I have a pretty good load for my .300 Win Mag that I use for some long range target shooting. I developed the load with Winchester brass that I carefully prepped with most every step you can think of except weight sorting.

I decided to buy some good brass; Nosler.

Do you think that I will have to rework the load since I am changing the brass or will it be just fine?

Rule of thumb is to reduce powder by 5% or so any time you change any component then start working back up. It might be helpful to see how close the Nosler brass is to the capacity of the Win. Of course if your existing load is moderate in pressure (verified?), you can probably just load the same and check the accuracy.

If your known powder charge fills your new (fired) brass fuller than your old (fired) brass, you may want to drop your powder charge a grain or two and chronograph to assess any difference the brass is making.

Brass capacity differentials tend to be more pronounced in smaller cases simply because it takes less difference to create a larger percentage impact on the powder capacity.

Thanks for the input guys......

Using a fine ball powder, check the avg. volumn between each brand. If the vol is the same, then you should have no problem. A 5% reduction may be just too much, but certainly safe. I will reduce teh charge wt. by the reductio in volumn. So if the WW are say 75gr & the Nosler 73gr, then I would back off the Nosler by 2gr.

quote:

Originally posted by fredj338:
Using a fine ball powder, check the avg. volumn between each brand.

Why not use water like everyone else? It's even listed that way in load manuals, 'Case capacity in grains of water.'

quote:

Originally posted by rcamuglia:
I have a pretty good load for my .300 Win Mag that I use for some long range target shooting. I developed the load with Winchester brass that I carefully prepped with most every step you can think of except weight sorting.

I decided to buy some good brass; Nosler.

Do you think that I will have to rework the load since I am changing the brass or will it be just fine?

I don't get it? You are already using "good" brass.

Measuring case capacity with either water or ball powder works fine; powder is a little less messy. HOWEVER, measuring the capacity of two unfired cases against one another, or one fired and one unfired, is meaningless. It is only after the cases have been fired in the same chamber and before being resized that you will get a meaningful comparison.

Unless you are shooting a "redline" load, I'd load up some and give them a try. See how they do for accuracy and how do the cases look. You may have to tweek the load around a bit but its probably a good starting point anyway.
If you want to be really careful, weigh 10 of the new ones and ten of the old ones and see how they compare weight wise. In a case the size of a 300, they'd have to be off quite a bit before I'd worry about it.

Thanks gentlemen,

I did weigh each brand of case just to check for differences. I think I'll be ok sticking with the developed load; the differences were a couple of grains on cases that weigh 244gr.


What I meant about getting some "good brass" was that the Winchester stuff varies a ton in weight differences. I've done all the brass prep and they're fine in that regard now. The Nosler brass has everything done for you except neck turning, which I will do even though it's a factory chamber. I have to think that since I don't use the expander ball during resizing, that neck turning has to help uniform neck tension by uniforming the neck thickness.

It's amazing how close each of the cases weigh to each other. I have read guys for and against weight sorting but I figure it has to help by making each case have identical volume, therefore taking the "size of the combustion chamber" out of the variable equation for accuracy.

Any other thoughts?

I just went to the range yesterday.To work up a load for my 270 Win.
I wanted to change from Winchester Brass (prepped except for neck turning) to Nosler brass to see if there was a great difference.
With the same type and amount of powder, primer, bullet and COL it grouped 30% smaller.
I worked the powder amount up but it was the same amount as the Winchester case load for the most accurate just a smaller group(which was repeatable).
Hope this helps.
Nosler brass was three times the price with a lot less case prep time.

Cool! Great news, I hope I get the same results!!

Got an update on the brass change:

Bought some Nosler brass for my .300. Loaded the same load that shot the 1.177" group at 300. Shot a 2" 5-shot group after 5 down a clean cold barrel at 300.

Went to a 100 yard target and it was terrible.

Dialed the 300 yard paper again and group was good.

Dialed a 425 yard 6" round hanging steel gong, played the wind and held on the right side of the plate, and put 2 within an inch of each other on the plate.

The brass was brand new with no fire-forming. The rifle shot OK, but I hope it gets better when all the brass is formed on the second loading.

I checked the primers and they were showing some flattening as compared to the same load in Winchester brass. Could this be because they were new and not yet fire-formed to the chamber therefore the effective combustion chamber size was smaller creating higher pressure?

Or maybe the Nosler brass is not as elastic as the Winchester?

Thanks.

Of all the loads I've worked with in Winchester brass I frankly wouldn't try them in other brass...

In the cartridges I've worked with the most, 30-06, 270win
7mmMag, 338mag, the Winchester brass has a greater capacity than other brands I've compared it to (Remington and Federal)

In my bolt action 30-06 my best hunting loads are in winchester brass, simple because I can fit another grain and a fraction of RL22 into the case.

But I've also found that winchester brass is the mostl likely to crack a case neck while resizing.

I've observed ove rthe long term that when fresh from the tumbler winchester brass is "whiter" than Rem or FC brass
and I think that relates to a higher ZN% (Copper is expensive)

If I had extra money I might use Nosler brass, but frankly I'd be more likely to spend that extra coin on MORE rem brass or more good bullets.

AD

After the brass is fired won't they have the same capacity?

Unless thickness is different?

Besides thickness, also the interieur around the case's base are designed differently with different brands.

When buying brass over a period of time, be careful because also with the same brand weight and thus, volume can vary.

I didn't use the chrono when I tried the new brass. Is it safe to assume that since I'm getting more primer flattening showing more pressure, that velocity will also be higher?

I think I may need to back off by .5 grains?.........

quote:

Originally posted by Allan DeGroot:

But I've also found that winchester brass is the mostl likely to crack a case neck while resizing.

Just an observation...
I used Remmington brass in a 30-06 that had a loose neck. I found the case necks would crack during the 4th and 5th firings. I switched to Winchester and the problem went away. I always figured that it had to do with the annealing during production.

I also noted the difference in color.

No, the capacity won't necessarily be the same. And you are right, the primer flattening could be from the cartridges conforming to the factory chamber. Too bad you didn't have your Chrony along to tell you what sort of velocity you were getting compared to your Winchester brass. Your second firing should tell you more.
If you were pleased with the accuracy of your load in the Winchester brass, one of the things you can do when you start loading with the Nosler brass is to try to duplicate the velocity. This may duplicate the barrel harmonics (vibrations) and save you some powder.

I was out this morning for some more testing. My good Winchester brass load is 75 gr of W-780. With the Nosler brass I noticed some primer flattening at this charge so I loaded 10 at 74 gr. and 10 at 74.5 gr.. The primers looked about the same as with 75 gr..

I chrono'd the loads this morning and think that the 75 gr load will be about the same in both brands of brass. The lighter loads chrono'd about 100 fps slower than the 75 gr load in Winchester brass.

When I originally developed the 75 gr load at 100 yards it shot great; 4 shots in .363" and 1 out that made the entire group .75". I then shot a 5 shot group at 300 that measured 1.177"!!!. It hasn't duplicated that since.

This morning I shot the 74's and the 74.5's at 100 yards and they shot mediocre groups. I then shot a group with the 74's at 300 and it was pretty good....about 2".

Then it happened again....almost! I began a 300 yard string with the 74.5gr cartridges. The first three shots grouped at .75" at 300 yards!!!!

Well, I know a group isn't 3 shots so I loaded the chamber with another and squeezed. It printed about 2" high and so did the fifth shot

Oh well.........

At least I think the OCW is 74.5 to 75 gr!