Armscor brass
Printed From: The Carbine Collector's Club
Category: The Club
Forum Name: Safety/ Accuracy/Shooting/Ammunition/Care and Maintenance
Forum Description: What to Check, Reloading, Tips for Accuracy, Competitive/Recreational Shooting
URL: http://www.uscarbinecal30.com/forum/forum_posts.asp?TID=6256
Printed Date: Apr 16 2024 at 12:11am
Software Version: Web Wiz Forums 12.01 - http://www.webwizforums.com
Topic: Armscor brass
Posted By: Sawbones
Subject: Armscor brass
Date Posted: Jun 27 2022 at 2:08pm
|
Just rec'd. a bag of spent 30cal brass, mixed head stamps, some of which are not even readable. All greased brass de-primed and sized w/ standard RCBS full length sizing die w/o issue. All easily processed through Lee length sizer "cutter" tool save for brass head stamped "A USA" which is the ARMSCOR head stamp. Save for the ARMSCOR brass all inner diameters at mouth of brass measured 0.30". All ARMSCOR brass measured 0.2.93-0.298" hence would not fit onto Lee length cutter sizer. (outer diameters consistently 0.325") I ran the ARMSCOR thru the RCBS full length sizer again w/ same results. OBSERVATION: The RCBS full length sizer sized non-ARMSCOR brass to 0.30" inner diameter at mouth of case and all ARMSCOR to < 0.298". Can anyone 'splain this? ------------- "Always do sober what you said you'd do drunk. That will teach you to keep your mouth shut." Ernest Hemingway |
Replies:
Posted By: blackfish
Date Posted: Jun 27 2022 at 3:53pm
| Spring-back of ARMSCOR's thicker brass from the die is more than the thinner brass of the other stuff? |
Posted By: Sawbones
Date Posted: Jun 27 2022 at 4:08pm
|
Sounds reasonable but walls of non-Amscor are 0.012" and walls Amscor are a variable 0.012-0.014", mostly 0.012-0.013, not an appreciable difference. Must be some pretty sorry brass if there is indeed a "springback". Didn't know there could be 'springback' but I can't think of any othe reason. . ------------- "Always do sober what you said you'd do drunk. That will teach you to keep your mouth shut." Ernest Hemingway |
Posted By: blackfish
Date Posted: Jun 28 2022 at 12:10pm
You measure (posted above) OD = 0.325 ID = 0.293-0.295 (call it 0.294 to keep the math simple) wall thickness = (OD - ID) / 2 = 0.016 which is appreciably different (30%) from your "weaker" brass Anything deformed exhibits springback over its range of elastic deformation. Bend a wire. Most of your transformation is inelastic so wire for mot part holds its shape. Springback means you have to over-bend to achieve the desired shape. Springback is important for more than just bending wires properly. When you fire a cartridge in a chamber, pressure expands your brass case to provide a gas-tight seal against the chamber walls. When that pressure is released after bullet exits the bore, springback of the brass allows the case to be easily removed by the extractor. It definitely saves you the trouble of having to bring a mallet and a rod to the range. |
Sawbones wrote:Posted By: Sawbones
Date Posted: Jun 28 2022 at 12:50pm
|
I hear what you are saying and agree with you. However, thick, thin or otherwise, cartridge brass metallurgy by design is not supposed to have a "springback" of the magnitude of this Armscor brass , presumably, because none of the other brands of cases do. Armscor brass is unique in this regard. Of the thousands and thousands of rounds in myriad calibers I've re-loaded over a period of almost 40 years this is my first experience with this "springback" during the re-sizing process. The fact the Armscor brass anomaly I am experiencing (as well as others on this Forum), coupled with the critical analysis of members of several of the re-loading Forums relating to the Armscor brass, I would say the take home message here is the metal content in this Armscor brass is sub-par with that of the standard of the industry. ------------- "Always do sober what you said you'd do drunk. That will teach you to keep your mouth shut." Ernest Hemingway |
Posted By: Smokpole
Date Posted: Jun 28 2022 at 4:28pm
|
I've had too many problems with their brass over the years; hence, it automatically goes to the scrap brass bucket. ------------- OGCA Life member NRA Life member Ashtabula Rod and Gun Life member |