ok guys,
I have a bullet comparitor when reloading my ammo that measures from the ogive. i use RCBS full length resizers. resize, prime, load powder then seat my bullets, but when i measure after loading the round using bullet comparitor, i am getting differences up to .10, what is the problem, has to be the die right?
btw, this is on a 300 win mag and 30/06 getting same results.

What bullet and what seating die?

Wrong seating plug for your bullet design.

rcbs FL die set, using barnes tsx 180 gr boat tail, and seirra 165 gr spitzer.
do these bullets require a diff seater plug?

on the sierra gameking bullets 165 gr measureing distance from the lands, 4/4 times i get 3.897 subtract the 1 inch zero and its actually 2.897

on the Barnes TSX i get 3.907 minus the inch zero and its actually 2.907.

so if i understand correctly, using the bullet comparitor, i should set my dies to seat the bullet to 2.902 to be 5 thousanths off the lands correct?

but when i do this, still measureing with the bullet comparitor i make sure everything is tight and right, every one of them are different. This is driving me nuts, i dont know why i dont understand this. Am i being too critical? Some are off by 7 thousanths, and its in either direction, Everything is absolutely tight i have checked and double checked.

2.902 puts you .005" into the lands. If you're looking for .005" off the lands you need an OAL of 2.892".

ok, sorry for the confusion, i posted my measurement using the barnes measurement, but you are correct on the sierra measurements, so any idea why when i set my press they would be different when using the bullet comparitor?

Wtman, in your initial post, you state:

quote:

Originally posted by wtman:
i am getting differences up to .10

In a later post you state:

quote:

Some are off by 7 thousanths, and its in either direction

So what is it?? Are you seeing differences in OACL (measured with a bullet comparator off the ogive of the bullet) of +/-.007" or are you seing differences of up to .100"???

+/-.007 is not totally out of the question, in particular with Barnes bullets. Because I don't want to have to deal with bullets sticking in my bore after unloading an unfired round, I always try to stay off the lands. Even with (factory) match bullets such as Sierry Match Kings, that means I normally stay off the lands at least .005" - simply because I have found bullets vary maybe .002-.003", even when measured off the ogive. Barnes bullets are notorious for varying quite a bit more than that - and I would not consider +/-.007" to be out of the question, although I have to admit never having measured TSX bullets. Normally, I seat these bullets far off the lands anyway (Barnes recommends .05"), so a bit more or a bit less does not seem much of an issue. TSX have shot well in almost all rifles I have tried them in - not match accuracy, but good solid hunting accuracy.

- mike

quote:

Originally posted by wtman:
so any idea why when i set my press they would be different when using the bullet comparitor?

Both the bullet comparator and the bullet seating die contact a certain point on the bullet curve or ogive. A measurement from that point on the ogive to the point where the bullet reaches full diameter is different unless the bullets have the same amount of secant ogive, so the measurements will be different. If you had a comparator or seating die that contacted the bullet at the point where full diameter is first reached, which is the same point on the bullet that first contacts the lands, then the measurements would be the same.

BTW, if you are not seating the TSX at least .03" off the lands then you are probably not getting the best accuracy. Some of these bullets get better past .05" in some rifles.

JMHO

MHO,
What i am saying is what i want to do with the barnes is set them .005 off the lands. So i make one bullet to seat at .005 off the lands, when i put the next bullet in the die and press it in, they very. A few of them will be, well lets just say they wont even chamber, others will be more like .012 off the lands. Was wondering if i have a bad die or what could be causing this. I was under the assumption that when measureing from the ogive that they would all be the same but you Woods have cleared that up for me by saying that they will still be different although mine seem to be off by more than +/- .002 . Now i should state that some are the same and some are not. Didn't mean to cause confusion,Heck, i am confused i fired some of them yesterday and they seemed at a 100 yards i could cover them with a nickel but the wind was around 10 mph but gave me a clover leaf pattern i could cover with a nickel. I think a little playing with the powder could tighten them up a bit more but for elk hunting i would say they are about good enough?

quote:

Originally posted by wtman:
MHO,
What i am saying is what i want to do with the barnes is set them .005 off the lands. So i make one bullet to seat at .005 off the lands, when i put the next bullet in the die and press it in, they very. A few of them will be, well lets just say they wont even chamber, others will be more like .012 off the lands.

If you are loading TSX, you are too close to the lands with .005". Barnes recommends somewhere between .030 and .070" - with .050 often being a good compromise. The TSX will vary more in the ogive than other bullets, and if you are too close to the lands, you may end up being in the lands for some cartridges and off the lands for others. You seem to be getting great results accuracy wise with your current setting, but some rounds are hard to chamber (possibly because bullets are long enough to end up in the lands). Seat your bullets deeper (start with .05" off the lands), your problem will go away, and your accuracy will likely be just as good (or better).
- mike