308 Win Chamber Variances

[TyRifle1]

I have a question that maybe you folks could answer. I have plans on building up a custom 308 win. Should I chamber it with factory 308 saami specs or should I go to a match chambering? If I use a match chambering will I have trouble using multiple types of factory match rounds? I do reload but still want the ability to use factory ammo... at times. Thanks in advance.

 

[Guest]

Well welcome to the board....

you are going to want to e-mail Chris Matthews. He's built probobly 150, 308's over the past 2 years. But ask him about the chamber and neck he cut for me... shoot factory Black Hill's into the 3's or better , it shoots my handloads into .2's consistiently.

He's done this for several people... and each 308 shoots the same... probobly better now that he's getting his barrels from Tim North( Broughton Barrels)

his e-mail is [email protected]

 

[Mike in Texas]

Pac Nor did a pair of 308's for me recently.
1 barrel is absolute min spec with a .337 neck. Very tight.
the other barrel is nothing more than a factory remington chamber they call their "sniper" reamer. Max dimension with a long throat.

There is no accuracy difference in the barrels at close or far distance. The loose chamber is alot more user friendly.
Both barrels shoot in the very low 0.2 range for 5 shot groups.

I'd go big and save the hassle. A concentric chamber of any dimension is a huge improvement over a factory cut chamber.

 

[Guest]

yeah ty, maybe you should listen to your friends, haha /ubbthreads/images/graemlins/grin.gif

 

[TyRifle1]

Thank you all for the speedy replies. I will contact Chris about chambering, but I also agree with Hoodcounty that any concentric chambering is better than a factory one.

 

[chris matthews]

I'll go ahead and chime in here....
I have 2 reamers that I use for the 308 Win.
1. PTG 308 Bisley Match with a 0.339 neck- used on Ric's rifle and my personal 308- You can use Winchester brass or ammo, Black Hills ammo and Lapua brass or ammo without neck turning. Throated for the 175 MK.
2. Is the same thing but with a 0.342 neck and it will take ANYTHING including the super thick Federal brass.

Most 308 factory ammo is about 0.339 or 0.340 in diameter at the neck on a loaded round- you can see that the 342 nk still gives plenty of room but keeps you from over working the brass. 0.346" is SAAMI spec for the neck- works the hell out of the brass and can decrease the number of firings before annealing is needed.

Both reamers are "Match" reamers, meaning they are SAAMI min. spec in the body....

But like was mentioned a good straight chamber is better....

 

[James Jones]

Chris with the reamer setup for throating the 175gr MK , is it so deep that one can't reach the lands with a 150gr bullet?
is their any way that someone could have a chamber setup for shooting the lighter bullets like 155 and 168 say for a hunting rifle that isin't gonna be shot past 500yds?

 

[chris matthews]

I can use a 95 Palma reamer- throated for the 155s....

 

[TyRifle1]

Thanks Chris,
I haven't had the chance to email you yet but now I don't have to. I think .342" is the way to go for me.