Gunsmithing 300 Norma Freebore Help?

[Kino]

Looking to get my own 300 Norma reamer and was wondering what freebore would you guys recommend andmhad good luck with for the Berger 245 Hybrids and 230 Hybrids??

I really want to run the 245s optimized to run through a CIP magazine. I have zero intention to run anything else other than these 2 bullets from Berger, much appreciated for your experience and thoughts!

 

[Jackomason]

I ran the standard Manson reamer, if I remember it's like .215 +/-. I don't think I'm lacking anything over a custom reamer.

 

[surgeon260]

Just to give you a data point - I could not get the 245s to shoot nearly as well as the 215s out of my 8.5 twist Norma improved. 215s at around 3200 were consistently one ragged hole, while 245s were closer to 0.75 MOA. I had way more flyers with the 245 that I could never eliminate. Both with N570 and Lapua brass. YMMV, just some food for thought before you throat specifically for the 245s. I know plenty of people love the 245s though.

Also keep in mind that 245s at max length with bearing surface above the neck-shoulder junction still won't fit in most CIP magazines. You will need something like the Long XL Lapua magazines from UM or a Wyatt's box. Which then begs the question - why not move up to the Lapua case and really get those 245s moving?

 

[Schw15]

I run the 245 in 300 norma improved and have great luck with them shoot amazing. N565 and n568 is what I use. I mag feed them in cip 338 lapua mags 3.720ish is overall length. My speeds are not eye popping like others but working on new load now with new barrel I'm going to be 2900 to 2950 in 32 inch barrel but I look for consistency rather than an extra 100 feet.