Taking the Leap
06-30-2009, 05:22 AM
#21
Guest
Posts: n/a
RE: Taking the Leap
ORIGINAL: Brush hunter
it was a few years back and i'm still looking for the data, however we used a chronograph, and mesured vel. We used 50 cases from the same lot all fired once. half were cleaned half were not, they were all loaded with the same bullets, primers and power from the same lots. the loads were all shot in 5 shot groups, the gun was cleaned after each group. The dirty rounds all fired between 5 to 8 flbs higher than the clean ones. it may not be 100% accurate, but I'm saying higher vel. =higher pressure.
ORIGINAL: bigcountry
Ok, do you have any pressure data? What was your technique for measureing pressure? Piezo, or Copper under pressure?
ORIGINAL: Brush hunter
Yes i do and have proven it.
Yes i do and have proven it.
06-30-2009, 05:51 AM
#22
Nontypical Buck
Join Date: Aug 2005
Location: S.W. Pa.-- Heart in North Central Pa. mountains-
Posts: 2,600
RE: Taking the Leap
ORIGINAL: bigcountry
Maybe, I can't really say 5-8fps is better than error of measurement. I have chono'd a lot of loads, I rarely see std dev. less than 8fps out of any load besides some very consistent 45ACP loads. I don't buy it, but I do respect that you are out there doing tests like these. I know I have done some off the wall tests which put biases in my mind. Most won't take the time to do tests on thier own and rely only on internet info or whats in books. So interesting tests.
ORIGINAL: Brush hunter
it was a few years back and i'm still looking for the data, however we used a chronograph, and mesured vel. We used 50 cases from the same lot all fired once. half were cleaned half were not, they were all loaded with the same bullets, primers and power from the same lots. the loads were all shot in 5 shot groups, the gun was cleaned after each group. The dirty rounds all fired between 5 to 8 flbs higher than the clean ones. it may not be 100% accurate, but I'm saying higher vel. =higher pressure.
ORIGINAL: bigcountry
Ok, do you have any pressure data? What was your technique for measureing pressure? Piezo, or Copper under pressure?
ORIGINAL: Brush hunter
Yes i do and have proven it.
Yes i do and have proven it.
.........Don't know what happened to my previous post. Went to edit it, and it disappeared.
Anyhow, I wondered if you have ever cut two casings apart at exactly the same place, say a given measurement from the head (one that has been fired once or not at all vs. one that has been loaded and fired to the point of being unreloadable anymore) and miked case wall thicknesses? Basically looking to see if a measureable buildup of residue was present. I'm sure you know various manufacturers can have different wall thicknesses also, and realize you stated you used the same manuf. and lot of cases. Also wondering if an analytical balance could show an increase in case weight with repeated firings..?? Primers would have to be weighed and separated so as not to invalidate reults, etc......
Also wondering if the 5-8 fps continues to multiply itself with repeated loadings? Is it incremental?
PS.....I should have sent this reply to Brush hunter, not big country.....
06-30-2009, 06:18 AM
#23
Nontypical Buck
Join Date: Nov 2008
Location: Adirondacks
Posts: 1,305
RE: Taking the Leap
It's not necessary to tumble case's.The cleaning media can "burn" to the inside of the case over repeated cleanings which changes the case's capacity resulting in different pressures.You do need to clean off the sizing lube and the powder residue from inside the neck area and primer pocket but that's all that's needed.
06-30-2009, 11:40 AM
#24
Nontypical Buck
Join Date: Aug 2005
Location: S.W. Pa.-- Heart in North Central Pa. mountains-
Posts: 2,600
RE: Taking the Leap
ORIGINAL: Bernie P.
It's not necessary to tumble case's.The cleaning media can "burn" to the inside of the case over repeated cleanings which changes the case's capacity resulting in different pressures.You do need to clean off the sizing lube and the powder residue from inside the neck area and primer pocket but that's all that's needed.
It's not necessary to tumble case's.The cleaning media can "burn" to the inside of the case over repeated cleanings which changes the case's capacity resulting in different pressures.You do need to clean off the sizing lube and the powder residue from inside the neck area and primer pocket but that's all that's needed.
.... or unlucky 
... Something very uniform and constant would have to be happening..... Just the way I see it...
07-05-2009, 08:15 PM
#25
Join Date: Jan 2005
Location: Somewere on Mt. St.Helens
Posts: 347
RE: Taking the Leap
ORIGINAL: Pawildman
I understand where you are coming from with this, Bernie. I do, however feel for tumbler media to cause the fps spread Brush hunter claims to see, it would almost have to be the same amount of media each time in each casing. I personally don't think you could possibly get that lucky .... or unlucky ... Something very uniform and constant would have to be happening..... Just the way I see it...
ORIGINAL: Bernie P.
It's not necessary to tumble case's.The cleaning media can "burn" to the inside of the case over repeated cleanings which changes the case's capacity resulting in different pressures.You do need to clean off the sizing lube and the powder residue from inside the neck area and primer pocket but that's all that's needed.
It's not necessary to tumble case's.The cleaning media can "burn" to the inside of the case over repeated cleanings which changes the case's capacity resulting in different pressures.You do need to clean off the sizing lube and the powder residue from inside the neck area and primer pocket but that's all that's needed.
.... or unlucky ... Something very uniform and constant would have to be happening..... Just the way I see it...
07-06-2009, 04:18 PM
#26
Nontypical Buck
Join Date: Aug 2005
Location: S.W. Pa.-- Heart in North Central Pa. mountains-
Posts: 2,600
RE: Taking the Leap
ORIGINAL: Brush hunter
I'm not talking about media build up, I'm talking about residue build up left in the case after fireing.
ORIGINAL: Pawildman
I understand where you are coming from with this, Bernie. I do, however feel for tumbler media to cause the fps spread Brush hunter claims to see, it would almost have to be the same amount of media each time in each casing. I personally don't think you could possibly get that lucky .... or unlucky ... Something very uniform and constant would have to be happening..... Just the way I see it...
ORIGINAL: Bernie P.
It's not necessary to tumble case's.The cleaning media can "burn" to the inside of the case over repeated cleanings which changes the case's capacity resulting in different pressures.You do need to clean off the sizing lube and the powder residue from inside the neck area and primer pocket but that's all that's needed.
It's not necessary to tumble case's.The cleaning media can "burn" to the inside of the case over repeated cleanings which changes the case's capacity resulting in different pressures.You do need to clean off the sizing lube and the powder residue from inside the neck area and primer pocket but that's all that's needed.
.... or unlucky ... Something very uniform and constant would have to be happening..... Just the way I see it...
.. I would like to know if the "big" shooters... the 1000 yd. guys give it any credence.... I flat know those guys are extremely diligent in their game. 
