Frustrated with my new .270 seating die!

Roughshod

Roughshod

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Just picked up a set of RCBS .270 Win dies today and all was going great until I got to seating the last 5 rounds. I measured the c.o.l. on the last few and found them to be .3 too long. Everything seemed tight but I adjusted the die and tightened it back up. Ran the round in again and when I brought it down it ripped the bullet clear of the case and stuck in the die. I got the bullet free, tried again and crushed the case. Next round seated but was high again, pressed it once more and it pulled the bullet free. Doesn't seem to be any junk in there. I'm stumped. Bullets are Barnes 130gr with a polymer tip. At first I thought the tip was creating the issue by hanging up somehow. Any thoughts?



 
0.300 or 0.030 or 0.003 to long? the seating stem should push on the ogive not the bullet tip. ULD bullet designs are a bit of a bugger with some seating stems, call RCBS on Monday and explain to them whats happening, in the meantime I know you want to carry on loading, so take a piece of fine sandpaper and cut it to lay over a bullet, then twist your seating stem over the bullet and sand it to match the bullet profile a bit better, it will stop the stem from cutting into the bullet or stretching over it and grabing the bullet rather then guiding it into the case.
 
The mouth of the seater plug has a sharp edge and is "biting" into the circumference of the bullet, try and polish the mouth of the seater and round its edge. If that doesn't work you will need to send two or three bullets and the seater plug back to RCBS and they will make a custom seater that contacts 100% of the bullet.
 
Sorry, the last few were .03 too long as though the stem stretched. I can't seem to get a clear enough picture of the last few bullets to show the scoring where the stem seems to be grabbing them. The first 35 rounds seated beautifully.
 
0.030 is huge...............I would think that the neck tension of your brass would hold the bullet enough that the stem couldn't pull it back out....


now then.........how did you set up the seater die?? are you trying to seat the bullet and crimp at the same time?? Is it possible that your seating die is set to low and hense causing you grief? Did you know that a Canadian nickel between your shell holder and die bottom will set the die up high enough that the crimp part of the die will not contact the case neck.......Did you also know that a hard crimp will cause neck tension on the case neck to get so tight that the bullet may either seat long and or crush the shoulders of the case........
 
Thanks for the nickle tip.

I set up like I normally do, I'm using a Rock Chucker. Insert the shell plate, extend the ram fully, screw in the die until it contacts the shell plate and then back out the die one and a half turns and visually check that the die is not contacting the ram/plate and adjust accordingly then tighting the lock ring. I do try to seat and crimp in one step.

The necks all seemed to have sized properly, feels like plenty of tension when trying to seat the bullets. The first thirty rounds seated without issue. The last ten rounds is where I noticed the seat was too high and felt the bullet "sticking" to the stem on the downstroke. The last five of the ten is when the stem pulled the bullet free and scored the bullets.
 
It could be that the bullet seating die is set too low in the press and you are actually contacting the case mouth with the die (crushing the case) at some point. This might explain why the bullets end their travel and seat long. Try turning the die out (raising it) and using the adjustable bullet seating plug to adjust for bullet depth. Polishing the seating plug is never a bad idea either.
 
Same thing happened to me.
Two problems
-the grooves on the TTSX reduce the amount of grip the neck has on the bullet.
-the bullet seater is not letting go of the bullet.

I tried :polishing the area where the seating plug contacts the bullet.
Or reduce the diameter of the expander plug to increase the neck tension .
I just swapped the seating plug from my .338 die to my .375.
 
Roughshod said:
Thanks for the nickle tip.

I set up like I normally do, I'm using a Rock Chucker. Insert the shell plate, extend the ram fully, screw in the die until it contacts the shell plate and then back out the die one and a half turns and visually check that the die is not contacting the ram/plate and adjust accordingly then tighting the lock ring. I do try to seat and crimp in one step.

The necks all seemed to have sized properly, feels like plenty of tension when trying to seat the bullets. The first thirty rounds seated without issue. The last ten rounds is where I noticed the seat was too high and felt the bullet "sticking" to the stem on the downstroke. The last five of the ten is when the stem pulled the bullet free and scored the bullets.
Click to expand...

try seating the bullet only with the die raised even farther in the press, then crimp in a separate operation with the seater stem removed.
the neck tension is to great while crimping and the seater plug is being pushed to hard against the bullet
 
This is an easy problem to fix.

It is best to make your seating stem conform to your particular bullet. This can be done by sacrificing a few bullets, and use them (with valve grinding compound) to reshape the contact surface on your seating stem. (A drill gun or drill press will work.) You never get scrape marks on your bullets again. Case concentricity is also better because the bullet gets started with a better alignment.

It's not a bad idea to have a second seating stem to fit other bullets - if needed.
 
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