Brass, is it all the same?

[BECKS7]

Here goes,

I was thinking,is all brass created equal?
I have about a dozen boxes of federal blue box brass that I haven't touched because I have match brass to use. But after you clean size primp and prep all your brass, and if its all done the same, would you end up with all "match" brass" after it is all said and done, or weould the match brass still preform better?

 

[Wil]

Re: Brass, is it all the same?

different manufacturers will have different case capacities...

Lapua, LC, BHA, Win, Rem, FC, etc... they are all different internally. Some are thicker than others causing the internal case capacity to decrease.

Best way to test this is with a water capacity test.

Lapua, LC, and FC have less capacity than Rem, BHA, or Winchester...


DO NOT SWAP LOADS BETWEEN DIFFERENT BRASS !! REWORK THE LOAD IF YOU ARE GOING TO SWITCH PLEASE !!

 

[goober]

Re: Brass, is it all the same?

Some brass is way better than other brass especially lapua.consistancy in wall thickness in the neck area and also the case weight and how much pressure the case can take before the head expands and primer pockets go so loose you burn your bolt face with escaping gasses after no more than a few firings.I shoot 260 and was using remington brass but wont again due to how inconsistant I found the weight and durability to be of this brass.My extreme spread with rem brass and WINCHESTER was wildly varying compared to lapua brass -once weighed this would change a bit I am sure but still have noted the lapua brass keeps giving better results.

 

[Greg Langelius *]

Re: Brass, is it all the same?

No. Metallic composition and heat treat varies. This affects things like primer pocket expansion and neck area work hardening. Other factors may also vary, like dimensional consistency.

 

[Brent Thornton]

Re: Brass, is it all the same?

It's all been mentioned. Brass thickness and capacity is different between manaufacturers. I was initially taught to keep it all the same, and not mix your brass, etc.

 

[ChadTRG42]

Re: Brass, is it all the same?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Wil</div><div class="ubbcode-body">different manufacturers will have different case capacities...

Lapua, LC, BHA, Win, Rem, FC, etc... they are all different internally. Some are thicker than others causing the internal case capacity to decrease.

Best way to test this is with a water capacity test.

Lapua, LC, and FC have less capacity than Rem, BHA, or Winchester...


DO NOT SWAP LOADS BETWEEN DIFFERENT BRASS !! REWORK THE LOAD IF YOU ARE GOING TO SWITCH PLEASE !! </div></div>
Big +1 here. Plus, mfg often have different neck thicknesses which cause different neck tension on the bullet.
Pick 1 mfg of brass and run with it for accurate loads. You can use the mixed brass, but do not use a near max load. They are good plinking rounds.

 

[BECKS7]

Re: Brass, is it all the same?

Now if you prep your brass and just do everything you can to it, can you get say federal blue box brass to be as good as federal match brass?
I mean its all FC brass, right?

 

[ChadTRG42]

Re: Brass, is it all the same?

I would think it would be all the same if it has the FC stamp. Weight the case to the others and measure the neck thickness (and neck tension amounts) and see.

 

[mattmcg]

Re: Brass, is it all the same?

One trick I use quite often is measuring the true case capacity for a new lot of brass. Here is how to do it.

1. Measure the case weight dry
2. Measure the case weight wet with a concave water line
3. Measure the case weight wet with a convex water line
4. Add the concave measurement to the convex measurement and divide by 2 (gives you total capacity accurately with water surface tension).
5. Subtract the dry case weight from the wet case weight to find your case capacity.

Hope that helps.

 

[mattmcg]

Re: Brass, is it all the same?

Oh, and make sure to plug the primer hole with a non-stick wax or clay to contain your water! I can't tell you how many times I forget that step! ;>

 

[Greg Langelius *]

Re: Brass, is it all the same?

My brass prep consists of F/L resize and flash hole reaming. Then it's primed.

To measure case capacity, use the powder you'll be loading.

I fill to overflow with a drop tube, then weigh what's left in the case. That weight gets written onto the case wall with a Sharpie.

This measurement is the most direct way I can find to determine a meaningful case volume.

Water may be convenient (although I don't find that to be so), but I'm not loading my cases with water.

Greg

 

[mattmcg]

Re: Brass, is it all the same?

The only problem with using powder as a case measurement material is that it tends to settle and compact so the measurement can vary between tests. To overcome this issue, you can load up 20, take measurements and average the result which should get you much closer to the accurate value.

Water does not have these issues and using the concave/convex method takes out any issue of surface tension at the case opening.

I realize we're splitting hairs here so it depends upon your need for absolute precision. In the end, it may be 6 one way, a half dozen the other.....

 

[Greg Langelius *]

Re: Brass, is it all the same?

The issue was anticipated.

The drop tube creates a common denominator. Random blind testing confirmed repeatability, .223 through .30-'06. YMMV.

I also tried the water method and found that adding some detergent to the water resolved surface tension concerns; but the water was just too much mess, there was also the issue of having to dry the cases afterward, and using live primed cases was not an option.

Water also infiltrates the fired primer interior, and not especially consistently, so measurements can be questionable. The same is true of powder with live primers, but I did not find the inconsistencies I had expected.

...And then there's the small matter of my sweet Wife of 39 years making cracks about me playing with water like a five year old.

Greg

 

[BECKS7]

Re: Brass, is it all the same?

So then after working over our normal brass, would we get something as good as or close to off the shelf match brass?
I dont mean custom brass like nosler or lupia, I mean like black hills or hornady and federal

 

[Greg Langelius *]

Re: Brass, is it all the same?

I think so. Some brass has reputations for longevity problems, and IMHO, doing the work on them results in less for the effort, but on the whole, good prep and maintenance will deliver results very similar to the top line stuff. That's been both my mantra and my experience.

Greg

 

[BECKS7]

Re: Brass, is it all the same?

Exactly what I was looking to hear, thanks.