338 Lapua Improved reamer

[OrphanMaker]

Hello, I was wondering if anybody on here has used the 338 Lapua AI reamer from 4D reamer rentals and what the seating distance to the lands would be for a 285 eldm or any bullet. I have emailed and was just told it is a Sammi spec reamer. I would like to hear from real world experience since there are so many variations with the 338 AI. My main goal is to determine what magazine system I will need to run so I can get going on having a stock built.

 

[tobnpr]

To maximize mag length you need AICS pattern CIP length mags, and you need an action and bottom metal cut for it.
Std = 3.65 OAL, CIP length = 3.77

Accuracy International Magazines

Accuracy International Magazines

www.area419.com

Since you're feeding from the mag, you'll obviously need to keep your OAL within that constraint.

 

[74honker]

Accurate Mag also makes a 3.850 and now a 4+" box mag.

 

[OrphanMaker]

Thank you for the replies. I'm not necessarily interested in running the big box just because. I'm looking for actual numbers on a reamer so I can plan accordingly.

 

[74honker]

Not AI and not from 4D but I'm getting a standard done shortly. They have 2 reamers, 1 speced for 250g SMK and one for the 300g SMK. Told me that there's roughly .040-.050 difference in the throat. If that helps any.

 

[OrphanMaker]

That helps a lot! Thank you!

 

[74honker]

Of course everything comes down to personal preference and what you want for an end goal. Even though I'm planning to mainly run the 300s, his recommendation was to go with the 250 throat. Although I may have to seat the 300s a little deeper in the case and lose a little powder room, the gains will be a little more flexablity over a wider range of bullets and extended barrel life since I'll have that extra .040-.050 to give to chase the jump as the barrel wears. I don't plan to burn it down like a roman candle so this makes sense to me lol.

 

[tobnpr]

Mine is SAAMI. Not AI, but that's irrelevant- nothing forward of the neck/shoulder junction changes.
Loaded with 300 A-Tips, at 3.8 OAL provides .020 jump.
Close to mag length capacity- I could squeak out another .040 or .050, which will be the case as the throat erodes.

I don't want it throated any longer (as a smith, I can easily do it) because the mag length just isn't there to use it.
Different story for single loading- but here, mag length IS going to be your constraint. I would carefully consider the "advantage" of a longer throat because you're going to end up with a lot of jump you may not want as the throat erodes (and it will, quickly- if you put any number of rounds down the tube).