Seating die issues

[wildfowler.250]

Sounds like you might have a fairly tight chamber/throat. Your factory rounds have been OK, I presume.

Yes and my friends factory ammo loaded no problem as well. These trial bullets did go in nicely so optamistic. Throat could be quite tight as you say though. Will post some updates on Friday - finger so crossed the weather improves!

 

[JTO]

Yes it’s been invaluable

I know exactly what you mean!!!

 

[paul o']

Glad your sorted mty hope you fall on a load first time

 

[DCG]

If you think you’ve got a tight chamber, be aware that PPU brass is often reported as having thick and inconsistent neck wall thickness.
If you find a brand of brass that works, it’ll be worth sticking with it.

 

[kenbro]

I think you’ve had the seating die screwed down too far, which has caused it to crimp on the bullet and also then push the whole neck down to damage the shoulder area.
Also, that balistic tip looks to be flattened over. Have you checked that the tip is not bottoming in the seater stem.
I can see a ring where the stem is contacting at/near the ogive, but, is the plastic tip deformed before the stem contacts the bullet jacket?
Regards,Ken.

 

[Grandhubert]

I thought I’d make this a slightly separate post to my last thread as it’s a more specific issue. So far I’ve done all the case prep and I’m trialing seating bullets in resized cases,(no powder) to get the correct length.

Im using new brass and full length resized them. Made sure they’re all similar length ect.

Im using accubonds in the .270 and nosler textbook says tested length 3.320”. Saami max overall cartridge length 3.340”.

Now my friend has previously given me nosler ballistic tips and they measure 3.250”,(textbook also tested these at 3.320”).

I sat the accubond a little ‘shallower’/less deep than 3.250 and worked back. When I got past 3.270” the bullet started getting stuck in the die,(now removed) twice.


I’d have thought this was less likely to happen when making the overall cartridge length longer? And can I set it to the shorter 3.250” and just monitor for signs of pressure?


The case neck subsequently also looks deformed and I’ve scrapped it. Anyone have any pointers as to why this is happening?


Stopped for the evening so I can look into this a bit further.


cheers!

You've got the die adjusted down so that it contacts the shell-holder at the top of the stroke of the press, which would be correct for a "dead length seating die" like the one that Lee makes.

The RCBS die has a taper crimp function built into the uppermost portion of the case neck portion of the die which is brought into contact with the case mouth (in which the bullet to be crimped is located) by virtue of screwing the die down towards to the shellholder with the ram fully raised.

These are in the instructions for RCBS dies, which I didn't read the first time either!

https://media.midwayusa.com/productdocuments/instructions/101/rcbs_reloading_die%20instructions.pdf

Note the bit about "screw in the die it just contacts a trimmed, primed and charged case and back it out 1/8 turn more" on page six, that keeps the crimping portion of the die from making contact with your case.

the photo you posted shows this very heavy taper crimp and because any further pressure is in the downward direction will cause the neck and shoulders to collapse rather than sizing the neck and bullet any more.

 

[ChesterP]

It does look like the seating die may be set too far into the press.

 

[wildfowler.250]

Cheers for all the help! Theyre chambering nicely so fingers crossed it's not blowing a gale tomorrow and i'll get to test a few. Starting initially with 4 rounds of 51, 52, 53, 54 grains powder. 55 was the max viht n160 and i've woosed out of it so far. Maybe work up to it if the initial loads don't group.


Will post a wee update. Cheers!

 

[wildfowler.250]

I know exactly what you mean!!!