R25 in 257 Weatherby?

[Bob33]

I shoot 100 grain TSX and TTSX bullets out of a 257 Weatherby. The load I use is 72 grains of Reloder 22. I get velocities right at 3600 ft/second.

I have a friend that says he uses 75 grains of Reloder 25 with the same bullets, and gets a little over 3700 ft/second.

The Alliant website does show 100 grain loads with both powders.

Does it sound prudent to try R25 with 75 grains?

 

[jayran]

I have the same gun but shoot 115 bergers with 68gr of RL25 @3060fps. I would say 75gr's as high as you would want to go.

 

[Iron Worker]

Go to reloadersnest.com there is a poster named "Hired Gun that shoots 110 Accubonds with 74.5grs of Re#25 for a MV of 3,511. 45 degree temps and says approach load with caution.

 

[AZShooter]

I may get myself into a jam but we built five 257s and all use RL-25 with the 115 Bergers. All bullets are moly'ed and all barrels are 3 groove liljas. This combinations screams. We(Dan, Tim, Allen and myself) are using approx 74 grs, which is two grains over Nosler max load IIRC with a 115 nos Bt BUT the bearing surface on the Bergers is far less. It is not a trick just all things working well together. Shortest barrel ,24", is getting 3550, longest, 28", is getting 3685 at 85 degrees. Things are a bit slower in cool weather. We used two different chronographs and we know these are real velocities. Must add we have a pacific tool and gauge reamer too.

We did try RL-25 with 100 gr bullets, RL-22 is a better choice.

 

[Bob33]

AZShooter - why do you say R22 is better than R25 with 100 grain bullets?

 

[jayran]

BOB, have you tried H-1000? when i was testing through my gun it worked better with the barnes. I went with the 115 bergers because they shoot awesome, through my gun.

 

[Bob33]

I've tried H1000 with 110g Accubonds, but not the TSX (it shot well with the NAB). The TSX and TTSX shoot very well for me with R22: right at 3600 with sub MOA consistency. I really can't see a compelling reason to try anything else, but the R25 experience of a friend sounded interesting so I am researching that. Thanks.

 

[AZShooter]

Why RL-22 with a 100 grainer? The burn rate is a tad faster and gave more velocity for me. I have read that many guys on 24 hr use RL-22 for 100s too.

 

[Bob33]

AZShooter, I also use R22 but the reason I asked about R25 is because my friend is getting more than 100 ft/second faster velocities with it by using three more grains (75). The question I have is how safe it is compared to 72 grains of R22.

 

[Iron Worker]

How safe is it? You'd have ample warning signs of too hot of a load before it turned your rifle into a bomb. Load one round at 71grs another at 72,then 73 and a few at 74 and check for pressure signs. I shoot a 6x284 and 22-250 AI and I exclusively load full throttle loads for those bad boys because that's why I wanted them. In 22-250AI I burn Re#22 others have suggested IMR 7828. But in my 6x284 it loves H4350 . I've tried the slow burners they're very accurate but a 100 FPS slower.

 

[Long Time Long Ranger]

I tried many powders and magpro with the 100 barnes tsx was the best in the rifle I tested. 1" group at 1/4 mile at over 3800 fps. Standard mk 5 with 26" barrel.

 

[gunnut]

Can you gents share COL of the loads you're using with 100 gr TSX and possibly any COL of 110 accubonds that you may have tried?

I'm using 69.5 grs R22, most accurate in recent Nosler manual and 3.260 OAL. First group with the rifle was 3/4" and shot this weekend and groups were like 2"+. Wonder if the first time was a fluke. Gun has only about 30 rounds total through it.

Stoney point shows 3.660 to "touch lands" so I'm jumping bullet right at .400. Have read posts where guys say to "seat short" which I'm assuming is 3.170 range like factory Weatherby loads and others are saying 3.30 or longer. I can easily get to 3.4+ COL and still keep over .250 of bullet in the case.

Any advice/help would be much appreciated! I've got 35 years of loading experience but this is my first Weatherby caliber and freebore is a new experience for me!

Gunnut

 

[Hired Gun]

Those are my loads on Reloaders Nest. I seat all my .257Wby loads to 3.3" except for the 75 grain V-Max. That bullet is so short I load it to 3.150" That is also my most accurate 257Wby load. You wouldn't believe if I told you how tight it shoots. At 3.3" they still feed from the magazine box in my Accumark. The distance to the rifling doesn't seem to make much difference. The barrel supports the bullet real well until it engages the rifling so it's not like it's really making an unsupported jump. The long length give a little more case capacity to work with.

With 100 grain triple shocks you shouldn't have much trouble getting 3700fps with RL25 or IMR-7828 in a 26" barrel. Just don't expect your primer pockets to stay very snug for long. I shoot 100 grain Partitions at 3600 and the primer pockets are doing very well. The TSX has a lot less bearing surface so it gets the speed a little easier. At 3700 they usually deposit the petals right under the skin of most critters out to about 350 to 400 yards.