6.5-285 Norma or Win Chamber?

[jclimb1]

Hey folks, long time lurker first time posting. Thanks for all the great info over the years!

I'm looking to build/have built a primarily long range target rifle in 6.5-284 (Rem 700 base) and I've been reading a bunch about it lately. The nearest reputable smith that can tune my action and install the barrel that I've selected in a reasonable amount of time suggests the Winchester chamber for this cartridge over the Norma chamber. I've found a number of posts regarding the differences between the two but I'm honestly having a hard time wrapping my head around how it will affect me and my shooting and reloading.

I'm planning using 142 SMKs and will probably shoot 600-800 yds max at this point. Want to use lapua brass, redding dies (S bushing for neck).

So, norma chamber if I anticipate longer bullets into the lands, correct?

How would the winchester chamber affect what I can and can't do reloading or shooting wise?

If there is any additional info I can provide to better quide this post, please ask.

Thanks!

 

[BrentM]

The norma chambering allows for more seating room of the VLD type bullets as you have described. If you choose the Winchester chamber the bullet is seated further into the case and that reduces case volume for slower burning powders.

For whatever reason my rifel like .090 to .100 off the lands so the norma chamber is perfect for me. Both the 160 and 140 shoot well from .075 to .100. I have had luck at .015 off with Target VLDs but I don't shoot them anymore. Just hunting bullets.

 

[jclimb1]

Thanks, that's helpful. I've been reading more, found some posts and topics indirectly related.

If I run the Win chamber, would it be pointless to try to use the longer bullets? Do they just not perform when pushed farther into the case?

Also, would the win chamber be a better choice if I wanted to run lighter bullets? Or stated inversely, do I loose anything with the longer throat of the Norma chamber if I end up primarily loading 120 gr bullets?

Thanks!

 

[Truc]

also you may have problems using the Lapau brass. I had the Winchester Reamer used on my one and only 6.5x284 and Lapau would click when opening the bolt, switched to Winchester brass and no problems.