Nosler gilded jackets

[longguner]

The other day I loaded up some PT for my Remington 760 .308 winchester and had excess pressure at the minimum charge by seeing the primers flattening. The recoil began to increase at the second increment so I stopped and head back home.

I know now to try other powders and just shoot start loads to see how it goes before loading up.....

A friend suggested to load at the range. Any other advice would be helpful. Thanks

 

[OU812]

More info would be very helpful. Bullet weight, powder used, primer used..ect

 

[longguner]

180 PT H BLC2 CCI 200

 

[AzDak42]

180 PT H BLC2 CCI 200

What charge?

 

[longguner]

42 to 46 grains...

 

[elkeater2]

Curious why the original subject? Do you think the jacket material for the PT may be a factor in the apparent pressure issue? Have you shot factory 180 gr. ammunition in the 760? The 180's will produce more felt recoil than the lighter bullets, especially if they are moving at close to factory velocity. Primers will flatten for reasons other than pressure, sometimes in lower power 'starting' loads. Not questioning your wisdom in packing up, not hardly. CCI 200's have a fairly tough cup, but you might try a different primer if you have some.

Keep posting, someone will have the answers for you!
EE2

 

[longguner]

EE2

I've read from other load manuals that some bullet jackets are harder than others.

Saying that, I've shot Sierras 180's and considerably less recoil is felt.

I've never had primers flatten with lower pressure starting loads.

So CCI's burn hotter? Which ones don't burn as hot?

 

[JD338]

PT's normally run at higher pressures than standard cup and core bullets.

JD338

 

[longguner]

JD....

Generally what powders keep the pressure down?

I always thought slower burning but Hodgdons told me the opposite... faster burning create less pressure.

 

[Ridgerunner665]

Hodgdons musta misunderstood the question...

The peak pressure with slow vs. fast powders is often the same...the difference is in how fast they reach peak pressure. Slower powders burn slower so the reach the peak slower...and in doing so they push the bullet for a longer period of time...thats why slow powders generally give higher velocity.

You do not want to keep pressures down, per se...you just want to keep them below 62,000 psi (SAAMI peak pressure for the 308)...

Flattened primers...I don't even look at primers anymore, they lie...especially in high pressure rounds such as 270 Win...lost of things can make primers look wrong (bolt face, firing pin hole, low pressure, etc.)

I've never used BLC2 myself (don't much care for ball powders)...all I'm saying is primers are the WORST way to attempt to judge pressure.

If you have any Varget or Reloder 15....about 44 grains should be about right for a 180, but start at 42. (45 is MAX for both)

 

[longguner]

Funny you mentioned VARGET.... I have a load with Sierras 165 GK HPBT at 44 grains.

There was still a slight radius along with flattened primers......

The pockets didn't open open up to the point of a new primer being loose when seated.

Also the case head measured in spec... so it's all good.

Um duh... if I looked at the pressures in the load book... I would see, the peak pressures.

I only used blc2 because it's supposedly THE powder for the .308

I'm running out of Varget, but have 748.. which I'm gonna try next.

Thanks for pointed out about powders.

 

[Guy Miner]

Did a lot of match shooting up until a few years ago. Up and down the line, almost everyone with a .308 was loading with Varget. A few with IMR4064 (particularly guys who'd been competing with a .308 for decades) and some with RE-15, or H4895.

BLC2 and H380 can work great - but don't seem nearly as popular. I'd just buy an 8 lb jug of Varget and enjoy consistent accuracy and good velocity. In fact, that's what I do every now and again! :grin:

 

[longguner]

Thanks Guy....

IMR 4064 and 4895, Varget, I see alot of thumbs up.

Since I'll only use it hunting, another pound of Varget will do.

I have IMR 4895 in 8 pounds for the M-1.

 

[Oldtrader3]

I load only for a .30-06, bolt action, Model 70, so pressures and pressure curves are going to be a little different. However, I normally use IMR 4350, 57.5 grs with the Nosler Partition and have been using this load since 1965.

The PT bullet is a compound bullet design with an impact extruded jacket metal Partition located precisely under the tangent point of the bullet ogive and shank. This design does affect chamber pressure because the Partition prevents bullet sizing deformation somewhat. This feature does tend to spike pressures a little faster and higher than lead core and cup bullets without the Partition.

You should be able to use 748, without any issues. I have used 748 in .30-06 loads for 165 and 180 Partition bullets and never had any problems. I do not remember my precise load as it has been awhile since I loaded 748 for .30-06 and my load was for .30-06 bolt action. Good luck with Varget and 748, both should give you good results.

 

[elkeater2]

I didn't want to imply that CCI primers are hotter or a potential source of increased pressure at all. What I was trying to say was that the actual metallurgy of the primer cup does vary from brand to brand and even within regular vs. mag in the same brand. These variations can give you fits if you are a primer reader and trying to reach conclusions about pressure.
The AR .223 crowd recognizes this as they have issues with pierced and cratered primers with certain loads and rifles. It has long been known that the CCI450 small rifle magnum primer has a tougher cup than the 400. So the 400's look cratered and abnormal, while the 450's look fine - just opposite of what you'd think if you were looking for increased pressure with the same load.

Another point - some of us (me included! :mrgreen: ) have been guilty of not really getting case exteriors clean of lubricant really well. If you load and shoot a batch this way, the cartridges react differently in the chamber and primers will look different. I have been pretty careful about this lately. Then another discovery - if you get the light just right shining in the chamber, the chamber walls have a nice pressure driven discolored coating from these lubed cases. Most of us are pretty good about bore cleaning but there isn't much mention of chamber cleaning. Again, this is slight but noticeable and likely a factor in some way.
Let us know how it goes!
EE2

 

[Oldtrader3]

That comment on lubricant in necks is why I have, in every case possible, converted my sizing dies to Forster carbide neck sizer buttons. These buttons are very smooth and non sticky in use, when sizing necks and are very well made and dimensionally controlled, plus, I do not need to lubricate necks which saves me having to clean or tumble cases.

 

[elkeater2]

Neck sizing is great, but I don't think it works very well in Remington 760's like the OP has...

 

[buckfever]

I use 48gr of imr 4350 with 180gr pts with great accuracy

 

[longguner]

I didn't want to imply that CCI primers are hotter or a potential source of increased pressure at all. What I was trying to say was that the actual metallurgy of the primer cup does vary from brand to brand and even within regular vs. mag in the same brand. These variations can give you fits if you are a primer reader and trying to reach conclusions about pressure.
The AR .223 crowd recognizes this as they have issues with pierced and cratered primers with certain loads and rifles. It has long been known that the CCI450 small rifle magnum primer has a tougher cup than the 400. So the 400's look cratered and abnormal, while the 450's look fine - just opposite of what you'd think if you were looking for increased pressure with the same load.

Another point - some of us (me included! :mrgreen: ) have been guilty of not really getting case exteriors clean of lubricant really well. If you load and shoot a batch this way, the cartridges react differently in the chamber and primers will look different. I have been pretty careful about this lately. Then another discovery - if you get the light just right shining in the chamber, the chamber walls have a nice pressure driven discolored coating from these lubed cases. Most of us are pretty good about bore cleaning but there isn't much mention of chamber cleaning. Again, this is slight but noticeable and likely a factor in some way.
Let us know how it goes!
EE2

Good points EE2...

I tumble my brass after lube and sizing.....

And as far as flattening primers ..... as long as the pockets don't open up I'm good and the case head stays in spec... I keep goin..

I still see a slight radius on the primer I know I'm good.

 

[Antelope_Sniper]

The CCI 200 is a cold primer. I would not suspect it as a source of excess pressure.
In addition CCI's are a hard primer. They will blow before they will pierce.
I've used BLC2 in the 308 with success. It likes either a match, or a magnum primer. I've had good luck with the BR-2's.

The US military ball loads for the .308 are essentially blc-2 and CCI 250 Primers.