Neck Lapua 6cm brass up 25 cal

[Deleted member 107666]

Few questions...this rifle will be for range fun, mostly, part-time hunter.

6cm availability of brass and bullets is what led me to snag components for a new 6cm rifle. So far SRPs and 6 creed lapua brass is stocked. Now, the 25 creed seems to have 135 LR hybrids available frequently to pair with the 131 blackjack. Same 6cm parent brass can be used, same SRPs and the same 4350 powder.

For those who shoot both or went one over the other, can you provide some inputs/recs? They both seem pretty easy to load for, obviously recoil is going to increase, between 105s at 2900 fps in the 6cm or 131s at 2900 in the 25 creed.

Losing the factory ammo option of the 6cm. Worth it for a little extra pop to build a 25 creed?

If so...anybody have a good thread on how to necking up brass? As simple as an expander mandrel to open and a bushing to size back down?

 

[K.E.C. Darkside]

Howdy, all 3 cal. brass you mentioned are readily available. I have not resized any to do what your asking. But I would like to tag in to see if someone has, just in case.

 

[Deleted member 107666]

Howdy, all 3 cal. brass you mentioned are readily available. I have not resized any to do what your asking. But I would like to tag in to see if someone has, just in case.

Lots of folks on snipershide necking up/down lapua brass in 6cm or 6.5cm...I do see alpha brass avail for 25 creed...that doesn't do me much good when I just bought 300 pcs of 6 creed

 

[K.E.C. Darkside]

Lots of folks on snipershide necking up/down lapua brass in 6cm or 6.5cm...I do see alpha brass avail for 25 creed...that doesn't do me much good when I just bought 300 pcs of 6 creed

Howdy, I haven't looked, but Graf and Son sales Peterson brass 25 creedmore. And yes necking brass is one way of doing it. But it stresses the brass and you should anneal in that process to keep the brass from prematurely splitting. IMO. But if you have 6. 243. And you want 25. 257cal. That should only take running the 25 creed sizing die into the 6mm and your good to go.

 

[lancetkenyon]

I necked Lapua SRP 6CM brass up to .255 for my 25CM. Easy, one pass. Just lube the inside of the necks.
In my other 25CM, I am running Alpha SRP 25CM brass.
Berger has the 133 Elite and 135 LR Hyb in .257.

Screw Blackjack. They are taking money and not delivering goods. I ordered and PAID FOR 2K of the Blackjacks in Dec 2020. Still nothing. All communication stopped in May of 2021. STAY AWAY FROM BLACKJACK!

 

[K.E.C. Darkside]

Wow, that's terrible. I think I heard that from others about Blackjack. What a shame. The creeds are nice to work with.

 

[sable tireur]

Wrong thread.

 

[Deleted member 107666]

View attachment 414392

https://www.midsouthshooterssupply.com/item/0011511472/7mm-stw-unprimed-rifle-brass-25-count

$3.70 per piece for nosler brass? Nope. I'll take lapua 6cm brass all day and neck it up.

 

[willfrye027]

Necking up 6 creed is very easy. Between 6cm and 25cm, you're getting more recoil but better long range ballistics from the .25 cal. Haven't shot a 6 creed much but throw some numbers in a ballistic calculator and you can see where the .257 runs away from the 6mm. For hunting I've been extremely pleased with terminal performance from the 135 berger.

 

[Kimber7man]

I'm going to build a 25 creed and will try two methods with Lapua 6 creed brass: neck down 1X fired brass out of my 6 creed with .253 bushing, and will neck up virgin brass with a .254 mandrel. See which one works better.

 

[Deleted member 107666]

I'm going to build a 25 creed and will try two methods with Lapua 6 creed brass: neck down 1X fired brass out of my 6 creed with .253 bushing, and will neck up virgin brass with a .254 mandrel. See which one works better.

If you neck up .254, then it springs back that .001 to .253, you're gonna have a bunch of neck tension, no? I was thinking .256 expecting. 001 springback, should end up with. 002 neck tension?

 

[willfrye027]

If you neck up .254, then it springs back that .001 to .253, you're gonna have a bunch of neck tension, no? I was thinking .256 expecting. 001 springback, should end up with. 002 neck tension?

With the lapua brass .282-284 bushings will give you the right amount of neck tension. I don't recall the exact expander mandrel I use for the first firing but it gives .001-.002 neck tension. On subsequent firings I just use the bushing to set neck tension and do not run a mandrel through. Different ways to skin a cat..

 

[Deleted member 107666]

With the lapua brass .282-284 bushings will give you the right amount of neck tension. I don't recall the exact expander mandrel I use for the first firing but it gives .001-.002 neck tension. On subsequent firings I just use the bushing to set neck tension and do not run a mandrel through. Different ways to skin a cat..

On 6mm lapua? I am fairly junior as far as reloading goes, im probably missing something, so can you help me understand how a .284 bushing gets you .002 tension on a .257 projectile.

 

[Axl]

On 6mm lapua? I am fairly junior as far as reloading goes, im probably missing something, so can you help me understand how a .284 bushing gets you .002 tension on a .257 projectile.

The .284 is the outside dimension. Then you have the neck wall thickness (.012 to .015) x 2. so the inside dimension will come out around .002 tension