Bullet Sorting

[Joe C]

Hello Everyone.

Found something interesting today as I was loading for the upcoming match. I'm shooting Sierra 107 SMK's and decided to sort them by ogive length and then weigh them. In the box I was using there were basically three lengths. The first is .660" then there are the ones that run .667 +/-.002" and then there are the ones that measure .655" +/- .002.

After I sorted by length I weighed them. The .660" weighed in at 106.9-107. The .667" weighed in at 107.1-107.3 and I didn't bother weighing the smaller ones as there were only a few. But, this was out of 200 bullets in a 500 round box.

I would be interested in hearing your thoughts on this and how it might effect accuracy at 600-1000 yards. As a side note I am shooting just the .660" bullets in the match.

 

[nfa1eab]

What do you mean by ogive length? I sort them based on bearing surface length with a Tubb BSC and have found that the weights will correlate to the bearing surface length, so I don't weigh them. Sorting by BSL also seems to group them well for pointing with a Whidden die. They will shoot very well when you do the work and make sure they are all brothers for each match.

Ed

 

[lrgoodger]

I had the same exact experience with a 500 box of 107s, only I had about five different, very distinct groups. I'm not sure what constitutes a 'lot' at the factory, but I'm betting the line was at least started and stopped between each of the groups. If they had put all 500 pieces in from the same run, there would have been almost no variance at all.

 

[nfa1eab]

LR,

I have had the same experience as you. I usually get 4 or 5 distinct groupings when I start measuring and sorting 107 Sierras. But then, they are not $40 per box as the other brands are. I am o.k. spending a little time measuring, sorting, and pointing as I know they are all consistent when I am finished. I have measured a lot of the other brands and found almost as much variation in the dimensions. Upon inquiry, I was told that I was unable to measure the bullets accurately. ........ Nuff said. The other brands do seem to be closed more tightly and consistently at the tip than the Sierras, which is why I point them up with the Whidden die.

Ed

 

[Martin52]

LR,
Upon inquiry, I was told that I was unable to measure the bullets accurately. ........ Nuff said.

Ed

This tool might assist you, there have been a few posts on the Forum about it's capabilities.

There's also a relevant article on www.riflemansjournal.com - if I get time I will look up and add the direct link later today.

http://greensrifles.com/New_Products.html

Martin

 

[Martin52]

Here's the link:

http://riflemansjournal.blogspot.com.au/2010/09/reloading-measuring-bullets.html

Bob's tool (BGC comparator) will measure "that" distance

Martin

 

[LRPV]

I sort with the Buhay tool from Mark King. It is a pain and takes time but I think it's worth it. I found quite a bit of variance with the 107 SMK and that was just a box of 100. Two different 500 count Berger 105 hybrids showed some variance but the one batch was only about .004" total spread. I sorted one box of 105 VLD hunting and they were about as bad as the Sierras. I sorted 100 105 Amax with the AMP jackets and they came out more consistent than any of the others I have tried to sort so go figure. It is those few rouge bullets in the box that I want to get out of the mix so they don't blow my group up for no reason.

 

[DennisH]

I sort them based on bearing surface length with a Tubb BSC and have found that the weights will correlate to the bearing surface length, so I don't weigh them. Sorting by BSL also seems to group them well for pointing with a Whidden die. They will shoot very well when you do the work and make sure they are all brothers for each match.

I agree with the above. My BRX loves 107's, but their a PITA to sort. I don't go more than .002. I took two boxes of 500 and sorted them by bearing surface. I have 6 bags of sorted bullets, all marked with their measurement.

Is it worth it, YES, IMO, also trim the meplats. I don't point my bullets.

Dennis

 

[Joe C]

Very good info from you fellas as usual. Thanks for all the help guys!

 

[fdshuster]

Joe: I saw the differences in ogive lengths several years ago, and that's why my match bullet of choice is the 105 Berger #22428. Nothing to sort or weigh, and they do outshoot the 107 SMK's.

I've always suggested that the bullets are being made on different machines with different dies, then funneled into the same box's of 500 at the end of the line, but several who have close connections to the manufacture of match bullets insist that no reputable manufacture would do that. But what other explanation is there for these unacceptable differences?

When I raise this question, the response is complete silence.

 

[FroggyOne2]

FD,

Your not the only one that has felt that way about the SIE pills!

 

[Erik Cortina]

Joe C, do yourself a favor and get away from the Sierra's. They are a PITA to deal with and make shoot. Sorting them will give you too many piles to deal with.

For high BC, go to the Berger 105 Hybrid, you will still need to sort them, but it will be easier.

For consistency, to with the 105 Lapua "L's", lower BC than the hybrids, but there is no need to sort bullets.

Hope to see you on the line soon.

 

[amamnn]

Sierra is truly mass produced. Berger is sorta mass and sorta custom. Bullets like those made by individuals one at a time are custom made. If you look at the equipment lists that accompany match results you will get an idea of which is the better bullet--weight--base to ogive-- bearing surface--whatever your particular crank..............all other things being equal

 

[KevinThomas]

Frank,

Don't think you'd ever asked me that one . . . but I can tell you. It comes down to someone ont paying attention at any of several different stages. There's a tremendous number of variables that can change the way a jacket forms, from different lead hardnesses in the core, to differences in the amount of lube on the jackets as they're fed into the press. Everytime some factor that can impact such variations, the batch is supposed to be checked. If there's a measureable or noticable difference, the lot is supposed to be ended, and a new one begun. There's a couple others that will cause the next lot number to begin, even if they can't detect any difference. What you're probably seing is the occasional change being made in any one of these things, that the operator thinks won't effect the product, so he continues to run it into the same barrel, no lot change. Small lots are problematic, and a real pain to deal with, so there's probably some institutional bias against changing to new lots as well, although that's strictly unofficial. There's also the possibility that lots can be mixed (inadvertantly or intentionally, in some instances) at the wash & polish process, or again during inspection and packaging.

Berger normally runs smaller lots to begin with, and seem to deal with this very effectively. Their Benchrest background is also (no doubt) a factor in their extra efforts in this regard.

As Erik mentioned, you might also want to check out our new Scenar L's as they become available. Awesomely uniform bullets, and am really anxious to try some this year for some new AR-10s we built up for Long Range Service Rifle competions. With a little luck, we'll be running these at Perry this year for the LR matches.

 

[Joe C]

Fellas,

O.k. I looked in my reloading drawers and found that I have 800 Berger 105g BT, 155 Berger 108g BT, 200 115g VLD and then a box of 100 95g.

Do you think the 105g BT will give me better consistency than the Sierra 107's (of which I have about 3000) or the Hornady 105 A-Max (of which I have about 5000)?

Also, a question for Frank and those of you talking about Lapua bullets. I have a source for the 105 Scenar item number LU4HL6045. Is that the bullet you were referring to earlier? Or if not, how do you think these would work?

And finally to FO2, if I switch to the Bergers in the .240NMC should I back down a pinch on the N150 and work back up or just substitute and go see what they do?

Thanks everyone! You are really helping me to learn through this thread.

 

[fdshuster]

Joe: Measure & weigh them for comparison. You already have the numbers for the SMK's, do the same with the 105 Bergers. The 105 Bergers (#24428) are giving me higher velocities (2820 avg. vs 2785 for the SMK), with the same powder charge, primer, bullet seating depth and Krieger 1-8 barrel that has a .236" bore.

If you decide you do not like the #24428, I'll be happy to buy them from you at your cost.

I've never tried the 105 Lapua Scenar's, but am tempted now.

I use the 107 SMK's for non-match's only.

 

[Joe C]

fdshuster,

The Bergers I have are the 24029 bullets in 105 weight. Not sure what the difference is between them and the 24428 but what I do know is I measured about 30 of them with the equipment I have here and they all were within .0005 of each other in length and they all were within .1 grain of each other in weight.

Now I have some 105 Scenars coming to me to try from a very nice forum friend. I think the Scenars and Bergers are going to allow me to tighten things up just a bit. I'll also give the Amax a fair shot as I've heard a number of guys say they shoot very well also.

The kindness and generosity of forum members here never ceases to amaze me. Thank you all and please, keep your thoughts coming!