7.62 Lake City Brass and IMR 4064

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It wasn't, couple guys claimed success with it here on the interwebs, buts its really out of place. I could tell within the first couple shots that it was no bueno.

You know, I might try that, load up another pressure ladder with R10x for the LC brass. Why not? I actually really like R10x, not the cleanest either, but seems really consistent. I don't have a chrony though, thats just from my feels.
 
So, went to the range this morning... thought I'd share results as quick as possible so everybody who helped chimed in would know.

15degrees F, no wind, very low humidity. 10%ish
Mixed LC brass
Ruger Gunsite Scout Rifle 308 Win
IMR4064 powder. 8 rounds
Speer 150 gr hot cor SP
Charge weights: 42, 42.5, 43, 43.5, 44, 44.5, 45c, 45.5c

Most of the primers looked flat, but not absolutely flattened or cratered. Most likely my gorilla forearms on the press. The bolt started to get stiff about 44.5, and was the same for 45, and 45.5.

Same data for R10x except charge weights.
.5 grn increments 34.5-39. None compressed. Primers looked A ok. No sticky bolt. Similar POI

Like I said before, I don't have a chrony, and these were just to find pressure because of the cases. The only noticeable difference between the two powders was recoil. IMR4064 was DEFINITELY stiffer. And the Rx10 cases were sooted up more.

So... I am going to start load development with this bullet and IMR4064. Probably gonna start with 42.5 grains and go either .4 or .3 grain increments to 44.5.

That's what I got for now :)
 
Ha thanks, it was cold this morning :eek:. Nice sunrise and all the benches were in the shade until it didn't matter.
 
I started tuning last February /March for my long range season, it was definitely cold and snowing here in NW Montana that time of year , especially cold in the reloading shack.
 
Haha ya. I paid extree for better insulation in the garage. I got a plan for a smaller room if I ever build my barn. So much easier to heat a small space.
 
Was going over some load data for 308 and IMR 4064......and it appears a lot of load data is way out of whack. As noted on a previous post, a "full" case of 4064 for me is 43 grains. Any more, and it starts to compress. That is measured after I size a case, drill out the primer pocket to powder can be poured in from the head....then seat a bullet to the COL listed for the bullet (Hornaday source). Then fill the case to the base of primer pocket dump it out and weigh it.

If I fill an empty, but sized case to the rim....then scrim it off and weigh the contents....it's 47 grains.

Load data from Hodgdon and others has a START? load of 43 grains, and MAX load of 47 grains. I don't know much about compressing loads, but can't imagine you could get a bullet to seat properly with that much powder. Hornaday load data is way less.......as in 3 to 4 grains lower.....start and finish.

Again, numbers seem out of whack. BTW, a Lee dipper with my powder sample is exactly where it should be for IMR 4064 from the Lee dipper charts, so does not seem to be a lot sample issue.
 
with stick powders, you can make adjustments to the way you drop your powder to get more in the case. I find a straw under one funnel and dropping the powder so it swirls into a second funnel over the cartridge helps to get more powder in the case without making it a compressed load... just making the powder more organized as it fills the case. Still, I never go over the book max on a listed powder. I also sort cases by weight.

This might help get the charge you want into the case.
 
Both. Tried it with LC and new Starline, and both gave me similar results. Full to the rim was around 47 grains.

Two sources have max loads of 47.7c grains of IMR 4064 under 150 grain bullets. There would be no room at the Inn for a bullet.

Hornady load data has it topping out at a max of 44.9 grains......which would be doable. Again, the others with a just seem out of whack. Their start loads are close to where Hornady finishes up.
 
Howa, this is one of the reasons why I brought the question up. Seemed like load data is way too high, and given that LC brass is thicker, problems could? may? arise? The one that got me was Speer's data. I think max is 47 for IMI cases and if they are nato spec (I could be totally wrong, I don't have any, so I don't know, but I read somewhere IMI is Israeli Military), 47 would be right at the mouth or over flowing???????????????

I was more interested in the "finding the top end of pressure" procedure for LC brass thats quick and easy. But the question you articulated is still fresh on my mind.
 
It was not only Speer, but I found the same in the Hodgdon and Lee data (same thing as Lee just republished powder company data). Worse, my Lyman 50th shows 48 grains. On a hunch, I went back and looked at the same load in the Lyman 45th from 50 years ago.......and it too showed 48 grains. Even more curious.....it showed 48 grains of IMR 4064 was their most accurate load? Not sure how you could ever get more powder under a bullet than the case will hold empty. Perhaps if you run those Lincoln logs through a chipper shredder to turn them into sawdust? And again, it occurred to me my lot may have been cooked up different.....so I pulled out a Lee dipper and weighed that against what the Lee manual said it should be, and got the exact same amount.

Then there is the Hornady manual. It tops out a max load at 44.9 grains for a 150 grain bullet over IMR 4064.......an amount you would actually have a chance of fitting a bullet over and compressing. Just hard to believe such an inconsistency between book values and reality could persist in all these load data sources for so long.

But also confirms that the notion of starting low and working up is always a good idea. If for no other reason than situations like this are evidence that the data is not to be trusted.

But as for the loads the OP listed in post #52 above, that is exactly where I'm headed too. My max will end up around 44.5 to 45.0 grains, both of which will be compressed loads. If those don't work as for decent accuracy with factory level velocities, the IMR 4064 will get used for something else.
 
Howa 9700 said:
It was not only Speer, but I found the same in the Hodgdon and Lee data (same thing as Lee just republished powder company data). Worse, my Lyman 50th shows 48 grains. On a hunch, I went back and looked at the same load in the Lyman 45th from 50 years ago.......and it too showed 48 grains. Even more curious.....it showed 48 grains of IMR 4064 was their most accurate load?

If those don't work as for decent accuracy with factory level velocities, the IMR 4064 will get used for something else.
Click to expand...

^^^ I too noticed the inconsistencies in the other manuals (and the lyman, I don't own a Hornady.. Been meaning to pick one up for a few years). I brought up the Speer only for the reason that it uses military brass for the 308 data. I'm glad everybody has chimed in, because it's such a popular powder in 308 and thought maybe I was missing something, which has happened before and will happen again.
 
IIRC Lyman 50 shows IMR4064 as most accurate with a 150 grain hunting bullet in 30-06. Been meaning to try it just cuz.
 
One of my favorite 308 bolt gun target loads is a 155 OTM W/ 45.0 grs. of IMR 40464. Very accurate and gets out to 1000 yds. with no problem.
 
So.... just wanted to reply because everybody was super helpful. The rifle likes 43.8 grains IMR4064 with 150 grn Speer HCSP

Meow... another question. And something I've always wondered about. That charge is right at 100% full at SAAMI COAL- 2.700. No noticeable compression in my guestimation. I measured that I am around 85 thou off the lands with that particular bullet. I am wanting to use the mag still but I do have room to bring the COAL out further and want to test it, opening case capacity, but not much.

Will this raise pressure or lower it?
 
To clarify, 2.700 isn't loaded to SAMMI specs. SAMMI spec is 2.810....the difference being a full 1/10th of an inch. The 2.700 is Speer's recommended OAL that gets to the desired seating depth of that bullet. The 150 Speer Hot Cor, compared to most others, is a short, stubby bullet with no cannelure, which according to many, is a good accurate bullet for hunting. But seating depth of 2.700 works.....so much for the need to seat bullets out to the lands, as there would be a pretty big jump seating this bullet to that depth.

As for pressure changes, I'm not qualified to say, but my understanding of the theory suggests if it changes at all, seating further out would reduce pressure slightly.

I'm paying attention, as I'm following in your wake. My only way of monitoring things is to run my test loads over a chronograph. An accurate load close to factory velocity is what I'm looking for. Will be curious to see where that falls out.
 
TheClasonater said:
Will this raise pressure or lower it?
Click to expand...

Generally speaking, lengthening the OAL will lower pressures...until you engage the rifling with the bullet. There is more to it than that, however... by seating the bullet shallower, you are losing that amount of neck tension on the bullet as well.

My thought is... if you are getting good performance from the book seating depth, I'd call it a day; there is a reason Speer published that specific seating depth with that bullet.
 
Howa 9700 said:
To clarify, 2.700 isn't loaded to SAMMI specs. SAMMI spec is 2.810....the difference being a full 1/10th of an inch. The 2.700 is Speer's recommended OAL that gets to the desired seating depth of that bullet.
Click to expand...

You are totally correct, I misspoke. Dont know why I did that.

Charlie98 said:
My thought is... if you are getting good performance from the book seating depth, I'd call it a day; there is a reason Speer published that specific seating depth with that bullet.
Click to expand...

You are also correct, but I thought hey, why not give this a try. I've enjoyed it thus far for this rifle and wanted to go another step. Pressure was the first question I had way at the beginning so this question would be the next step
 
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