M14 Forum


Samco’s Tumbled 7.62x51 Port

This is a discussion on Samco’s Tumbled 7.62x51 Port within the Ammunition forums, part of the M14 M1A Forum category; “FNM Portugal 1982-1983 FMJ, NC/BE, Brass cases, loose packed, tumbled, cleaned, minor tarnish.” Just received 1k rds @ .39c/rd shipped. I certainly would not call ...


Go Back   M14 Forum > M14 M1A Forum > Ammunition


2Thanks
Reply
 
LinkBack Moderator Tools Display Modes

Old November 27th, 2012, 08:14 PM   #1
Rifleman
 
Join Date: Aug 2009
Location: Nashville
Posts: 75
Samco’s Tumbled 7.62x51 Port

“FNM Portugal 1982-1983 FMJ, NC/BE, Brass cases, loose packed, tumbled, cleaned, minor tarnish.”

Just received 1k rds @ .39c/rd shipped. I certainly would not call this minor tarnish although I have inspected some closely under a magnifying glass and I cannot really detect any serious physical corrosion. Bullets and cases are smooth as virgin ammo. I dunno if I should make a fuss about returning it. I’d probably have to pay a chunk in one-way shipping.

I have heard Portuguese 7.62x51 is fine ammo but what about this?












GS455 is offline  
Remove Ads
Old November 27th, 2012, 08:17 PM   #2
In the gilded halls of Valhala
 
Dredsen's Avatar
 
Join Date: Jan 2012
Location: Texas
Posts: 11,779
THIS is the tumbled stuff?

id hate to see it before? think they were just pure green?

Dredsen is offline  
Old November 27th, 2012, 08:59 PM   #3
Dodgin' The Reaper
 
hammonje's Avatar
 
Join Date: Sep 2007
Location: Lilburn, GA
Posts: 7,154
I bought 10k rounds of Port Surplus in belts while the vast majority was still really clean. Samco replaced 1000+ rounds of it. And I was picky. I forced their hand to replace all of it for free b/c the description lacked any indication of possible corrosion. The very worst of the corroded rounds had black areas with blue/green copper sulfate in abundance. Mixed in were pink areas which makes the ammo unsafe. I had a blow out that made me cull any rounds from a corroded MEN NATO round. Pink areas are sometimes like powder as the zinc is nearly gone. I took notice after that. Dislodged the spring guide and that was it. Projectile struck 10" high so I knew the round was slow and went looking for the case. Perfect little hole.

I'd be asking those folks for a refund and a shipping label. The'll send you one if you call and don't act like a wimp while at the same time not acting accusatory. Give them an out and they'll take it.

One of the best descriptions of dezinctification I've read: About boat props but totally applicable

Brass composition: Reference Bronze is 98 copper/2 zinc

Brass, a metal that is almost synonymous with the sea, is actually a family of copper alloys whose primary ingredients, in varying ratios, are copper and zinc. In fact, some brasses are comprised of as much as 50 percent zinc. Some of the more common "seagoing" brasses are red brass: 85 percent copper, 15 percent zinc; cartridge brass: 70 percent copper, 30 percent zinc; Muntz metal: 60 percent copper, 40 percent zinc; admiralty brass: 70 percent copper, 30 percent zinc; naval brass: 60 percent copper, 40 percent zinc; aluminum brass: 76 percent copper, 22 percent zinc, 2 percent aluminum; and finally, manganese "bronze": 60 percent copper, 40 percent zinc. Because of its zinc content, manganese bronze is actually not bronze at all; it resides squarely in the brass family.

If its primary constituent is copper, why is brass so susceptible to corrosion? Because many of the brasses also contain a substantial amount of zinc, they are especially susceptible to a type of corrosion referred to as "dezincification." This is a process whereby the zinc selectively corrodes leaving a porous copper shell that retains its shape but little of its strength. A dezincified brass propeller can be identified by its splotchy reddish or pink coloring. Contrary to popular belief, many propellers are fabricated from a brass alloy (by definition, in order to be considered a true bronze, a copper alloy must contain little or no zinc) and, as such, are especially susceptible to dezincification. To protect this often-substantial investment, it is imperative that sacrificial zinc anodes be monitored and renewed when necessary. In a stainless steel/Aquamet shaft, brass propeller combination, once the zinc is gone the next least-noble metal (or metal most likely to corrode) is the brass prop. It will begin to corrode, sacrificing itself for the shaft, which is nobler. Brasses are susceptible to other forms of corrosion in addition to dezincification. Ammonia, a common ingredient of household cleaners, will readily attack brass, causing it to weaken and crack. Mercury is also an enemy of brass, as is the aforementioned polluted water.

hammonje is online now  
Old November 27th, 2012, 09:05 PM   #4
Platoon Commander
 
heyjowee's Avatar
 
Join Date: Feb 2011
Location: DFW
Posts: 446
I hope that wasn't tumbled/cleaned....

This is what mine looked like originally:


Cleaning progression from left to right:


Yellow circles were done with a dremel with the steel wire. Red was finished off with scotch-brite.


Finished off with the drill and scotch-brite. There is still a little pitting as seen.


About 95% of them ended up like this:


The few that did have minor pitting left after cleaning were set aside to use next time at the range. Ones that ended up looking new went into storage.

Drill, electrical tape on the jaws, and a scotch-brite pad gets them cleaned up way faster than a dremel.

I'm not an expert on the subject, but would advise you contact them and see if they shipped the non-tumbled ones and request a partial refund if you plan to keep/clean them.


Last edited by heyjowee; November 27th, 2012 at 09:24 PM.
heyjowee is offline  
Old November 27th, 2012, 09:33 PM   #5
Dodgin' The Reaper
 
hammonje's Avatar
 
Join Date: Sep 2007
Location: Lilburn, GA
Posts: 7,154
Wow.....there is no way I would shoot that nor use a rotary tool to remove corrosion. You are thinning the walls of an already weakened area. The corrosion may have significantly altered the chemical composition of the alloy and hence its overall properties. The corroded material lacks the plasticity of the original alloy and therefore exhibits less strength. It may be unable to resist the stretch/springback action of the original alloy and may fail catastophically from pressure alone. Honestly, I cannot comprehend why these companies would take the risk to put that material on the market.

I threw all my corroded rounds in a bucket of water for a month and then tossed them out.

hammonje is online now  
Old November 28th, 2012, 10:54 AM   #6
Rifleman
 
Join Date: Aug 2009
Location: Nashville
Posts: 75
Well I'm gonna dump a few mags this weekend. Samco said they would take back or exchange if there were any problems.

GS455 is offline  
Old November 28th, 2012, 11:25 AM   #7
Master Gunner
 
Duce's Avatar
 
Join Date: Jun 2012
Location: Twin Cities, MN
Posts: 862
Quote:
Originally Posted by heyjowee View Post
The above photo appears to be typical of the "corrosion" that is found on much of the recent SamcoPort offering. I detailed my experience in this post Heads up- Samco has PORT * CHEAP*
(see #41, #48 and #55 )

I've shot over 100 rounds of this stuff after I cleaned in the manner described, including the fugliest ones, with -ZERO- problems.

One thing I'd like to point out is the "corrosion" appears on both the case (brass) and the bullet (copper). If "dezincification" is in fact occurring, one would not expect to see the exact same type of corrosion on the copper jacketed bullet as is found on the brass case. Further, both before and after removing the "corrosion" on the rounds I worked with, I can't see or feel any deformities in the metal, whether it be on the bullet or casing. Nor did any of the "corrosion" find its way to the inside of the casing (as shown in post #51 of the aforementioned link) which one would expect if "dezincification" was in fact occurring. Based upon this, I am lead to believe that the "corrosion" may be a foreign substance that found its way onto the rounds, with said foreign substance later decaying/corroding to discolour the bullet and/or case with little to any interaction with the metal itself. With the rounds that I have worked with, I have yet to see any indication that the metal itself was in any way compromised.

Thanks from heyjowee
Duce is offline  
Old November 28th, 2012, 11:37 AM   #8
Dodgin' The Reaper
 
hammonje's Avatar
 
Join Date: Sep 2007
Location: Lilburn, GA
Posts: 7,154
Because many of the brasses also contain a substantial amount of zinc, they are especially susceptible to a type of corrosion referred to as "dezincification." This is a process whereby the zinc selectively corrodes leaving a porous copper shell that retains its shape but little of its strength.

If you see pink then it is dezinctification. I saw lots of pink and actually could scrape the material away with my fingernail as the metal was turned into a copper salt. I doubt that will reliably hold 50k PSI.

I trashed those rounds from my stash, every single last one that had any appreciable corrosion. Areas of black corrosion are not that much of a danger, but rounds with any areas of pink should be discarded or have the bullets pulled as components.

hammonje is online now  
Old November 28th, 2012, 11:37 AM   #9
Old Salt
 
Quicksilvergoat's Avatar
 
Join Date: Aug 2011
Location: ST MinnePaulis
Posts: 1,923
If I remember with. I get home later I'll post some photos of some close calls I had with old skunky ammo. Finding holes in the side of spent cases is unnerving.

Quicksilvergoat is online now  
Old November 28th, 2012, 11:47 AM   #10
Master Gunner
 
Duce's Avatar
 
Join Date: Jun 2012
Location: Twin Cities, MN
Posts: 862
Quote:
Originally Posted by hammonje View Post
Because many of the brasses also contain a substantial amount of zinc, they are especially susceptible to a type of corrosion referred to as "dezincification." This is a process whereby the zinc selectively corrodes leaving a porous copper shell that retains its shape but little of its strength.
And that was the point I attempted in my post above. You won't see dezincification on the bullet because the copper jacketed bullet contain no zinc. Yet the corrosion on the (zinc-less) bullet was the same as on the brass. Hence, I do not believe dezincification was the cause of the discoloration, but instead a foreign substance which found its way on both the case and the bullet.

Quote:
Originally Posted by hammonje View Post
If you see pink then it is dezinctification. I saw lots of pink and actually could scrape the material away with my fingernail as the metal was turned into a copper salt. I doubt that will reliably hold 50k PSI.
Again, as I've noted, I could not see or feel any abnormalities. While there was some discoloration after I cleaned the rounds, it appeared to be normal when compared to "trusted" rounds of, for example, HXP brass I threw in as a control. I even took a screwdriver to one of the worst looking Port cases and could not scrap anything came off it--at least in the form of a salt as you describe; if I scraped hard enough I could obviously scratch the brass itself.

Duce is offline  
Old November 28th, 2012, 01:26 PM   #11
Grunt
 
Join Date: Jan 2012
Location: Flint, MI
Posts: 85
Head over to this thread Heads up- Samco has PORT * CHEAP* to read up on what some of us did to clean these same rounds up real nice.

HeyGhost is offline  
Old November 28th, 2012, 02:56 PM   #12
Old Salt
 
Join Date: Mar 2006
Location: SAN FRANCISCO CALIF
Posts: 1,145
does anybody have direct knowledge of anybody having chambered a "corroded" round and having it blow the gun up..? not a friend of a friend of friend anecdotal rumor....

shotgun shells, although have much lower pressures are made of plastic or paper...cases split at the crimp after numerous reloadings..and they still go bang.

some of the reloading community neck turn their brass ...essentially weakening it structurally...and tumbling brass with corn cob or walnut shells is also brass against brass....maybe peening the brass....maybe .....and they still go bang.

I think that if the samco port has corrosion that has perforated the case....although cleaned from whatever method.....will still go bang because the rifle chamber will contain the pressure from the firing eventhough the case is perforated or split.

in the above situation, what would cause the barrel to blow up would generally be from an obstructed barrel not because the case is split or perforated. This applies to "factory" ammo not somebody's favorite hand load. Maybe a severly corroded bullet could have dimensional changes that could cause higher pressures....so maybe it would be more important to remove the corrosion from the bullet...and then the casing is really a secondary issue. Corroded cases can cause feeding problems and chambering problems...clean an smooth is good

just some of my thoughts....and observations.....not conclusions...

Mocos is offline  
Old November 28th, 2012, 03:27 PM   #13
Lifer
 
Join Date: Sep 2007
Location: Indiana
Posts: 2,348
If this stuff was so great the country of origin would still have it in inventory. I don't know anybody who has had problems with this crap and it for sure ain't gonna be me. If you've gone thru 10K with no problems great but the next one.....who knows. And TUMBLED to boot. Bad on two counts. Somebody buy all this junk up and maybe the next restock will be some good surplus.

Wayne M is offline  
Old November 28th, 2012, 04:30 PM   #14
Old Salt
 
brycom1's Avatar
 
Join Date: Feb 2007
Location: CO
Posts: 1,426
Thats a bit corroded for me. I'm usually not the anal one one this site either..

As far as being tumbled it has no ill affect on the powder. I tumble ammo all the time and have no problems.

http://www.ar15.com/forums/t_1_5/989...nds_in_OP.html

brycom1 is offline  
Old November 28th, 2012, 04:33 PM   #15
In the gilded halls of Valhala
 
Dredsen's Avatar
 
Join Date: Jan 2012
Location: Texas
Posts: 11,779
so dont shoot that stuff !?!

right?

Dredsen is offline  
Reply

  M14 Forum > M14 M1A Forum > Ammunition



Search tags for this page

1983 portuguese 7.62 x 51

,

7.62x51 fnm portugal

,
7.62x51 samco
,
black gun ammo 7.62x51
,
fnm 7.62 59
,

how to clean fnm 7.62x51 with black spots

,
portuguese 7.62 clean
,

portuguese 7.62 nato

,
portuguese 7.62 x 51 ammo lot number 80 11 what type is bullet
,
portuguese 7.62x51 m1a
,

replacing portuguese 7.62x51 nato ammo with lighter bullet

,

tumble corroded ammo

Click on a term to search for related topics.

Moderator Tools
Display Modes


Similar M14 Forum Discussions
Thread Thread Starter Forum Replies Last Post
7.62x51 NATO -- Port and German in .50 cal Cans *$30 flat rate shipping/can CONUS* Evildoer SPF 30 July 5th, 2012 05:35 PM
Port & Aussie 7.62x51 @ .39 / rnd junion Ammunition 0 January 31st, 2007 04:17 AM
NATO marked Port. vs SA 7.62X51 leid Ammunition 6 February 11th, 2006 05:44 PM



Top Gun Sites Top Sites List