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View Full Version : Red Dot vs Unique Pressure Curve for Ruger SAA 45LC



Walstr
03-12-2014, 08:55 PM
Greetings;

I'm now into Cowboy Action Shooting & loading low velocity 45LC 180gr lead, with 6gr Unique, because I have it. Lots of blowback. I have not setup to add the annealing process in hopes of softening the front 3/8" of the case to seal the chambers better?!?

Is it worth the search to obtain Red Dot to produce a faster pressure peak to flex my [mixed head] brass? What am I missing?

Zymurgy50
03-12-2014, 09:43 PM
Try firing the brass at a high enough pressure load to eliminate the blowback, then only size enough of the case to hold the boolit. Maybe a half inch or a bit more. No need to full length size 45lc brass for low pressure loads that will be fired in the same gun.

Walter Laich
03-12-2014, 09:52 PM
my problem is my Marlin chamber is very generous to say the least. If I don't fully size the cases they won't fit into my Ruger Vaqueros.
Course I do anneal my cases every 4-5 reload

JeffG
03-12-2014, 10:32 PM
I don't full length size mine either, sizing only the top ~ 3/8 inch, annealing the top 1/2 inch of the brass. That stopped any blowback. I typically use either 6.3 of Bullseye or 12 of Blue Dot behind Lee's 452-255 RNFP.

uscra112
03-12-2014, 11:08 PM
The pressure / time curve isn't that different. What will be different is that the peak pressure with Red Dot will be a bit higher than Unique, for any given muzzle velocity. But even that won't be dramatic. Annealing the brass would help a lot more than switching powder.

Walstr
03-13-2014, 10:46 AM
JEFFG, USCRA112; Aye, I was afeared I might have to get involved in the annealing process with these low pressures. Thanks for the straight up answers to my quandry. I understand Trail Boss ]or even Clays] is preferable over Unique for these small charges re: charge density & safety; but uscra112 cleared up my thoughts re: pressure peak vs sealing the chamber. Thanks to all in this fine forum for saving upstarts like me from reinventing the wheel 100 times over!

ANNEALING: I've done a little experimentation to see the effects & dropping cases into cold water for quenching really makes that brass soft as heck. I could squish the case mouth with my fingers. Without Brinell Hardness equipment to measure effectiveness, is there another way y'all have found that evaluates the result of amatuer annealing? I've seen Utube demo's that drop the cases into a bucket for "air quenching" with no mention of how the brass hardness was altered.

Thanks again for watching & play safe.

warf73
03-14-2014, 03:12 AM
Walstr,
I use Red Dot alot and can tell you from experiance that if you dont produce enough pressure you will get blow back even with Red Dot. I have a great low pressure load for 44mag that gets blow back (sooty cases) on all the cases. But its accurate and can be shot out of my EAA Bounty hunter all day long. Think its running around 875~925 FPS (240gr boolit)

Wally
03-14-2014, 07:02 AM
I imagine that you are using a carbide sizer die. I tried an RCBS steel sizer die and the problem was solved. The steel die does not size the back of the case as much as does the carbide. My Ruger BHK has generous chamber sizes and I find I am better off re-sizing the cases with a steel sizer die as the sized cases then fit better. On light Powder charges I routinely use a tuft of Dacron filler so that the powder is always to the rear end of the case...it works surprisingly well.

Wayne Smith
03-14-2014, 08:06 AM
Annealing - temperature alone anneals, the time is unimportant. Air cooling or water cooling will not affect how much the metal is annealed, but will potentially affect how much of the metal is annealed. Water cooling stops the annealing faster.

M-Tecs
03-14-2014, 08:52 AM
Some good info on how time and temperature effects annealing here:

http://www.lasc.us/CartridgeCaseAnnealing.htm

http://bisonballistics.com/articles/the-science-of-cartridge-brass-annealing

http://www.texas-mac.com/Annealing_Cartridge_Brass.html