300 win mag reamers

[parker_chp]

I am building a 300 win mag to shoot ELR with and am wondering if anyone can give me some specifics about the available reamers that work well with the 215 and 230gr bergers. I have a stiller predator long action which is already cut for extended mags, an xlr chassis setup for cip length mags, and a 30" 5r 10tw bartlein blank. I looked at pt&g's website and they have a cip length and a few others military versions. I'm just curious what other people are having success with. Any info is appreciated.

 

[Minesweeper3433]

If you can get a hold of Mike Bryant he has done some crazy accurate 300winmags in the past. One of them was mine. If your loading the 215 and 230 you might want to single load unless you need repeating capability. I had a load worked up with 200 hybrids for repeating on mine and 215's for single loading. Get Norma or RWS brass and only use that brass.

The 300winmag he built for me would frequently shoot 3 shots into .4 inch at 200 yards when I was in FL. Now that I have moved a bit west I use the 300RUM for a bit more speed with the 230's.

 

[jsthntn247]

You want a reamer with a freebore in the .220-.270 range

 

[FatBoy]

Another option...

Pick the brass and bullet you want go use and send a couple dummy rounds to PTG, Clymer or whomever you prefer and spend the $175 for one designed exactly to your needs, to incude the tightness of the base, lead angle, etc.

I'm building with am A191 chamber. If I can't get enough powder in the case with a 220 i'll buy a throater and push the throat out. You can order a throater with the specific angle for the bullet you decide on.

 

[cdparker]

Before you start this project, you might want to go to Berger's web site and run your bullets of choice through their stability calculator. I don't think that you can get either of those bullets going fast enough to comfortably stabilize in a 10 twist barrel. However, if you use the Berger OTM hybrid bullets, you should be OK. Years ago when we were shooting 250 and then 240 gr Sierras at 1000 yards, we had to install a 9 twist barrel. We also had to be aware that near the middle of the string; it was important to pack up and crawl back up to the firing line where we started. The heaviest bullet that we shot with the 10 twist was a Sierra 220 gr. MK. I had the best luck with some of Rick Mulhern's 210GR (IIRC) Delta Bullets.