shooting sorted bullets by weight question

[SDDasher]

Okay,
I have finally decided to break down and sort bullets/cases by weight and was wondering which do you shoot first, the heavier or lighter weight bullets or is that immaterial? (do you just shoot those that are + or - 1.5% in a twenty round group for an F class string?) Comments are welcomed on what works best for you....thanks

 

[TonyR]

I like to shoot the light ones first on the theory that the pressure builds as the gun heats up and the extra inertia helps offset the extra pressure. I also sort the cases descending by weight for the same reason. I have done some testing that suggests that the combined effect does help hold vertical in an F-Class string.

 

[nfa1eab]

Tony,
That's interesting. I used the same theory. Shot the heaviest cases first when the barrel was cool and the lighter ones as the barrel heat increased to maybe offset the extra pressure. With a standard 280 Remington, I would sort the cases to within .2 gr. for each match set. Bullets I quit weighing and sort by bearing surface length (which seems to correlate with weight). No variance in BSL for each match set. Don't really know if it helps, my wind reading is usually the weak link in my chain. But it does seem to reduce vertical.

Ed

 

[JERRYHM]

Do you really think it makes a difference? Shoot Berger bullets that DO NOT need sorting. In F-TR 308 the best bullet is the Berger 185 LR BT, for the 223 the best Bullet is the 90 BT or VLD.

 

[SDDasher]

Bullets maybe so....but cases do have a significant difference in weight from the ones I have measured from Lapua in both the 6BR and 6.5x.284. That is one of the reasons for wanting to sort to see if there is a measurable advantage to doing so......

 

[nfa1eab]

I have seen the comments on not needing to sort Berger bullets and petty much don't buy it. I've weighed and measured enough of their bullets to realize that they have variation in BSL and weight, and while they exhibit less variation than say Sierra's, it is there none the less. The physics behind why this variation does not effect their bullets has never been explained to my satisfaction. It is logical to believe that you should not have to sort custom bullets that cost $10 more per 100, but my results during measuring and weighing never gave me the warm and fuzzies on that one. Do I have statistically sound data to prove they need to be sorted? No, but I have also never seen data that proved that they don't benefit from sorting. In the end, many of the steps performed by long range shooters in the pursuit of precision down range probably are more significant from a confidence standpoint than they are from a measurable effect on target. I do the things that give me the confidence when turning the knobs that it was a condition change and not my ammo.

 

[Bob3700]

I have to say that my experience sorting bullets by BSL coorelates with nfa1eab. I stopped weighing bullets cause once sorted by BSL, they were the same. Sorting reduced the vertical dispersion significantly.

If I pull the Berger bullets out of the box and just shoot them, groups are larger. You can measure the yellow box bullets for BSL and they still have significant enough variation that affects their grouping ability at MR and LR distances.

There are no "Magic Bullets", I sort them all and see a difference on target.

Bob

 

[SDDasher]

Okay, so now the question becomes more does it make more difference to sort the bullets or cases (or both and if so; do you put the lighter (shorter BSL into the lighter weighted cases or vice versa) on vertical dispersion on target?

 

[Bob3700]

I will sort the bullets by BSL, then cases by weight. Only load bullets that have the same BSL. Don't mix and match bullets with cases. That is too many variables for my simple mind.

Now take loaded rounds and weigh them. Shoot the heaviest first and the lightest last. As the bbl heats up, the lighter loads will have more heat to contend with and develop higher pressures. Try it.

As German Salazar once told me, know what is chasing you!

Bob

 

[SDDasher]

Okay, thanks Bob. Now one last question (yeah right!) How do you measure the BSL? (please don't say with a set of calipers....ha!)

 

[Bob3700]

I have one of the Tubb Bearing Length checking tools.

Bob