Order of steps in reloading?

[Trent]

Greg; when a cartridge is fired, the brass case expands to fill the chamber and "STICKS" (quite solidly). When the pressure drops the brass case springs back a little.

If the case is lubed, you have effectively made a "proof load" where the case can NOT stick to the chamber while pressure is maxed out, and you load up the lugs and bolt face with *all* of the pressure the round is generating.

If my recollection is correct, the British used to slather some sort of oil/grease (molasses?) on loads to proof Enfield rifles. Or maybe they were the "blue pill" proof loaders that used 150% overpressure loads to test rifles. Can't remember. Someone did.

Maybe RC Model would know, he probably helped them design the tests back in 1890.

 

[Greg Mercurio]

Trent: Thanks for your explanation, but I remain unconvinced that the surface friction of clean brass is enough to overcome the longitudinal forces of a bullet being accelerated from zero to +2k fps in a few milliseconds, with chamber pressures in the 50K range.

In the firing sequence, the firing pin forces the case forward to take up any headspace, Newton takes over and does that equal and opposite thing, pushing the case backwards, at the same time the case is expanding. Not sure the rather tiny surface area of the brass case is capable of "gripping" the chamber walls with sufficient friction to overcome the forces being generated.

If it was, I think locking lugs in general would be rather wimpy and
unnecessary? :banghead:

Did some more digging around and found this nifty little treatise on the subject. In the real world with real-world chambers and real-world brass, the addition of a bit of remnant lube should not have any measureable affect on bolt thrust.

http://www.varmintal.com/a243z.htm

 

[Trent]

Greg;

I have to disagree with you, via first hand observations of the 5.7x28mm in blowback firearms (PS90, FiveSeven).

If you tumble the brass and strip the special dry film lubricant off of it, your cases WILL NOT leave the chamber, and the rear of the case can (and sometimes will) blow out due to stretching to the point of rupture.

The lubricant coating on those cases allows it to slip out of the chamber under pressure.

 

[Rushthezeppelin]

HAHA! I prefer a nice room temperature glass of Macallan 18 year.

Room temp Glenlivet or Speyburn for me And I as well would never waste it on cleaning ammo.

As to the cleaning lube after sizing it also depends on the lube. I know One Shot can contaminate primers and powder but other lubes like Lee Sizing Lube will not. Still good idea to have the finished ammo clean because of the case slamming into the bolt obviously.

 

[Shinbone]

I think this question fits here...do you lube rifle brass necks on the inside to help with the expander ball moving in and out? If so, what lube do you use?
Thanks.

 

[Trent]

Shinbone - I do this on certain rifles which I have tight neck tension set on (8x57 for semi auto use, etc).

I do one of two things depending on mood or cartridge. I either tap the mouth of the case in a 1/4" deep tray of ground mica, or I use a q-tip very lightly coated with RCBS case lube around the inside of the mouth of the case. (I actually just roll the q-tip on the lube pad that's soaked with the lube, so there's just a very thin film).

The ground mica is my preferred method because I don't have to clean the lube off. If you do lube the inside of the case neck with case lube, it needs to be cleaned off before you seat bullets. It will work against you on seating tension, having lube in there... could cause setback on chambering in semi-autos, cause powder to stick & bridge, etc.

 

[cfullgraf]

And back to OP -
1. Tumble
2. Lube
3. deprime/resize
4. trim if necessary
5. Chamfer
6. Tumble a 2nd time. - Is it necessary? no, but I'd rather not have the lube near the powder or primers.
Probably not important, but why take the chance?

This pretty much what I do with rifle cases.

The first tumbling is to get rid of range grime, the second is to get rid of the lubricant.

Besides my preference to keep the lubricant away from the powder and primers, I do not like sticky, oily fingers when I am handling primers and powder.

 

[Trailduster79]

For pistol rounds my process is very simple. Kinda like Robb's

Clean
Size/Deprime
Expand
Load
Shoot
Repeat

Rifle adds the lube step before sizing and wipe cases step after sizing

Obviously trim is included if needed.

 

[kutter]

Trent I am confused, are you saying that a cartridge that creates approximately 50K psi requires case lube to be extracted from the chamber when a very similar round the 5.56x45 which operates up to 62K psi does not? is there something special about the 5.7x28?

 

[leefan]

Use a separate crimping die.

 

[Andrew Leigh]

Rifle loads. I only shoot batches of known headstamp so there is no need to sort.

1. Deprime with dedicated depriming tool.
2. Wipe case necks clean of the blowback with Laquer Thinners as the Ultrasonical cleaner does not always remove this residue (don't own a tumbler yet). Also annealing may be required.
3. Check my "Case Preperation Log" and determine if annealling is required. If so anneal.
4. Lube
5. Either F/L or Neck Size.
6. Trim to length.
7. Debur inner and outer edges of case mouth.
8. Ultrasonically clean again.
9. Update my "Case Preperation Log" with the new number of how many times the cases have been loaded, what sizing method was used and what die set.
10 store.

 

[stavman11]

well My system almost the same as most

1 Grab Dirty Brass... Tumble in Corn Cobb with a Dash of Polisher for seasoning..
2 Put about 100-200 in a box.. Spray with my Home Brew Lanolin Lube.. shake box... one more Spray of lube
3 Tumble again for maybe 45min to 1hr
4 Size and De-prime all at once
4a Trim Primer Pocket on New Crimped Brass
5 Check a Good amount for Length (usually no need ta Trim too often)
6 Inside Chammfer all
7 Hand Prime
8 Run through Lee pro Progressive
9 Load into Mags at range
10 Shoot the Custom Loaded Ammo
11 Pick up Brass off of Ground
12 Rinse and repeat as needed

 

[Trent]

Trent I am confused, are you saying that a cartridge that creates approximately 50K psi requires case lube to be extracted from the chamber when a very similar round the 5.56x45 which operates up to 62K psi does not? is there something special about the 5.7x28?

The 5.7 action is blowback, not gas operated. It won't "blow back" properly if it isn't lubed; the brass will be under too much pressure to move backwards. Instead, the rear of the case will stretch and pop like a balloon.

Another method to easing case extraction on blow-back can be found on the G3-H&K91-etc platform (fluted chambers).

There are also a number of old machineguns which required oilers for the same reason, to allow brass to extract under pressure.

The 5.56x45 / 223 action is gas operated. The direct gas impingement causes the bolt to begin rearward movement after the bullet passes the gas port; by the time the bolt travels rearward enough to turn the bolt and unlock the chamber, the bullet is out of the muzzle, gas pressure has dropped off and the round can be extracted. If the bolt tries to unlock before the bullet leaves the barrel and the gas pressure has not dropped, it will cause a really bad failure.

You can snap an AR15 bolt in half if your port pressure is off for the port location in the barrel. E.g. 16" barrel with pistol length gas system firing a slow burning powder keeps the case expanded; it has high back pressure and wall pressure. The bolt can't twist to unlock because of the sidewall pressure of the case, and can cause the bolt carrier to snap in two, where it is thinnest. (I've got such a broken bolt here, if you want pictures to illustrate...)