6mm Creed from 6.5 Creed Lapua

[Hengehold]

If I neck a Lapua 6.5 Creedmoor case down to 6mm Creedmoor, does the neck thickness of the brass change? If so, how much?

Based on other threads in this forum, it may require neck turning.

Yes, I know Lapua already makes 6mm CM brass but it only comes in SRP.

-TH

 

[tharger]

I have changed 6.5 cr to 6 cr in a lot of different brass. Not noticed any problems. Haven't measured though

 

[Laurie]

I can't comment on the Creedmoors, but necking 308 Win Lapua brass down to 7mm-08 thickened necks by around a thou', so a two-thou' overall clearance reduction. In a 7mm-08 minimum SAAMI chamber, this needed neck turning as out of the box 7mm-08 Lapua neck thickness was at the top end of allowable loaded-round O/D in this chamber. Winchester brass is much thinner-necked and necking it down wouldn't have been an issue, nor probably in a typical factory rifle chamber.

Obviously though it depends on your 6mm Creedmoor chamber dimensions. If a factory rifle, there may well be enough clearance. Neck some cases down, load them with a mild load and see what MVs / pressures are like, also whether a bullet will slide into the fired-case necks. If it does, you're good to go.

 

[Bill K]

I might, you would just have too measure before and after, then trim the neck, if necessary. Just another step, often needed in reloading and forming new cases.

 

[spudgun]

I necked down 100, 6.5 CM Starline brass to 6mm CM.

That was 2 years ago and so far no big issues only maybe 5-10 neck cracks.

This brass has been reloaded over 10 times each case and I am very pleased with Starline brass.

 

[Hengehold]

I necked down 100, 6.5 CM Starline brass to 6mm CM.

That was 2 years ago and so far no big issues only maybe 5-10 neck cracks.

This brass has been reloaded over 10 times each case and I am very pleased with Starline brass.

thanks for the info. What is the neck diameter of your chamber?