300 RUM--OAL Trouble

[Hired Gun]

Don't sweat the chasing the lands thing. A lot of free bore can be a wonderful thing. Set your seating depth where it feeds nice and leave it alone. Then adjust charge weight for the desired speed and go shooting. I never did find the top end for the 210 Berger in the 300 Ultra. I just quit at 3200fps. It shoots 1/2" from 2800fps on up. This is the internet so be wary of any load data. I shoot over 3 chronos at a time so I'm pretty confident of my indicated speeds. I also only use Lee Collet Dies so my stuff shoots pretty good no matter what I do. I do no other case prep other than chamfer the necks on new brass. It's a waste of time and I don't waste any money on all the little gadgets that are designed solely to seperate you from your money.

For you I would start at 94 grains of Retumbo and move up in 1 grain increments. Then dial to the exact speed you are looking for.

In the 300 Weatherby I ended up using more 7828 than what my max load was for the 200 Accubonds. I believe the 210 has less bearing surface or the freebore is so great it just doesn't build a lot of peak pressure.

I use CCI-250 primers in everything from 22-250 through 338 Lapua.

 

[knc1105]

The rifle shot really well but I have never loaded that far off the lands. I do not remember ever loading over .020 off most were .010. The reason I wondered about throat life because I have heard alot of talk at matches from people that I know and trust talked about how they really increased their barrel life, loading to the lands and using Superior Shooting Systems.com throat maintenece system ( TMS ) Everything I have heard about the Bergers was you had to load them close. The guys that shoot the 6.5x284 literally count the rounds when they start fire forming a small lot of cases and know how many matches they can shoot before they set the barrel back. I would assume that the 300 RUM would eat barrels like that. I shoot ALOT and in 3-weeks we are getting a new 1,000 yard range 25 minutes away. The range sets about 10-15 degrees off our prevailing winds, so it should be a fun place to shoot. It was supposed to already been open but neighbors sued and slowed him down. Happy Hunting, Ken

 

[Hired Gun]

I quit thinking about how far to the lands when I got bit by the Weatherby bug. All my rifles are loaded way off the lands and most all shoot pretty well. The biggest issue has been bullet type rather than how fast or what powder or how far off the lands. If it likes the bullet it usually works about any way I can get it down the barrel.

 

[bigbuck]

Don't sweat the chasing the lands thing. A lot of free bore can be a wonderful thing. Set your seating depth where it feeds nice and leave it alone. Then adjust charge weight for the desired speed and go shooting. I never did find the top end for the 210 Berger in the 300 Ultra. I just quit at 3200fps. It shoots 1/2" from 2800fps on up. This is the internet so be wary of any load data. I shoot over 3 chronos at a time so I'm pretty confident of my indicated speeds. I also only use Lee Collet Dies so my stuff shoots pretty good no matter what I do. I do no other case prep other than chamfer the necks on new brass. It's a waste of time and I don't waste any money on all the little gadgets that are designed solely to seperate you from your money.

For you I would start at 94 grains of Retumbo and move up in 1 grain increments. Then dial to the exact speed you are looking for.

In the 300 Weatherby I ended up using more 7828 than what my max load was for the 200 Accubonds. I believe the 210 has less bearing surface or the freebore is so great it just doesn't build a lot of peak pressure.

I use CCI-250 primers in everything from 22-250 through 338 Lapua.

I wouldn't start at 94 grains of retumbo ! 91.5 grains of retumbo and my bolt gets sticky . Your rifle may be different but i would work up as 94 is on the high side regardless of who's rifle is being used !

Bigbuck

 

[Hired Gun]

Bigbuck, you are right. Is your rifle a custom or a sloppy factory rig? What primer? Was that really hot weather? Were you seating in the lands? All have affects on pressure. 88 grains is the official starting point. Being safe and conservative is always a good idea.

 

[tnshooter111]

I have a sendero II in 300 rum and have to shoot on the low side of all loads because of sticky bolts and primers blowing back. The OAL is a problem for me as well. All I can do is set it to box length. I have put about 300 rounds through it so far and an inch is about all it will do. When I was in the break in process it seemed to shoot a little better but now the more rounds throught it the more it is opening up. I love the gun but just wish it shot a little better.

 

[bigbuck]

Bigbuck, you are right. Is your rifle a custom or a sloppy factory rig? What primer? Was that really hot weather? Were you seating in the lands? All have affects on pressure. 88 grains is the official starting point. Being safe and conservative is always a good idea.

Hired Gun, I have a semi custom rifle or some would call it a custom . It started out as a sendero 300 RUM now it wears a trued 700 action defensive edge recoil lug defensive Edge break. Barrel is floated back to within 1 1/2 inch from the recoil lug you can run a buisness card all the way down ooops I almost forgot it wears a broughton heavy barrel that gives me that tingly sinsation down inside , that is when I pull the trigger on it .

you made a good point as I'm .020 off the lands and it was really HOT weather 93 degrees. My primer is the federal 215 Match, Nosler custom brass retumbo powder 210 Berger that loves brown hair LOL .

Shoot safe !

BigBuck

 

[knc1105]

I got in my Wyatt's box but gunsmith gone till Monday, so what I am going to do is load some closer to the lands and load them single shot to see what happens. If it helps the groups I'll have it installed.

 

[freebird63]

I am by no means even close to calling myself even an amateur gunsmith, but the wyatt is very easy to install, unless I believe the centerfeed once might require more then the window box. But after do some more inspecting and checking my gun out. I was under the impression that my length to the lands was 3.150 with a comparator, but loaded up a dummy load and found out that the actual length to the lands is 3.210 with a comparator, base to tip is 3.890, so that load won't fit in my magazine. Tomorrow will tell me if I am shooting loads at the lands or if I can get away with a shorter load. At first I had a problem with my rifle being a single shot, but hey it only takes one shot and he's dead.
This sendero 300 ultra mag has been very interesting and trying on my patience. Hope my next big gun is more forgiving.