outer die and the amount of pressure from the press could modulate the seating depth. First, we ground the end coils of the spring till the inner sleeve would depress into the outer cylinder. NO PROBLEM! Then the manufacturer sent us both new springs that were shorter so no coil binding, and not as stiff. Now, I find virtually no variation in seating depth AND I can feel the seating force needed as well.
We live and learn!
Then, at the proding of my mentor in Australia, I took a good look at the way the die was constructed and found the spring should have no say in the depth of seating. The inner sleeve of the die must collapse to the outer sleeve. With the original spring, it coil bound before the inner sleeve got to the outer die and the amount of pressure from the press could modulate the seating depth. First, we ground the end coils of the spring till the inner sleeve would depress into the outer cylinder. NO PROBLEM! Then the manufacturer sent us both new springs that were shorter so no coil binding, and not as stiff. Now, I find virtually no variation in seating depth AND I can feel the seating force needed as well.
We live and learn!
Upgrades & Donations
This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.