Home Forums Reloading Big Game Rifles 6.5 creedmoor hodgdon vs Nosler load data disparity

Guys; I was using the max data for Nosler 100g partition Nosler published data and it blew the magazine out of my m1a, Varget powder

I shared my load and was told it was way high, look at the hodgdon data

I did, the powder loads are way than the Nosler data

What’s the deal?

What was your charge of Varget for your M1A?

I do a lot of 260 Remington loads with 100 grain bullets, but that is in a bolt action....
Creedmoor isn't much different....

helped a friend years ago do load data for the 260 in an M1A.... he was using 4064 that I was using with 100 grain bullet..

worked in his M1A with no issues.. and was very accurate...

The deal is you apparently loaded up book max - and went out and shot it - rather than working up to a load.

Ever heard of variances in powder burn rate, case capacity, etc?

This is what is happening. Got a lot of newbies at the range, trying their hand at loading their own because they can't find ammo in the stores. They not only risk their own lives, but also those around them..

Yup, every loading manual that exists says to work up to max loads and stop if you see any signs of pressure, even if you're just changing one component- bullets, primers, brass, or powder. This is what happens when you refuse to read the manual and don't follow safe loading procedures... lucky someone didn't get hurt...

Bob

Looking at the online resources for both, Nosler max for a 100gr bullet backed with Varget is 42gr, and Hodgdon max is 43gr.
I wouldn't call 1 grain "way higher".

We need you to be specific. What was your exact load, including brass, primer, seating depth etc.

Did you work up, or completely ignore everything in every loading manual ever published and start with a max load?

Have you loaded for this gun before, or used this lot of powder with other rifles, and were the results as expected?

Are you 100% positive you grabbed the correct power and bullets?
Did you grab the H4198, or a 120gr bullet, or perhaps a 7mm bullet?

On another front, do you know the history of this brass?
A case head separation can do bad things.

Blowing the magazine out the bottom takes a lot of pressure. Barring any of the events I mentioned above, I'd expect it to take a lot of powder, and a highly compressed load to do what you described.

OK, very little supporting data in the OP so I had to go look. I will stipulate I know nothing about an M1A and what its pressure constraints are.
Here are the max 6.5 Creedmoor data listed online at the two referenced company's sites:
- Hodgden does not list a Varget load for the 100 partition, but does list the 100 BT. 40.5 grains for 3122 FPS at 60.3K PSI - fairy low pressure
- Nosler lists generic data for all their 100 grain bullets - 42.0 grains Varget for 3165 FPS (no pressure listed)
- Both companies used 24" barrels

My opinion is 1.5 grains is not a big difference, particularly since the velocities achieved were only 40 FPS apart, and the one referenced pressure was well below the CIP max.

As I said, I've no idea what an M1A can handle, but I would expect it will do just fine with factory .308, which is less than the 60.3K Hodgden listed.
I agree with the others who said (of course!) you always start low and work up.
I would want to know more about how an M1A works to be sure it was the cartridge that "blew the magazine out." Doesn't look to me that the data would suggest it was the load's fault.
What else happened to the rifle?

Cheers,
Rex

Antelope_sniper, looks like we were typing at the same time, but I found different Hodgden data than you did.

Cheers,
Rex

Opps,
I posted for the 95gr NBT.
Regardless, even if he used the 95gr NBT data, I see no way he blow the mag out the gun unless something else was dreadfully wrong.

Maybe all is good, and the OP just didn’t fully insert his mag. 🤣

That would be just too simple....