.338 Lapua CIP Reamer - Need some advice

[RHunter]

I am in the process of getting everything together to build a 338 Lapua on a CADEX and I have ordered the chassis to accept 338 CIP mags so I have the luxury of a bit of extra length.

I am curious what reamer to use? Standard Lapua Mag will allow me to shoot Lapua ammo in a pinch but since I am a shooter that can usually perform close to the limits of the rifle and hold half MOA fairly consistently I am thinking I could squeeze a bit extra performance out of the CIP with 300 Grain pills. I tend to push everything else I load long and hard.

Problem is, I have no idea what the pro builders are using for a reamer # in a CIP gun.

Can someone help me out with this?

 

[RHunter]

Anybody??

 

[cowboywhorses]

You can run a throating tool to get more length out of the chamber. This way you can stop that will work for the gun. Also look at get your hands on various reamer prints, someone may have done a longer throat on a different gun already.

I like to try and get the boatail of the near the botttom of the neck junction. But this may not work for your a applicxation.

I guess you will have to shop around.

 

[RHunter]

Also look at get your hands on various reamer prints, someone may have done a longer throat on a different gun already.

That is pretty much the info I am looking for.

 

[RHunter]

anyone??

 

[ELR researcher]

RHunter:

There are two drawings posted on my site (one specifcially for 300 gr), plus the CIP sheet - Information - Cartridges That said, that porvides ZERO info on what the top smiths are using.

Frankly, I'd call Dave Kiff at PTG and ask him what he'd suggest (what the "best" smiths are ordering - if not proprietary).

Unclear whether you'd consider a 338 LM variant. Check the Cartridges Matrix I recently added, might provide some insite on options - http://www.elr-resources.com/ELR Cartridges Matrix 12252013.xls It's an Excel file. If you need Microsoft's free reader its here - Download Excel Viewer from Official Microsoft Download Center

 

[CoryT]

Get a magazine, then load one each dummy round to mag length. Now measure to the ogive, then spec the reamer to set the throat -.005 or so from the longest round. That should set you up for a short jump at max length, and let you seat a little deeper to find the accuracy node. You could also set the throat to the shortest round, then just seat the long ones a little deeper.

 

[RHunter]

Good info, thanks!

 

[RHunter]

Get a magazine, then load one each dummy round to mag length. Now measure to the ogive, then spec the reamer to set the throat -.005 or so from the longest round. That should set you up for a short jump at max length

I am liking this idea...

From what I can gather, Berger 300 grain hybrids are not overly jump sensitive like the VLD designs are so what I am thinking is loading that dummy round with a 300 grain Berger hybrid at CIP length and sending it to PTG and get a custom reamer specifically for that combination.

And this leads to another question:

What would I use for brass? Out of the box new Lapua or a case that has been sized with the dies I have? I have a set of Lyman Deluxe for 338 but have no clue how the sized brass out of a lymann die compares to a case sized in a Redding die. Half my dies for other calibers are Lyman and the other half are redding and to be honest, I think both are equal in quality (outside a redding match set of course)

I guess the risk of sending a dummy load with a case that has been sized with the dies runs the risk of being smaller than factory new and that would force me to size all new brass prior to use... Which is not a bad thing to do anyway... so that is probably not an argument to make in the first place, it is more a hint to my occasional laziness.

My biggest worry with this build is spending all the money and ending up with a rifle that I can shoot to its accuracy limits when I would prefer a rifle with an accuracy limit I have a hard time reaching. I want something that leaves room for personal and load improvement, rather than one I hit an accuracy threshold with.

 

[CoryT]

I'd just use a new case, then you can set the die to just bump the shoulder .002 and be good when you need new brass, or end up with some factory loads.