Can I start load development with new brass?

[Nicholas]

I have some new lapua brass coming this week, I am finally ready to start reloading. It will be for a 308 win. I am not going to neck turn the brass. The rifle has a good custom chamber that allows me to shoot federal match and black hills match ammo without any problems. Don't know the exact specs of the chamber.

I was just wondering if there is a big difference between new brass and fire formed brass?? Can I start load development with the new brass or do I need to fire-form it first?

 

[Dave King]

I shoot the new brass and only notice a little tightening of the group size once I've fired the brass once. I use the Lapua brass in my 308 too, great stuff.

 

[Nicholas]

thanks, the great to hear. I will post my results.

How much bullet jump do you set on your 308 win??

[ 05-13-2002: Message edited by: sr90 ]

 

[Dave King]

For my latest rifle I load to max. OAL for the 308 (2.880 I believe) as it's a short action M40A1 style (match chamber designed for Fed GM & 175's) . I use varying amounts and can't recall the load for the M24 I had.

 

[Guest]

SR90-
Start with about 42 gr of Varget(working up to about 45 gr.) under a 175 gr or 168 gr SMK seated just touching the lands(working out to about .015 off). I also use Fed210M primers. I use LC89 Match brass with 42.5 gr Varget/Fed210M primer/175 SMK/.005" off. This load chronos about 2775 from my 28" barrel. It is a good starting point.

 

[Guest]

I usually increase the powder charge by .5 gr increments. I am using a lighter charge(42.5 gr) because of the thickness/weight of the LC brass. Good luck w/the load development!

 

[Nicholas]

Hey how did you know I was using varget?

I also will be using the fed 210M

What grain increments should I increase the loads from 42-45 grains?

I was planning on having the bullet just kiss the lands during my initial testing while increasing the powder load. then after I found a good load then start backing the bullet away from the lands to see where to seat them.

Am I on the right track guys?

[ 05-13-2002: Message edited by: sr90 ]

 

[Brent]

The same load might be 1/2gr off, maybe, in the fireformed brass later but not too far if so.

I checked for that on a load of mine too and .5gr more powder in the fireformed brass resulted in the same large groups as was observed during load initial development. Groups went from under 1moa to over 4moa in .5gr, so over a .5gr jump, in my book, may leave a good load undiscovered.

That said, I don't think that load will be very tolerant in other than the testing conditions it was first fired under.
I have found several loads to tolerate a full 1-2gr swing in charge wt. before opening up measurably, these are the best, at least the most usefull up here where temp swings are big. We can compensate for a velocity change but the group size has to hold. In this particular case, a .5gr drop produced over 2moa groups as well, so it's a fine line with this one.
I shoot the 308 quite a bit too. I've heard more than a few times that fliers were because of the GM210M primers and CCI BR-2's solved some of these issues. I switched to the BR-2 for a while but haven't tested strictly for this yet. 165gr Gamekings over 44gr Varget at 2.85" and 180 Scirocco over 43grs are great loads in a couple rifles we have. IMR 4064 has given me some outstanding new groups with the GK bullets lately, maybe even better than Varget.

[ 05-16-2002: Message edited by: Brent ]