bigcountry

I have trouble understanding guns sometimes. I have a 700BDL SS in 300RUM. I have tried all kinds of powders, seating depths, and factory loads. Still can't get groups down below 1.5". And thats letting the gun cool 10 minutes between shots, and cleaning every 5 rounds. Pillar bedded and trigger set to 2.5lbs. The COL with Nosler PT 180g is 3.750" touching the lands. With Speer GS 180g, the COL is 3.660" according to my Stoney point.

Saw a tactical 700 with bull barrel, bipods, sling, Leupold Vari-III 6-20X50 and H-S stock in 300RUM for 1100 dollars that the owner said only had 20 rounds thru it. So I take to the range to compare. First 5 shots had 4" groups. I was so disappointed. So I cleaned, and this thing had copper build up so bad, it took me a half hour to clean out. So, next 4 rounds got .8" groups and 2.5" higher. Guy didn't know how to clean or break in, I guess. At 200 yards, I got 2" groups shooting one round after the other, no cool down. Went home an measured the COL with my Stoney Point, and its worse than the BDL. With same noslers, it is 3.810" and 3.706" with Speers But shot great with Factory ammo with COL at 3.55". I don't know if its the bedding on the new gun, the bull barrel or what.

AJ300MAG

I've heard that when the .300 Ultra Mag first was released Remington was using a lot of free bore. Last year I picked up one of the "Rocky Mountain Elk Foundation" limited edition SS BDL .300 Ultra Mags. I assumed it had the same amount of freebore. Checking things out I found that the throat wasn't excessive as in the initial run of ultra mags, I could load most bullets I have around to where they touch the lands but still fit the magazine. So I put a scope on it and took it out to break in the barrel. Wasn't impressed with the recoil, so I ordered a Vais muzzle brake. When I installed the break I found that the crown was off center by a bunch, had to take .050" of the end of the barrel to get rid of old crown, and recut a new one. Took the gun back out to the range, fired a few shots at 50yrds to confirm scope was still at zero, Shot a 7/16" 3 shot group at 100yrds, shooting Nosler 180gr Partitions with RL22 powder. Since then I've reworked the trigger, hope to make it out this week to do some more load testing. I also plan to change to a fiberglass stock to see if it makes a difference.

bigcountry

AJ, when you say the crown was out of round, how did you find that out? Is is something, I can do? Or did the guy installing your Vais find it.

AJ300MAG

I installed the brake myself. I used an arbor to indicate the muzzle end of the barrel to run true in the lathe. When I started the lathe I noticed the crown was running out of round. I checked the bore again and it was within .0005". So I threaded the end of the barrel for the brake, and recut and lapped the crown. You could have your local gunsmith look at your rifle and check it. On mine you could visualy see that the chamfer in the bore was heavier on one side. Being a Toolmaker has its benifits when it comes to doing machine work on firearms. I'm realy curious if the added weight on the end of the barrel improved the accuracy, I didn't shorten the barrel when I installed the brake, it's still 26", 27 1/2" with brake installed.