Weighing Bullets

[280shooter]

Just got my GEM PRO 25 today after setting up an everything. I tried weighing a box of 6mm 70 gr bullets high 70.10 low was 69.90. Now my question is what weight spread should I sort these in ? Or is .20 small enough to just shoot.
Rifle is a 722 rem 244.
what do you think?

Thanks Johnnie

 

[Nomad47]

Not trying to be a wise a$$$, but why don't you shoot three with the highest ES of weight and shoot 3 of identical weight and see if it makes any difference.

 

[Terry]

.70 x 1% = .007

+/- .01 Shoot them, No point sorting.

Terry

 

[ar10ar15man]

sierra uses plus or minus .3....you are well inside that...i would shoot them as is.

 

[280shooter]

Thanks guys just was wanting some imput they were sierra 70 gr blitzking's

again thanks Johnnie

 

[mac86951]

Not trying to be a wise a$$$, but why don't you shoot three with the highest ES of weight and shoot 3 of identical weight and see if it makes any difference.

Always a good answer. Try an experiment and see. 0.1gr in my .223 make a difference, but not so in my .30-06. YMMV

-Mac

 

[searcher]

I would first do a mental check of what your rifle is capable of based upon the best groups you have been able to obtain with your best loads. I would not expect to see a big difference if your rig shoots 1" M.O.A. If it is a real tackdriver and shooting long distances where 1" difference at 600 yards means the dfifference bewtween a hit and a miss - I'd be inclined to weigh to a tenth grain or less, depending on how many bullets you have. If shooting live critters such as squirrels, it makes little sense to have you bullets sorted into 15 weights unless you have enough in each group to test fire for scope adjustments, etc. If target shooting at known repetive distances, many batches are O.K. Going from one weight to another in the middle of a match merely means another sighter or two beforehand. If nothing else, you have "peace of mind" in knowing a flier wasn't solely attributed by bullet weight variation alone.

 

[280shooter]

Thanks guys

 

[lpreddick]

my ocd/anal personality makes me not only weigh bullets, but measure base to ogive. the latter can drive you crazy! once had a box of 87 gr (brand name omitted) bullets, none of which weighed 87 gr and could only find 8-10 with the same base to ogive measurement! called manufacturer and they sent a new box. SAME LOT as irregular ones! but, weighed and measured and lo and behold, they were all identical! i will on occasion find base to ogive bullets that meas into two groups, being as much as .010 different. variations in the length of a bullet bothers me more than a small dif in weight. custom bullets vary the least and some are no more expensive than mass produced ones.

 

[KevinThomas]

lpreddick,

That's an operator not following policy, and mixing bullets which should have become two different lots. Possibly a change of jacket material, maybe a change in the form die or a major adjustment, something like that. But that should have been the end of whatever was in the collection bin for that lot, and a new bin (and a new lot) started after the change was made. No reason for one box to be good and another of the same lot to be bad, unless someone just isn't getting with the program.

 

[mac86951]

lpreddick,

That's an operator not following policy, and mixing bullets which should have become two different lots. Possibly a change of jacket material, maybe a change in the form die or a major adjustment, something like that. But that should have been the end of whatever was in the collection bin for that lot, and a new bin (and a new lot) started after the change was made. No reason for one box to be good and another of the same lot to be bad, unless someone just isn't getting with the program.

Being a process engineer. I can understand both sides of the story. More reason, however, to check your incoming quality.

-Mac

 

[RCurtis]

I have always said that the only reason to weigh bullets is to cull the few weird ones. After that you can throw all the rest back in a box, load em up and go shoot X's

Rick Curtis

 

[Steve Blair]

I have always said that the only reason to weigh bullets is to cull the few weird ones. After that you can throw all the rest back in a box, load em up and go shoot X's

Rick Curtis

I'm always curious about this...what is the cut off for a "weird one" is it relative to that specific lot or specific to the weight tolerance the load was worked up on?

For instance +- .01 for one lot and +- .02 for another lot, is the second lot judged relative to the first lot and therefore there is a lot of culls from the second lot...or is it that you are looking for those real odd balls where its say .5 or more?

[br]
I agree with Rick but also sort using Bob Green's tool to obtain more accurate seating depth. [br]
If you model your loads in QuickLOAD, changing bullet weight makes some difference in muzzle velocity. In 6BR shooting 105 Hybrids, one grain makes about seven fps difference. In .284 shooting 180 Hybrids, one grain makes about four fps difference. Roughly speaking, for the cartridges I've examined, .5% bullet weight difference translates to ~.1% velocity difference. This is in long barrels, 30" and 32", respectively. Powders used were H4895 and H4831 SC, respectively. [br]
As Rick noted, it is worth culling the outliers. If you find wide weight variation, and I don't with Berger bullets, it may be worth sorting into groups for long range shooting.

 

[Nomad47]

Steve, I hope you meant one kernal makes a difference of 4 fps and not one grain of powder.

 

[Steve Blair]

No, one grain of bullet weight. The OP asked about weighing bullets. My examples assumed constant charge weight.

 

[Nomad47]

Thanks for the clarification - for some reason I was thinking grains of powder even though I knew the OP was asking about bullet weight.