redding .288 neck bushing gives me .284/.285 plus flare

[rockwind1]

using redding t-7 press, for 6.5 creedmoor. using a redding full length bushing die with a .288 neck bushing, 1x fired norma (prime) brass, cleaned and deprimed. shoulder bump seems fine at .002 but i put the brass thru and the neck comes out .284/.285 ish,, plus the very tip of the neck is a slight bit flared at .286 ish.

the neck measure .2965-.2070 prior to sizing

i was running .002 of neck tension with a .290 bushing using expander ball, and the loaded round is .292. but i wanted to try a mandrell to help with roundness and concentricity, so i thought i will go down to .288 and then mandrell it out to .290,,,,,,but as stated above, it is definitely not coming out at .288

now i don't mind if it is a little bit off, like .287 or .289, but the flare at the tip seems weird and .284/5 seems way off. using mitutoyo calipers.

i mean, sure i can go back to doing it the old way but i want to know what is happening.

has anyone come across something like this before, is there a nail in my forehead? i don't understand!!!

 

[jepp2]

What is your fired case neck OD? There have been cases of what you describe (neck undersized with flare on top) but it is normally related to stepping down too much in a single sizing.

 

[243winxb]

Fired OD to sized OD should not be more then .008" difference. If 8 or more, the finished OD is smaller the marked bushing size. Read Reddings info on there website.

The mouth flare is strange. I only seen it when sizing a 308 fired case in a Redding 243w type S fl die. No bushing was in die at time of sizing. Over sizing?? My guess.

Spring back- Brass has a memory. Bushing outward. Expander inward.

 

[rwj]

Have you measured the bushing’s ID?

 

[nmkid]

Wow! never had that happen. The mandrel should take care of the flare.

 

[rockwind1]

Fired OD to sized OD should not be more then .008" difference. If 8 or more, the finished OD is smaller the marked bushing size. Read Reddings info on there website.

The mouth flare is strange. I only seen it when sizing a 308 fired case in a Redding 243w type S fl die. No bushing was in die at time of sizing. Over sizing?? My guess.

Spring back- Brass has a memory. Bushing outward. Expander inward.

that must be it, the neck measure .2965-.2070 prior to sizing, so i guess i am just over the limit,

i wonder if the mouth has more spring back than lower down on the neck.

 

[rockwind1]

Have you measured the bushing’s ID?

What is your fired case neck OD? There have been cases of what you describe (neck undersized with flare on top) but it is normally related to stepping down too much in a single sizing.

the neck measure .2965-.2970 prior to sizing


i guess i am sizing down just a bit too much. dang. nothing is ever simple in this biz is it.

 

[rockwind1]

i went up to a .290 and it is sizing down to .288 which is what i wanted, still a slight flare, after i mandrell them, the flare seems to go away. prob just shoot them and see.

 

[243winxb]

Fired is .297" ? The .2070 is a type O?

.2070 prior to sizing

i went up to a .290 and it is sizing down to .288 which is what i wanted, still a slight flare, after i mandrell them, the flare seems to go away. prob just shoot them and see.

At fired .297" and using a .290" bushing should work? The flare is still a mystery to me.

As long as the loaded round neck diameter is .295" or less, should be ok to fire.

 

[rockwind1]

Fired is .297" ? The .2070 is a type O?




At fired .297" and using a .290" bushing should work? The flare is still a mystery to me.

As long as the loaded round neck diameter is .295" or less, should be ok to fire.

Yes it was a typo thanks. I fixed it