Weight sorting brass.... ??

[lifesupport4u]

Sorting once fired Nosler 7mm Rem Mag brass and came across most of it is either 214 grains or 254 grains +/- 1 grain after all my prep.

Is this normal between maybe two lots to be 40 grains apart? Which brass should I use.... the heavier stuff?

 

[ShadowFast1]

That does seem like an extreme difference. How many do you have of each weight?

 

[VikingsGuy]

Dumb question, but did you leave spent primers in some?

 

[huntin24/7]

That seems like a lot for nosler. I love their brass. I measured all 50 rounds of a box of their 7 mag brass the other day. 47 were within 1/1000 of an inch. The others were within 2/1000. I was impressed.

 

[BWALKER77]

Two different mfgs.

 

[ImBillT]

Sorting once fired Nosler 7mm Rem Mag brass and came across most of it is either 214 grains or 254 grains +/- 1 grain after all my prep.

Is this normal between maybe two lots to be 40 grains apart? Which brass should I use.... the heavier stuff?

Yes it’s normal. Brass does vary considerably from lot to lot. Use them both. Keep them separated.

It’s not from two different manufacturers. Both came from Norma unless I’ve missed something somewhere.

 

[lifesupport4u]

That does seem like an extreme difference. How many do you have of each weight?

I prepped 50 rounds and have 19 at 254 grains, 26 at 214 grains and 5 outliers (216, 216, 216 and 236, 235). The 216s I will probably use. Not sure how close they need to be but was sorting to +/- 1 grain.

I have somewhere around 100 more cases to prep and sort now.

They are all from “Trophy Grade” 160 grain accubonds.

 

[lifesupport4u]

Dumb question, but did you leave spent primers in some?

Nope. All deprimed, wet tumbled, sized and prepped.

 

[lifesupport4u]

When I tested two different lots on the chrono of these factory loads there was a pretty significant change in FPS. I don’t have it documented any more. But it was a big reason I went to reloading.

Keep in mind these are once fired rounds from their Trophy Grade ammo. Not boxes of Nosler brass for reloading - which they say they weight sort each box.

 

[cahunter805]

I prepped 50 rounds and have 19 at 254 grains, 26 at 214 grains and 5 outliers (216, 216, 216 and 236, 235). The 216s I will probably use. Not sure how close they need to be but was sorting to +/- 1 grain.

I have somewhere around 100 more cases to prep and sort now.

They are all from “Trophy Grade” 160 grain accubonds.

Keep the 216 with the 214s. Sort the rest and keep everything separate. Whichever bunch has more cases I’d use that batch and sell off the other batch.

 

[VikingsGuy]

When I tested two different lots on the chrono of these factory loads there was a pretty significant change in FPS. I don’t have it documented any more. But it was a big reason I went to reloading.

Keep in mind these are once fired rounds from their Trophy Grade ammo. Not boxes of Nosler brass for reloading - which they say they weight sort each box.

Check the case volume of the two groups - I wonder how many grains of water difference there is in case capacity - this can have a significant difference in internal pressures and resulting fps (and safety margin).

 

[ShadowFast1]

Agreeing with VikingsGuy. Internal volume is the key thing when sorting. Weight sorting can get you close but there will definitely be variables that weight sorting doesn't account for. I weight sort but I'm not that good of a shooter that it would make a difference anyways.

 

[VikingsGuy]

Agreeing with VikingsGuy. Internal volume is the key thing when sorting. Weight sorting can get you close but there will definitely be variables that weight sorting doesn't account for. I weight sort but I'm not that good of a shooter that it would make a difference anyways.

I haven't weighed brass yet, as so far I have been developing hunting loads where 0.75 MOA is good enough. However, this summer I will be doing some 1000y shooting with heavier barreled rifles and will start splitting hairs and chasing 0.3 MOA. So, while I haven't been weighing brass I don't have a comparison point, but a nearly 20% difference in weight seems like a lot and assuming similar density of brass alloy common sense suggests there has to be significant different in case volume - and if you have ever played with Quickload differences in case volume can make pretty substantial changes in chamber pressure.

 

[ImBillT]

Within a “batch” that I keep together, I shoot for around +/- 1.5 to 2.0gr. Weight sorting is a proxy for volume. It is best done after uniforming primer pockets and length. If you’re turning necks, do that before sorting as well. Even a 5gr span(+/- 2.5gr) will not show enough difference over a chrono to be a big deal, especially once you factor in the actual SD/ES of the load, even if you test it with 10 pieces weighing the exact same amount. 216 vs 254 will not likely result in a safety issue if you’re following good reloading safety measures, (remember, load data was not produced with your brass, and most of it was not even produced with your brand of brass)but would give enough difference in velocity to show up on paper. Just sort it and don’t mix them. I have a feeling that you’ll have plenty in each group when you finish sorting it all. You’ll probably have some that land outside of +/- 2.5gr, and may even turn up another distinct batch between the two you currently have. For the ones more than +/- 2.5gr, if they clearly belong in on of the groups, just at the extreme end, I’d be surprised if you could consistently see the difference on paper. You really have to be sub .5MOA ALL THE TIME, for a lot of the little things to matter.

You could probably shoot two from the 216gr group and three from the 254gr group and still shoot 1MOA at 100-200yds.

 

[300stw]

i use to buy 500 rounds of brass at a time, go thru the prep process, full resize, trim to length , primer pockets in and out, lite outside neck turn, weight sort, and keep the batch in the middle within like 5 grains of each other, then sell the rest, anyway, during this time I started shooting a lot, like 200 rounds a weekend, 7mm rem mag, a gun that is consistent .6moa gun out to 800 yards, low on brass, I started using all of it when I was in a pinch, group size didn't change that I could tell, so I quit sorting,,,

 

[sbhooper]

I have never weighed brass, but just kept it consistent by manufacturer. I have never felt like I had an issue caused by this. I chase accurate hunting loads and don't split hairs, like br shooters etc. The pressure thing would definitely be more prevalent, if you are squeezing the max limits.

 

[BWALKER77]

Yes it’s normal. Brass does vary considerably from lot to lot. Use them both. Keep them separated.

It’s not from two different manufacturers. Both came from Norma unless I’ve missed something somewhere.

Nosler, has used a few manufacturers for their brass.

 

[ImBillT]

Nosler, has used a few manufacturers for their brass.

Well there ya go. May have been two manufacturers then. Although, I’ve had similar differences in different lots of Lapua .308Win brass.

 

[Brian in Montana]

I've never weight sorted brass. I load for hunting rifles and although I've heard of this practice, I've never really worried about it. I'm kind of meticulous about case length, but does the weight really make a noticeable difference?

 

[VikingsGuy]

I've never weight sorted brass. I load for hunting rifles and although I've heard of this practice, I've never really worried about it. I'm kind of meticulous about case length, but does the weight really make a noticeable difference?

Weight is a proxy for volume. >3% can cause velocity differences that show up more as range increases. Matters to to target guys and not hunters typically. My concern in this instance is the 20% variation. If that translated to a 20% increase in internal volume that would, I think, have pressure effects if one was loading near the top.