Sako 6PPC Factory Chamber Specs.

There's some fired Norma 6PPC brass for sale on Gunbroker, and the seller has turned the necks to .009", indicating that this gives a loaded round dimension of .261". He then states this brass will fit the Sako factory rifles and others so chambered, and is not for BR work. I was under the impression that Sako chambered the 6PPC with a neck dimension of .272", and would think this brass too thin. Anybody know for sure what Sako 6PPC chamber specs are? Thanks!

 

"Too thin" necks will work just fine in a rifle's chamber, however, thin-necked brass may not last as long due to the extra work-hardening it receives when fired and resized. Some will argue whether it will provide less accuracy than brass which is a closer fit for the chamber neck.

I don't have a reference immediately at hand for the 6PPC USA of the Sako chambers, but SAAMI standards for other 6mm rounds like 6mm Remington and .243 Winchester show a chamber neck diameter of .276" (which would nominally use a cartridge with a neck of about .272").

 

The whole purpose of owning a Sako 6PPC is to benefit from it's accuracy potential. The brass you reference will work in your Sako PPC USA chamber but it's not likely to give the best accuracy, so why bother with it. Just do a search online for the SAAMI specs for the Sako 6mm PPC USA chamber to get all the dimensions. The better the neck fit, the better the accuracy!! Just my two cents.

 

Yep, accuracy is the whole point. However, finding SAAMI specs on the PPC cartridges is not easy! I assume they exist, but I don't see them on the website at saami.org even though there are dozens of newer cartridges listed. I guess the best thing to do would be to make a chamber cast.

 

https://en.wikipedia.org/wiki/6mm_PPC

A little more info if you haven't seen this yet.

https://web.archive.org/web/2007092...ta(Rifle)/243Cal(6.17mm)/6mm PPC page 202.pdf

 

CIP specs (which is the Euro version of SAAMI) shows a loaded cartridge neck diameter of .268" for the USA version making the neck wall thickness .0125". This would translate to a .272" chamber neck. The USA cartridge also has a fatter diameter body near the web to discourage trying to chamber it in a tight necked 6mm PPC bench rest chamber. That Norma brass could very well have the smaller body diameter which would also make for a sloppy fit. Using Sako brass or brass made to the USA chamber specs is your best option. The link CVCOBRA1 refers to is for the 6MM PPC round NOT the Sako 6mm PPC USA, so that info does NOT apply to your chamber. Good luck!

 

Well, $$$$ it, I tried.

 

Thanks guys, I appreciate the help!

 

https://www.6mmbr.com/6ppc.html

A good read here. I think a lot of what the OP is looking for depends if he is shooting matches and wants to shoot in the "one's" or if he just wants a very accurate varmint rig to 300 yards. Not sure the date on the article but they mention IMR 8208 "Thunderbird" the go to powder. Then it became the unicorn, of course now it back. Make sure you read all the way down to the "No Turn" option. If you are picking up a used PPC you are more than likely not going to shoot a match with it.

 

I like to do some informal benchrest shooting with my HB Sako, and want to use it for varmints too. Shooting in the "ones" would be amazing, but not likely to happen with the well used rifle I have. (And with my inability to read the wind very well)
A very good article, thanks!

 

@RifleNutPPC
Did you ever get the #'s on your chamber. Reason I ask is I am in the process of purchasing one and would like to know the chamber #'s as well. TKS

 

The 6mmPPC was introduced in 1975 & soon dominated certain benchrest classes, but it never had a standardize OAL, neck diameter, or throat specs because the benchrest shooters would have their chambers cut for the bullet they wanted to use & neck diameter of their preference. So if the rifle you are purchasing is one of the early custom ones it would be impossible to know the #'s on that chamber without doing a chamber casting. About 10 years later Sako standardize the cartridge calling it the 6 PPC-USA. CIP & SAAMI accepted it & provided the dimension specs for it so all rifles & ammo would be compatible. The USA version may or may not chamber properly in an early custom BR rifle & vice versa. The drawings & specs for the USA version are available on-line by doing a simple search. It's best suited to single shot rifles as it's short length & sharp shoulder can cause feeding issues from a magazine.

 

I have a number of the Sako factory rifles in 6PPC, and use the Sako and Norma brass with no problems.

 

The rifle I am referring to is a Sako single shot 6mm PPC USA. Brass is hard to find so I was wondering when I form some what the chamber neck specs were so I could determine if I would need to neck turn or not.

 

Gotcha. I didn't realize it's so hard to find factory brass. Sorry, I never did the chamber cast, so don't know the exact dimensions of any of my chambers. I've also never fire formed any brass, but I'm sure someone on the forum has had experience with same.

 

Would you by chance have a fired case on hand. If yes could you measure the fired neck diameter (outside) and let me know what it is. This would give me an idea of the dimension. TKS

 

Read post #6 of this thread. Also, I just Googled "6 PPC brass for sale in Canada" & came up with multiple sites that had brass & loaded ammo in stock.

 

Sure thing. I just miked half a dozen fired Sako cases. They measure right at .270", plus or minus half a thousand.

 

A few links would be great as I can't find any.

 

Thank you. This would lead me to believe the chamber neck would be .271-.272. Loaded round would need to be somewhere around .268-.269