I am getting ready to build a 300 prc and I plan on shooting Berger 220s or 230s . Any advice on whether or not to use a saami spec reamer or custom reamer would be appreciated . It appears a lot of people shooting the big heavies in 300 prc are seated out longer than custom guns . Are the custom guns being built less freebore ?
- Thread starter whodat988
- Start date
What magazine setup are you using? I had a .050 jump with a Saami reamer and 245 Bergers at CIP+ detachable mag length (3.850). 230s I forget the exact measurements but it was still a solid jump.
245s shot great though. Ended up shooting best at a .100 jump.
245s shot great though. Ended up shooting best at a .100 jump.
You wont need a custom freebore to shoot 220’s or 230’s.
I know it sounds silly but I’ve had that bottom metal sitting in the safe so long I forgot the brand but I believe it Wyatt’s . I will try the 245’s and I can even load it like a single shot if it ain’t liking a jump
Bergers are incredibly tolerant to various seating depths.
I know this will sound like blasphemy to members of the church of reloading, but I can basically load a random OAL with Bergers and they will shoot well.
Saami reamer with a 0.5345 or 0.535 base. Generally referred to as an AW2 spec reamer.
Many reamer makers are using this size base by default due to extraction issues with 0.533 chambers, but it's best to make sure.
Many reamer makers are using this size base by default due to extraction issues with 0.533 chambers, but it's best to make sure.
To drive this point home, this is a pic from Tuesday afternoon when I went to the range to #1) get my scope zeroed and #2) put some rounds (Berger 155 Full Bore) through my newly rebarreled 308. To do so, I picked a random charge (43.5 gr of Varget) and a random seating depth (.110 off).
So, I set everything up, chambered a round, then thought to myself, "shit, I didn't bore sight this thing!"
But I was like, what the hell. Send this one down range and see what it does. It was one of the three to the lower right. I fired a couple more, patched the barrel, adjusted the scope, then aimed at the top circle. Those are shots #4-6 through the barrel. Then 5 more at the left circle.
These wouldn't win any benchrest competitions, but for the first 11 rounds through the barrel with random everything, I'll take it. I'm sure this will tune down nicely.
Yes, Berger hybrids are the bomb. With that said, you do gain by tuning seating depth, but they will still shoot pretty darned well if you don't.
