Some .308 ammo questions

[realmswalker]

I just received some ammo from a trusted friend. some of the .308 ammo was loaded with 175 grain molly coated sierra match kings. The overall length is 2.898. My speer book says max cart length should be 2.810. They chamber fine in my rifle.

Is there any negatives or dangers to having the COAL this long, or should I reaseat them to 2.810?

Also I received 100 rounds of brand new hornady match .308 brass. I have never had brand new brass before. Do I need to run this brass through my sizing die?

Or can I just chamfer, prime and load?

Thank you for your help.

 

[RavenVT100]

Two questions:

1. Have you measured the length of the freebore of your rifle?

2. These are your friend's reloads, correct? By your first statement, I am assuming that they are.

I have never had brand new brass before. Do I need to run this brass through my sizing die?

Measure the headspace of the brass with a gauge (RCBS precision mic, for instance) to see if they're sized correctly. If not, resize them.

 

[realmswalker]

How do I measure the freebore of my rifle?

I don't have a precision mic. The only measuring tool I have is a set of electronic calipers.

Yes they are my friends reloads. 42.8 grains of 4064

 

[bragood]

I would reset them if I were only going to shoot them (im assuming you only have a few). Or you could play with them if they are a mild load?

 

[realmswalker]

42.8 is pretty close to the max, I will probably just reset them to 2.800

 

[steve4102]

This is what Accurate Powder says about OAL.

SPECIAL NOTE ON CARTRIDGE OVERALL LENGTH “COL”
It is important to note that the SAAMI “COL” values are for the firearms and ammunition manufacturers industry and must
be seen as a guideline only.
The individual reloader is free to adjust this dimension to suit their particular firearm-component-weapon combination.
This parameter is determined by various dimensions such as 1) magazine length (space), 2) freebore-lead dimensions of
the barrel, 3) ogive or profile of the projectile and 4) position of cannelure or crimp groove.

New brass needs to be prepped. They have been bouncing around in bags or boxes and the necks may not be nice and round any longer. Run them through a neck die to straighten the necks. If you do not have a neck die, FL size them. Then you need to check length, deburr the outside and chamfer the inside of the necks. I always uniform the primer pockets as well.

 

[Grumulkin]

Resetting the bullets is NOT necessary unless the cartridges are so long that the bullets are engaging the lands. Unless they're engaging the lands, seating the bullets deeper will RAISE pressure and not lower it.

As for prepping new brass, why??? Do you really think that, for instance, Remington, takes their new brass and preps it before loading it into cartridges? The only new brass prepping I ever do is to chamfer the mouths if I'm going to be seating other than boat tailed bullets or make a dented mouth round if necessary.

 

[243winxb]

I just received some ammo from a trusted friend. some of the .308 ammo was loaded with 175 grain molly coated sierra match kings. The overall length is 2.898. My speer book says max cart length should be 2.810. They chamber fine in my rifle.

If they fit the magazing and chamber, then they are fine to shoot. The only danger is your trusted friend. The ammo should be marked as to what he loaded. Compare his powder type and how many grains he loaded to reloading data, you might not want to shoot them in your gun if the ammo is loaded to maximum.

Also I received 100 rounds of brand new hornady match .308 brass. I have never had brand new brass before. Do I need to run this brass through my sizing die?

Try a few in your chamber, if they go in ok, i just make sure the mouth is round by bumping the case mouth with the expander ball, then chamfer them and load.

 

[realmswalker]

Thank you for the advice, I appreciate it.

 

[30Cal]

How do I measure the freebore of my rifle?

Stuff one into the chamber with your thumb. If it falls out from gravity alone, it's not touching the lands.

 

[Bowfishrp]

I always resize my new brass....better to be safe. Most of the new Winchester brass that I have needs to be resized anyway. They are normally close but will be better for overall accuracy.

 

[243winxb]

Molly Coated Bullets

If you don't always use Molly Coated Bullets, switching back from coated to uncoated can possibly have an effect on your accuracy. You can read lots , pro and con on the subject. Some say Molly can be very hard to get out of a barrel. I have not used molly myself. But i do know in 22lr, the different coatings/lubes can have an effect on accuracy when switching ammo brands. I would think a good cleaning is in order when going for one to the other.