Changing Bran of Brass-how much does this effect a pet load?

[dougduey]

A question for all of you seasoned reloaders out there. I usually use one brand of brass and stick with it once I have a load worked up. Recently, I purchased another brand of brass since I got such a great deal. How much will this effect my pet load and what kind of new load work up do I need to do?
This is for my 6.5-284 Norma. I used Nosler brass, but now I have a bunch of Lapua brass.
My pet load is 57.6gr Retumbo, 210M primer, 143 ELDX. This load is pretty much at max in my rifle with the Nosler brass.

Thanks
Doug

 

[ifgator]

A question for all of you seasoned reloaders out there. I usually use one brand of brass and stick with it once I have a load worked up. Recently, I purchased another brand of brass since I got such a great deal. How much will this effect my pet load and what kind of new load work up do I need to do?
This is for my 6.5-284 Norma. I used Nosler brass, but now I have a bunch of Lapua brass.
My pet load is 57.6gr Retumbo, 210M primer, 143 ELDX. This load is pretty much at max in my rifle with the Nosler brass.

Thanks
Doug

I'd be interested to hear what you find out. I would be interested to know the difference in the spent case capacity in grains of H2O between the 2 brands.
Keep us posted!

 

[FURMAN]

The best way to find the difference is measure the average of ten or so of each brand of brass. The more it weighs the less case capacity. With less case capacity the load will have to be reduced and worked back to the node.

 

[WeiserBucks]

^^^^^^^^^ TROOF ! ^^^^^^^^^^

Lapua brass is awesome, you'll never turn back .

 

[bigedp51]

Smaller cases like the .223 are effected more by capacity variations than larger cases.
Below a Lake City case at 30.6 of H20 capacity and the older Lupua cases with 28.0 capacity can cause a 6,000 psi difference with the same charge of 25 grains of H335. This information comes from Quickload and the first thing you need to do is measure your case capacity when using Quickload.

 

[General RE LEE]

I ran across this thread cause I swapped brands of brass today and had an over pressure situation. With Remington brass my pet 7mm STW load is rather mild. I switched to Nosler brass and the case swelled and I couldn't get the bolt to pull back.

Nosler brass evidently created a higher pressure situation than the Remington brass I worked up the load. If I want to use the Nosler brass I will have to start lower and build up.

 

[Barrelnut]

If I want to use the Nosler brass I will have to start lower and build up.

Yes. Norma brass it much thicker in the case walls and web than Remington brass. If you weigh the Remington against the Norma you will find that the Norma is much heavier and therefore has less volume for powder which raises pressures. Gotta be careful changing brass.

 

[Rick Richard]

As mentioned, any component change may put you in a dangerous situation. One time I went from Winchester brass to Federal brass and was popping primers. So, always back off a bit when any changes are made and work back up.

 

[Greyfox]

It's been quite a few years since I have used Norma brass in my 6.5x284's, but when I did, the capacity, velocity, accuracy, and ES differences compared to Lapua were not enough to require any adjustments using my optimized load: 57gr of Retumbo/Fed210M/140HVLD. I consider both to be good brass. I bought a batch of Hornady 6.5x284 brass at the time and it wouldn't even chamber in my rifles.

 

[FEENIX]

A question for all of you seasoned reloaders out there. I usually use one brand of brass and stick with it once I have a load worked up. Recently, I purchased another brand of brass since I got such a great deal. How much will this effect my pet load and what kind of new load work up do I need to do?
This is for my 6.5-284 Norma. I used Nosler brass, but now I have a bunch of Lapua brass.
My pet load is 57.6gr Retumbo, 210M primer, 143 ELDX. This load is pretty much at max in my rifle with the Nosler brass.

Thanks
Doug

YMMV to any changes in components, and sometimes different batch #s even with the same brand might also affect initial load due to manufacturing batch process variation. As others noted, always proceed with caution.

 

[Greyfox]

With over a dozen years of 6.5x284 Norma shooting with a few different rifles, I dug into my records. As mentioned in my previous post, while I did some early loading with Norma(Nosler) brass, the majority of my shooting has been done with Lapua brass, but results were quite similar using the same load parameters between the two cases. The neck-wall thickness between the two were the same at .015" which allowed me to use the same neck bushing(.292") in my full length dye. Headspace(-.002") was also the same with that dye. The Norma case bodies were thicker at 5gr heavier in weight compared to the Lapua brass(201gr) and, the Lapua brass capable of approximately +2gr of Retumbo before compression. However, with a charge weight of 57gr, and the same seating depth(.075" OL), velocity, accuracy, and ES were quite close. While, at the time, I chose to maintain my velocity of 2965FPS. Using the same bullet seating depth, I could increase my charge weight using Lapua brass as much as 2gr of Retumbo(mild compression) for a velocity increase of 50FPS. My Norma/Nosler brass information is about 10 years old, and I have not worked with recent lots. My Lapua brass information spans +10 years, and I have seen no variation in case dimension over this period
If I were the OP, I would do a similar comparison of the Nosler and Lapua case dimension/capacity and, to be be safe, do a load work-up starting a couple of grains less then his current Nosler brass load. With all likelihood, current results should be able to be duplicated with the Lapua brass. IMO

 

[DoneNOut]

More than H2O case capacity relative measurements between brass brands, there are metallurgy differences as well. Some brass flows different when pressures generate upon firing. Swelling the chamber at different rates. (N stuff like that)