The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > Handloading, Reloading, and Bullet Casting

Reply
 
Thread Tools
Old January 11, 2007, 02:04 PM   #1
herbie53
Member
 
Join Date: October 15, 2006
Posts: 47
PCBS Uniflow

I just recently bought a Uniflow and have been getting used to throwing charges and then weighing them to make sure I'm doing it right.

I seem to vary by a 1/10th or 2/10 either way every few charges. Is this normal? Would the powder baffle inside the powder chamber make any difference.

I normally wouldn't quibble, but I was expecting a bit more consistency. This way my 4.5 of Bullseye may be 4.4, 4.6 or what have you.

Any advice?

Thanks

Bryan
herbie53 is offline  
Old January 11, 2007, 03:14 PM   #2
Dave R
Senior Member
 
Join Date: January 7, 2000
Location: Idaho
Posts: 6,073
Is your Uniflow brand new? I've heard you have to throw several hundred charges through them to "break them in."

I bought mine used, and it occasionally varies by 1/10 of a grain, depending on the powder. Ball powders it doesn't even vary a tenth. Stick powders and big flakes can vary a tenth, on occasion.

Also, you have to be careful to move the throwing arm the same way each time. I believe the manual discusses that. Variations in the way you move the arm can affect the weight of the charge thrown.
__________________
I am Pro-Rights (on gun issues).
Dave R is offline  
Old January 11, 2007, 03:23 PM   #3
herbie53
Member
 
Join Date: October 15, 2006
Posts: 47
New Uniflow

It's a very new toy.

So I maybe have to run a bunch of powder through to break things in? Interesting. I did note that you wanted to move the handle in the same fashion each time.

Given that we're supposed to get yet another snowstorm, I might be able to have the time to do that

Bryan
herbie53 is offline  
Old January 11, 2007, 03:43 PM   #4
bigautomatic
Senior Member
 
Join Date: December 18, 2005
Location: Ohio
Posts: 610
I made a baffle for mine (just copied the original) and it definately made a difference in charge weight consistancy. Without a baffle, the weight of the powder inside the unit decreases every time every time you throw a charge.
bigautomatic is offline  
Old January 11, 2007, 07:34 PM   #5
carl418
Senior Member
 
Join Date: February 20, 2006
Location: north Ga
Posts: 208
Mine sometimes will throw under, then the amount that charge was under is in with the next charge; in other words, two cases with one way under and the next one way over. It's easy to catch, but I wish I didn't have to deal with it.

Would a baffle help that problem? And, how did you make it?

Sorry... not trying to steal this thread!
__________________
-NRA life member-
Visit NRANews.com
carl418 is offline  
Old January 11, 2007, 09:24 PM   #6
cheygriz
Senior Member
 
Join Date: May 11, 2002
Location: high up in the rockies
Posts: 2,232
One or two tenths? I wouldn't worry about it.
__________________
If you think a mighty military force is expensive, wait 'til you see what a weak one costs.
cheygriz is offline  
Old January 11, 2007, 09:46 PM   #7
drvector
Member
 
Join Date: March 28, 2005
Location: Northeast
Posts: 69
powder baffle

Get the powder baffle… I had the same problem with my uniflow until I put the powder baffle in, it made a big difference. It's not perfect, I still measure every tenth load or so, but it is significantly better than not having one.
__________________
Regards kdb
drvector is offline  
Old January 12, 2007, 02:45 PM   #8
Dave R
Senior Member
 
Join Date: January 7, 2000
Location: Idaho
Posts: 6,073
One other thought...

If you have a large arbor, and you're throwing small charges for pistols, its not going to be as accurate as the small arbor.

If you don't know whether you have a large arbor...how big a charge can you throw? If you can throw a 40gr. charge, you have a large arbor. Get a small arbor for small pistol charges.
__________________
I am Pro-Rights (on gun issues).
Dave R is offline  
Old January 13, 2007, 08:11 PM   #9
bigautomatic
Senior Member
 
Join Date: December 18, 2005
Location: Ohio
Posts: 610
Carl418,
I just went by a picture of the RCBS baffle, and used a piece of sheetmetal and tin snips. It did take some trial and error, to get it to fit in the cylinder but it doesn't have to be exact. The principal is to have the same weight of powder sitting on top of the arbor every time you throw a charge, and the baffle will help keep that weight consistent. Took me all of 15 minutes to make the baffle.
bigautomatic is offline  
Old January 15, 2007, 11:21 AM   #10
MADISON
Senior Member
 
Join Date: January 1, 2000
Location: Roanoke, Virginia
Posts: 2,678
RCBS Uni-Flo

1/10th or 2/10 either way is exceptional consistancy.
I have owned a Uni-Flo for 37 years and love it. I use an old PACIFIC/Hornady pistol powder measure and LEE disk powder measures for pistol loadings.
MADISON is offline  
Old January 15, 2007, 12:05 PM   #11
Edward429451
Junior member
 
Join Date: November 12, 2000
Location: Colorado Springs, Colorado
Posts: 9,494
I agree, 1 or 2 10'ths isn't enough to be concerned about unless you're loading near max in which case you'd be trickling them up to precise weight anyway.

When I get a new jug of powder, I set it and throw 10 charges to get an average, and plug the info into the chronograph math sheet, record the extreme spread, avg spread and so forth. I then scotch tape this info onto the powder jug. (I also weigh one charge where the measure is tapped / bumped to let me know what I could expect in overage if something unforseen happens.) Also record which measure the test was done on (RCBS-DILLON-etc.)
Edward429451 is offline  
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 05:06 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2014 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Contact Us
Page generated in 0.08562 seconds with 9 queries