Modern Sporting Rifle Evolution
Sign up Calendar Latest Topics
 
 
 


Reply
  Author   Comment  
kdbarker

Avatar / Picture

Moderator
Registered:
Posts: 543
Reply with quote  #1 
These are critical first steps to make sure your brass is sized correctly. If you are having problems with your first batch of brass, make sure you are following these directions precisely because if your brass is sized too short it will fail to fire, too long and the bolt will not lock into battery and you have a fail to fire.

Wade has described this in detail, but I thought it was worth reposting. This is his directions with a few of my photos...

"Starting with LC 5.56 once fired brass.

Resize using the mongoose size die with a .010" space between the shell holder and the die. This can be accomplished with a +.010" redding shell holder from their comp. shell holder set, or by using a shim between the die base and the top of the shell holder, or by backing off the die to create the gap (least likely to give consistent results).

Trim brass to 1.690", chamfer and de-burr and remove primer crimp if not already removed.

Try to chamber your newly formed piece of brass in your rifle.

Does it go easily into battery (see photo)?

If yes then go on ahead with your loading procedure.

If no then set this case to the side and start over with a new piece of brass and reduce the space between the shell holder and the die to .008" with whichever method you selected on the first piece of brass.

Keep reducing the space between the shell holder and die and resize with a new piece of brass until your brass closes in the chamber without too much effort. Always be sure to keep the trim length to 1.690" which is max case length.

The reason for using a new piece of brass each time is because the brass that you just sized will not want to move with the .002" bump that you create when reducing the gap. It will likely try to spring back to where it was on the first sizing. Just set it to the side and start with a new piece.

Once you have your die/shell holder set so that your brass will chamber you can now go ahead and start loading whichever bullet/powder/primer combination that you want.

Once you have some loaded the neck diameters need to be checked to make sure there will be no interference in the chamber. The maximum diameter that a loaded neck can be is .269". the chamber neck is .271" so you will need .002" minimum room in order for the bullet to release cleanly from the neck and not create a high pressure situation.
The chamber reamer dims are set around LC brass as the parent and its neck thickness.  All of the LC brass that I have used clears the neck with some room to spare. Some other manufactures might not work without neck turning. Those need to be checked near the neck/shoulder jct. to be sure. I know for sure Lapua necks will need to be turned because of how thick the shoulders are on them. I also checked some TA surplus brass that was close to .269" after loading. So I turn those two manufactures brass for sure before loading them.

From all of the load data that I have seen, the published data (not data from Joe Blow off the internet) from various sources are showing max loads for 6x45mm to be midrange loads for the Mongoose. I have been going half way between max and min for the 6x45, start my ladders there and work up. I have been ending up around a grain or two over max listed loads for the 6x45.

As you all know, there is not a max length for it - aside from fitting into an AR15 magazine. You will have to determine where your length needs to be based on your projectile choice. We can't just load to 2.2XX" and call it good because some projectiles will be into the lands at a shorter OAL. You will need a modified case, or use some other method to determine where your projectiles hit the lands and load accordingly.


One very important thing for any ammunition, hand-loaded of factory! If you have a loaded  cartridge that does not go into battery, do not force it into battery. Something is wrong with it. set it to the side and take some measurements later. It could be a thick neck, loaded too long, jacked up case. Just don't try to force it to shoot. It can bite you!"

Setting up your sizing die: Start long and adjusted sizing die down (less cartridge headspace) until the bolt locks up with little effort.
It helps to remove the ejector and extractor from your bolt for this step to get a more precise measurement, but its not all together necessary; I just feel its easier this way.

One last thing... make sure you chamfer the inside case neck real good before seating a bullet!  The 40 degree shoulder offers little support for any downward pressure on the neck, and if the cases have just been annealed its easy to collapse the shoulder while seating a bullet.  


 sizing die setup.jpg


__________________

Firearms Instructor Certification and Metallic Cartridge Reloading Instructor. Background in Gunsmithing/Armorer, and Shooting Range Development and Management.
"Where there is no counsel, the people fall: but in the multitude of counsellors there is safety"...

 

0
Talenel

First 50
Registered:
Posts: 727
Reply with quote  #2 
Should I anneal the case first to make it more pliable, like the new brass?
0
kdbarker

Avatar / Picture

Moderator
Registered:
Posts: 543
Reply with quote  #3 
I've tried both ways, annealing before or after forming. Both have benefits and drawbacks.
For fresh once fired LC or new brass, I would anneal, size, fire form, then you can reload again without annealing.
Some find it easier to size first, then anneal... personal preference and what works best for your setup.

__________________

Firearms Instructor Certification and Metallic Cartridge Reloading Instructor. Background in Gunsmithing/Armorer, and Shooting Range Development and Management.
"Where there is no counsel, the people fall: but in the multitude of counsellors there is safety"...

 

0
RangerJoe

Avatar / Picture

Administrator
Registered:
Posts: 4,177
Reply with quote  #4 
Annealing first definitely reduces the spring-back, especially with GI brass, which yielded more consistent results for me.  The down side is that shoulders are easier to collapse.
__________________
Sua Sponte | Ranger Joe
0
lapriester

Avatar / Picture

MSR Enthusiast
Registered:
Posts: 324
Reply with quote  #5 
Question and assumptions. I have begun forming Mongoose brass from the once shot stuff I got from Keith last week. I annealed some and left some alone during my first efforts.

Questions: 1) When I form the brass I get a slight bell at the shoulder. Is this normal pre fire forming? I'm assuming so since no matter what I've tried it's still there. It is formed when the shoulder is pushed back and not by the expander button or lack of inside neck lube. That was the first thing I checked. No bell when only the button is run in the mouth.

2) I followed the above sizer adjustment procedure starting long and working down and found the die had to be run all the way down to a cam over on my Rockchucker for the formed and trimmed case to easily chamber. Unusual? That bell mentioned above did not seem to effect easy clambering. That's why I assume it's "normal" on initial forming.

Oh, snd it doesn't seem to matter a bit whether the cases are annealed or not. The slight bell is always there. See the pic I attached.

Attached Images
jpeg 20181228_163934.jpg (123.10 KB, 11 views)

0
lapriester

Avatar / Picture

MSR Enthusiast
Registered:
Posts: 324
Reply with quote  #6 
Here's a closer cropped view.

Attached Images
jpeg 20181228_165930.jpg (173.51 KB, 5 views)

0
MDWS

Avatar / Picture

ADMINISTRATOR
Registered:
Posts: 5,435
Reply with quote  #7 
The small bell is totally normal for first form, unless all the planets align for you... the final body/shoulder junction is wider than the original of the parent case.

I can't speculate on your dies/press/cam without being there but you should have a little more wiggle room than that.

__________________

Don't mistake kindness for weakness...

We are charged with upholding the constitution, from all threats, foreign or domestic, and we will bear true faith and allegiance to the same.

-Mark
0
lapriester

Avatar / Picture

MSR Enthusiast
Registered:
Posts: 324
Reply with quote  #8 
Quote:
Originally Posted by MDWS
The small bell is totally normal for first form, unless all the planets align for you... the final body/shoulder junction is wider than the original of the parent case.

I can't speculate on your dies/press/cam without being there but you should have a little more wiggle room than that.

Thanks. That's what I thought. When I had the die back where it barely touched the bolt closed but was very tight. Enough so it had to be slammed closed and was very hard to get back open. Much better with the cam over. I think I'll just size like I have it set and adjust setback after initial fire forming to about .003-.004 with that dandy Hornady tool you talked me into buying.😉

So, should I anneal before or after initial forming? I noticed the expander button is noticebly easier to get through the neck if annealed first. That probably will minimize any springback issues I might encounter with fresh once fired brass.
0
MDWS

Avatar / Picture

ADMINISTRATOR
Registered:
Posts: 5,435
Reply with quote  #9 
Quote:
Originally Posted by lapriester
Thanks. That's what I thought. When I had the die back where it barely touched the bolt closed but was very tight. Enough so it had to be slammed closed and was very hard to get back open. Much better with the cam over. I think I'll just size like I have it set and adjust setback after initial fire forming to about .003-.004 with that dandy Hornady tool you talked me into buying.😉

So, should I anneal before or after initial forming? I noticed the expander button is noticebly easier to get through the neck if annealed first. That probably will minimize any springback issues I might encounter with fresh once fired brass.

No need to anneal... go shoot it and your brass will be much, much better looking and performing.  Annealing never hurts, just like checking your tire pressure every time before you drive.

__________________

Don't mistake kindness for weakness...

We are charged with upholding the constitution, from all threats, foreign or domestic, and we will bear true faith and allegiance to the same.

-Mark
0
RangerJoe

Avatar / Picture

Administrator
Registered:
Posts: 4,177
Reply with quote  #10 
Larry - I've had more problems with collapsed cases when annealing before the initial sizing; therefore I've been annealing after forming for the Mongoose and Ocelot.  I also have to trim my brass before sizing or I get problems.  Each set of Mongoose dies are virtually "custom".  As others have said - the "donut top" is perfectly normal and vanishes with the initial fire-forming.  Happy New Year!
__________________
Sua Sponte | Ranger Joe
0
lapriester

Avatar / Picture

MSR Enthusiast
Registered:
Posts: 324
Reply with quote  #11 
LOL. Since I've never annealed anything in my life before that fits right in. Besides all I have is the backyard redneck inconsistent method using a drill, socket and propane torch. With LC brass so common I could care less about longevity. I probably have close to 2K unprocessed range pickup on the shelf already. And about 3K RP and WCC.

Thanks for the input.

Happy New Year all.
0
lapriester

Avatar / Picture

MSR Enthusiast
Registered:
Posts: 324
Reply with quote  #12 
One thing I noticed is this caliber looks a whole lot like a 6mm TCU except the TCU, like the 6x45, retains the 223/5.56 1.750 case length.
0
MDWS

Avatar / Picture

ADMINISTRATOR
Registered:
Posts: 5,435
Reply with quote  #13 
Quote:
Originally Posted by lapriester
One thing I noticed is this caliber looks a whole lot like a 6mm TCU except the TCU, like the 6x45, retains the 223/5.56 1.750 case length.

It is sort of a shortened TCU, yes

__________________

Don't mistake kindness for weakness...

We are charged with upholding the constitution, from all threats, foreign or domestic, and we will bear true faith and allegiance to the same.

-Mark
0
Rifter

Avatar / Picture

First 50
Registered:
Posts: 1,187
Reply with quote  #14 
Quote:
Originally Posted by lapriester
Thanks. That's what I thought. When I had the die back where it barely touched the bolt closed but was very tight. Enough so it had to be slammed closed and was very hard to get back open. Much better with the cam over. I think I'll just size like I have it set and adjust setback after initial fire forming to about .003-.004 with that dandy Hornady tool you talked me into buying.😉

So, should I anneal before or after initial forming? I noticed the expander button is noticebly easier to get through the neck if annealed first. That probably will minimize any springback issues I might encounter with fresh once fired brass.

I would recommend that you shave about .010-.015" from the bottom of the die to give better adjustment range, and to avoid having to cam over.  All that does is put extra wear on the toggle bearing.

__________________
Extremism in the defense of Liberty is no vice.  Barry Goldwater
When Injustice becomes Law, Resistance becomes Duty.  Thomas Jefferson
NRA Benefactor Life Member
ISRA member
0
lapriester

Avatar / Picture

MSR Enthusiast
Registered:
Posts: 324
Reply with quote  #15 
Born today. 250 formed Mongoose from that 500 LC I won in the drawing from Keith. 250 more to be born soon. I forgot how much I hate forming, trimming and prepping brass. At least this is one step less than Wolverine. No cutting. Now to get the upper put together so I can load and fire form. That may be awhile though. I want to sponge camo this rifle using Aluma Hyde and it's going to have to get a lot warmer before I can.

Attached Images
jpeg 20181231_194451.jpg (182.37 KB, 5 views)

0
lapriester

Avatar / Picture

MSR Enthusiast
Registered:
Posts: 324
Reply with quote  #16 
Decided I can't wait to put together the Mongoose. I was going to wait for warm weather so I could camo paint it. So, couldn't stand that long wait and I orderd a set of Gun Skins for it. I've never tried them before so wish me luck. They get lots of 5 star reviews so we'll see. DVOR had them for $50 so I couldn't resist. I want to load and fire form the newly formed LC's with those 55gr Dogtowns and what better time to do that than killing squirrels in March. Much more fun than killing paper and dirt.
0
OldVet

Avatar / Picture

Member
Registered:
Posts: 31
Reply with quote  #17 
With my antique Herter's press, I set the resizing die to lightly kiss the shell holder and then inserted a .010 shim under the locking ring. I worked down to a .003 shim before I finally hit the shoulder length I needed to chamber. They measure 1.428 - 1.429 with my Hornady case length comparator. Fired cases measure 1.4315 - 1.432 before resizing. It's supposed to be pretty rainy here all next week, so it may be a bit before I can check them out at the range.
0
OldVet

Avatar / Picture

Member
Registered:
Posts: 31
Reply with quote  #18 
FYI...

I received a batch of "mixed" NATO 5.56 brass, WCC and TAA head stamps. TAA is from Taiwan and, like Lapua, will have a thicker neck than desired for the Mongoose. It will read .268-.269 at the neck base when formed with no bullet seated and needs to be turned.
0
MDWS

Avatar / Picture

ADMINISTRATOR
Registered:
Posts: 5,435
Reply with quote  #19 
I've never had luck with the TAA brass...
__________________

Don't mistake kindness for weakness...

We are charged with upholding the constitution, from all threats, foreign or domestic, and we will bear true faith and allegiance to the same.

-Mark
0
RangerJoe

Avatar / Picture

Administrator
Registered:
Posts: 4,177
Reply with quote  #20 
Quote:
Originally Posted by MDWS
I've never had luck with the TAA brass...
Ditto!  Had intermittent neck thickness problems with PMC brass too.  I basically give away (i.e., load throw away-brass range ammo for my sons) with anything but US GI 5.56 brass these days.

__________________
Sua Sponte | Ranger Joe
0
OldVet

Avatar / Picture

Member
Registered:
Posts: 31
Reply with quote  #21 
Quote:
Originally Posted by MDWS
I've never had luck with the TAA brass...

Because I have a lot of time on my hands (and cheap too), I'm working my way through the NATO brass, running each one through the neck turner. At least I'll have some very concentric necks when I'm done. I'll see how it turns out when I fireform them. It has resized easier than the WCC brass, which I've never been overly fond of. But I'll make sure I order LC brass from here on. It's always been good stuff.
0
OldVet

Avatar / Picture

Member
Registered:
Posts: 31
Reply with quote  #22 
Quote:
Originally Posted by MDWS
I've never had luck with the TAA brass...

What about the TAA brass didn't work. Just wondering what I should watch for. So far, other than requiring neck turning, it seems doable.
0
Previous Topic | Next Topic
Print
Reply

Quick Navigation:

Easily create a Forum Website with Website Toolbox.