how much variance when seating ?

[black_ump]

well since i have my bullet comparator and my forster mic seating die i have went to town today and loaded a whole 5 rounds, but i seated some that i already loaded.

i want my oal to be 2.8 since i shoot out off a g3 platform (msg-90) i just though sticking to 2.8 would be best since seating to the lands would mean jams in the magazines.

so now that i use the comparator and measuring off the o-give the calipers should read 2.1835 and my question is will 2.1840 be ok ? how much variance up or down before their is a major difference 5 or 10 thousands ? or would even .001 make a difference ?


on a side note i notice my forster leaving a seating mark around the ogive its a ring that goes all the way around the ogive is this a bad thing ?

 

[Badshot308]

Re: how much variance when seating ?

It's Christmas eve, go to bed or Santa won't bring you anything...

 

[gcoulsey]

Re: how much variance when seating ?

Happy Christmas everybody

As much as 5-10 thousands may make a slight difference, it all depends on how forgiving your recipe load is in your rifle..

Less than 5, I wouldn't sweat it, as your not loading on the lands,
I typically get +/- .001 with my redding comp seater,

And as for the ring mark.. Try lightly polishing the seater stem,
As long as the ring mark isn't so bad that you can snag it with your fingernail, it shouldn't be a big deal.

 

[SScott]

Re: how much variance when seating ?

Do some load development, with rounds seated 5 thou apart,(within mag specs) keeping track with your comparator. Shoot them at 300-400 yards the winner will show its head at those ranges.
I worked up some 155 Lapua's yesterday and they liked a compressed load, and I went into the day thinking they would work best at longer lengths, I was wrong.
Oh and the ring from seating, my 68 grn .223's have one because they are highly compressed. They still are very accurate. As long as the ring is the same all the way around I consider it similar to a cannalure groove.
Happy Shooting.
SScott

 

[yotedog65284]

Re: how much variance when seating ?

sometimes the ring is caused by to much neck tension. Also use a VLD deburr tool and they will seat a little easier. The seating depth may be the neck on your brass getting a little hard, may need to anneil them.
good luck, Chris

 

[black_ump]

Re: how much variance when seating ?

ya the ring is weird... its up at the start of the ogive i tried to pick it with my finger nail and its smooth just annoying looks like a halo lol ill shoot these rounds and to load testing... iam not that worried about the ring just curious thats all.

well if your out their badshot i got my loads all worked up and as soon as i get glass iam going to show you what kind of a shooter i built hahaha

 

[jeremybowlin]

Re: how much variance when seating ?

I agree the ring is from to much neck tension. Anneal the brass and you will see a heck of a difference in seating pressure. When you seat the bullet do they all feel like it takes the same amount of pressure to seat the bullet?

 

[black_ump]

Re: how much variance when seating ?

yes they all feel the same

 

[Swan]

Re: how much variance when seating ?

Doubt it's the neck tension. The ring you see is probably from the seater stem marring the bullet ever so slightly. Get some emery cloth, chuck the stem up in a drill and lightly buff the inside of the stem. Ring will go bye bye.

 

[black_ump]

Re: how much variance when seating ?

i think i have something that might work, but would any of you mess with it or just let it be ? not like the ring is hurting any thing right

 

[Badshot308]

Re: how much variance when seating ?

I've used the Forester seating dies with 300 Win Mag, 308 Win and 338 Lapua Mag. All the dies left a very faint mark on the bullet. It's not a problem at all. However, if you have a particular type of bullet that is getting damaged by the seating stem, Forester will specially machine a bullet channel for that specific bullet, "CUSTOM J-30 SEATING STEM to fit specific bullet ogive's shape.
You should supply 2-3 sample bullets. (all customer property will be returned)
Specify for use with the Ultra Micrometer Seating Die or the Bench Rest Seating Die.
Retail price of J-30 Stem + $7 machining Fee + shipping. (Or, you may send in your existing stem & just pay the machining fee)" http://www.forsterproducts.com/store.asp?pid=30223&catid=19938