checking volume of brass

[cohunt]

http://blog.joehuffman.org/2014/10/19/experiments-with-oil-and-primers/

https://www.bevfitchett.us/ballistics/priming-compounds-and-primers-introduction.html

 

[Steve Sheasly]

http://blog.joehuffman.org/2014/10/19/experiments-with-oil-and-primers/

Thank you I had read this earlier but alcohol is not one of the solvent used I guess I can't read my own experiment like this one I was going to talk to CCI today but it's Veterans Day I forgot and I'm a veteran I think I'm getting CRS

 

[cohunt]

have you tried firing one yet? they may not have actually gotten wet-- I linked those as one of the points made was that a pressed in primer actually may have an air pocket above it when filled with liquid--notice that when the oil was put into the case then emptied , most of the primers went off---but when the primers were soaked in fluid, it was more likely that the primer was affected and would not fire

each company seems to use a "proprietary" primer compound so testing the brand you intend to use would be your best bet

I'm going to bet that cci tells you not to fire them (for liability reasons)

 

[Steve Sheasly]

CCI said at first it would not hurt the primer then when they found out I was going to use it and not replace it --- they reversed course and said anything that touches the primer will cause it to fail.So I think it might work but you are right liability is an issue. With out them saying so. It is tacit knowlege

 

[Pdvdh]

Test it out, with no powder. Just fire off the primer.

I'll be surprised if you get much of a bang.

Anything that softens the primer media will reduce the 'impact' from the firing pin strike. Striking mud versus firing pin striking concrete. Hard to get a solid impact striking jello.

The prior article linked already tested water, and water killed the primers. Rubbing alcohol is water + alcohol.

 

[Steve Sheasly]

yes either 30 percent or 5%. Pure alcohol was still out of bounds for CCI. I got the answer that I was looking for. I will purchase plugs and measure that way. Peterson cases is getting back to me on accuracy and case volume vs weight.

 

[osok-1k]

Used or new primers will have an effect on water volume in that there is a crater in the primer, so if you are going to the nth degree you must take the primer pocket out of the equation by using a plug to fill the pocket. Flash hole uniformity could be a factor as well. I assume you're zeroing your scale with the case on the scale and measuring strictly water weight.

 

[Steve Sheasly]

Used or new primers will have an effect on water volume in that there is a crater in the primer, so if you are going to the nth degree you must take the primer pocket out of the equation by using a plug to fill the pocket. Flash hole uniformity could be a factor as well. I assume you're zeroing your scale with the case on the scale and measuring strictly water weight.

Yes but water has a concave meniscus and alcohol has a convex which always,is,precise in,overflow easy to read and get repeatable results. 10 same case weights completely repeatable

 

[Steve Sheasly]

Test it out, with no powder. Just fire off the primer.

I'll be surprised if you get much of a bang.

Anything that softens the primer media will reduce the 'impact' from the firing pin strike. Striking mud versus firing pin striking concrete. Hard to get a solid impact striking jello.

The prior article linked already tested water, and water killed the primers. Rubbing alcohol is water + alcohol.

got a nice bang no difference to new

 

[Steve Sheasly]

No kidding, why risk a hunt over pennies?

ok so here is what the "experts" had to say. Nosler, Hornady, Peterson, Norma, Federal/CCI

1. there is no consistent correlation of weight to volume.
a. the main reason is the cup for extrusion of the case is cut from a brass sheet -- the sheet has different densities of brass intrinsically so he head can have significant weight variances from head to head.
b. the extractor grooves and belts are machined this cannot be precise.
c. Head stamping displaces brass

2. consensus: up to 3 grains of volume difference may not affect he accuracy (I disagree and will do testing)

3. Primeres will foul if touched or if the phase of the moon is wrong -- testing me -- they will shoot well if soaked in alcohol --- I will not chance it --- $18k vs .002 cents not worth the loss of an Ibex.

4. Volume sorting takes more time. If you want an extremely accurate round you must volume sort. If you can live with a less accurate round weigt sort -- will it make a difference yes -- a .22 caliber will kill a lion or a moose if it is placed exactly right. An animal can survive a large caliber wound long enough to make your life hell if you do not hit the intended spot.

5. I will take the extra hour to volume sort.

Thanks to all for the input.

 

[Pdvdh]

got a nice bang no difference to new

Next step = powder, bullets, and chronograph. If it's still good, I'll start storing CCI primers in rubbing alcohol...

 

[Steve Sheasly]

Not rubbing,alcohol 200 proof 100 percent alcohol (walgreens) . I am going,to,buy the precision plugs .But,I think alcohol would work. I know for sure it is an accurate measurement media.

Nextstep = powder, bullets, and chronograph. If it's still good, I'll start storing CCI primers in rubbing alcohol...

 

[FURMAN]

ok so here is what the "experts" had to say. Nosler, Hornady, Peterson, Norma, Federal/CCI

1. there is no consistent correlation of weight to volume.
a. the main reason is the cup for extrusion of the case is cut from a brass sheet -- the sheet has different densities of brass intrinsically so he head can have significant weight variances from head to head.
b. the extractor grooves and belts are machined this cannot be precise.
c. Head stamping displaces brass

2. consensus: up to 3 grains of volume difference may not affect he accuracy (I disagree and will do testing)

3. Primeres will foul if touched or if the phase of the moon is wrong -- testing me -- they will shoot well if soaked in alcohol --- I will not chance it --- $18k vs .002 cents not worth the loss of an Ibex.

4. Volume sorting takes more time. If you want an extremely accurate round you must volume sort. If you can live with a less accurate round weigt sort -- will it make a difference yes -- a .22 caliber will kill a lion or a moose if it is placed exactly right. An animal can survive a large caliber wound long enough to make your life hell if you do not hit the intended spot.

5. I will take the extra hour to volume sort.

Thanks to all for the input.

I'm telling you this is bs with every case I've measured with both methods. The es and sd of weight and volume is near identical. The manufacturers can say what they want but I've measured. Again do what you need for your own confidence.

 

[WildRose]

ok so here is what the "experts" had to say. Nosler, Hornady, Peterson, Norma, Federal/CCI

1. there is no consistent correlation of weight to volume.
a. the main reason is the cup for extrusion of the case is cut from a brass sheet -- the sheet has different densities of brass intrinsically so he head can have significant weight variances from head to head.
b. the extractor grooves and belts are machined this cannot be precise.
c. Head stamping displaces brass

2. consensus: up to 3 grains of volume difference may not affect he accuracy (I disagree and will do testing)

3. Primeres will foul if touched or if the phase of the moon is wrong -- testing me -- they will shoot well if soaked in alcohol --- I will not chance it --- $18k vs .002 cents not worth the loss of an Ibex.

4. Volume sorting takes more time. If you want an extremely accurate round you must volume sort. If you can live with a less accurate round weigt sort -- will it make a difference yes -- a .22 caliber will kill a lion or a moose if it is placed exactly right. An animal can survive a large caliber wound long enough to make your life hell if you do not hit the intended spot.

5. I will take the extra hour to volume sort.

Thanks to all for the input.

I've talked to a whole lot of actual experts at several of those companies over the years and not one of them has said that.

Nosler in fact charges extra for their fully prepped and weight sorted brass.

Variations in wall, shoulder, and neck thickness mean differences in weight and they also will correspond to differences in volume.

Sort, don't sort, sort by weight, sort by liquid volume, whatever suits you but let's don't have any more passing off of bad information as gospel. It doesn't help anyone.

For the average hunter and reloader it probably won't make enough difference to matter but then they are just trying to hit a 10" target at a maximum of 200yds.

For long range precision shooting it's one more variable that is within our control so it's worth doing.