6.5mm 125 gr Partitions actual weight

martinbns · Nov 17, 2004

I don't know whether this means anything or not, but I used a 125 gr Partition to check my scale today and about 10 of them taken at random from my box all weighed 124.6 grains. For reference I checked several Barnes bullets and hornady's to make sure the scale wasn't off.
May mean nothing but I wonder why they wouldn;'t weigh 125 grains exactly.

NOSLER · Nov 17, 2004

We run a tolerance of +/- .2 of a grain. So the bullets would weigh 124.8-125.2

It would be better to calibrate your scale with weights rather than bullets. Most bullet companies will run their tolerances +/- .5 grain.

Eagleye · Nov 20, 2004

Good Grief!! Even top-notch target bullets for competition vary + - .1 grain, so I would be less than concerned about that much weight variance in a bullet solely designed for hunting. In fact, 1.0 grain variance will be undetectable on targets out to 500+ yards. In all fairness, bullets have become more consistent in the past decade or so, but to expect dead on weight for every bullet is asking too much. I never even bother to weigh any hunting bullet, since I firmly believe it is a non-issue. If you are shooting targets at 1000 yards, That is a bit different. Regards, Eagleye.

martinbns · Nov 21, 2004

I wasn't very concerned about it and the bullets were in fact extremely consistent, they were all 124.6 gr. I just wondered if it was intentional.

Jaywalker · Nov 21, 2004

I'm not entirely certain that a grain difference is undetectable. I agree the weight itself is relatively meaningless, but if the OAL of the bullet is constant, the weight sometimes manifests itself as a difference in ogive placement, and that makes a difference in distance to lands.

I went through a box of 100 Speer Hot Cor's in .264 140g and measured each of them with a Stoney Point Bullet Comparator. IIRC, the ogive lengths varied from 0.729" to 0.743," a pretty significant variance when 0.005" differences in jump to lands causes noticiable difference in group size. They varied one grain, high to low. They grouped poorly, until sorted by ogive length.

Hornady 140g SP Interlock max variance was 0.006," though I didn't weigh them.

I believe the Nosler 140g were only 0.001" to 0.002" variances, but I stopped measuring them, due to the small differences.

Jaywalker

FOTIS · Dec 16, 2004

Never really had them deviate that much from their claimed 125 gr. I use them exclusively in my 264 Win Mag.

cold_hunter · May 29, 2009

i have found that even matchkings very at least that much and more most of the time but as long as the jacket length of the bullet is the same all is well. BTs most of the time are alot closer in wieght i think this is because of them not having a lead point to get damaged.

Powerstroke · May 30, 2009

Wow.....
That's actually fairly impressive..... very consistent all 10 weighing the same..... a slight variance in the bullet, a slight variance in the scale.

Ol` Joe · May 30, 2009

Jaywalker":1anrgnwn said:
I'm not entirely certain that a grain difference is undetectable. I agree the weight itself is relatively meaningless, but if the OAL of the bullet is constant, the weight sometimes manifests itself as a difference in ogive placement, and that makes a difference in distance to lands.

I went through a box of 100 Speer Hot Cor's in .264 140g and measured each of them with a Stoney Point Bullet Comparator. IIRC, the ogive lengths varied from 0.729" to 0.743," a pretty significant variance when 0.005" differences in jump to lands causes noticiable difference in group size. They varied one grain, high to low. They grouped poorly, until sorted by ogive length.

Hornady 140g SP Interlock max variance was 0.006," though I didn't weigh them.

I believe the Nosler 140g were only 0.001" to 0.002" variances, but I stopped measuring them, due to the small differences.

Jaywalker

Actually as the seater acts on the ogive they should not vary in "jump", but will be seated to a slight difference in base depth. This will affect pressures but probably not enought to cause them to vary more then the "normal" pressure spread of the load.
Unless you are shooting 1000 yd benchrest I doubt it notably matters.