In the early stages of developing a load for my Ultra Lightweigh Mark V 257WBY. I am gonna try the 115gr Barnes TSX bullet. I was looking at Barnes data and they show a max load of 67.5 gr. H-1000 at 3.17". The hodgon website shows the 115 Barnes TSX max load at 71.0 gr of H-1000 at 3.25". My questions is 0.08" enough to stuff 3.5 grains more powder in the case? Is Barnes saying seat the bullet deeper for more jump?
257 WBY 115gr tsx question
- Thread starter MT257
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Yes, that is what Barnes is suggesting. My buddy was told the same thing with his 6.5 CM with 127 LRX. I personally would start at .015"-.020" and see how it goes. Good luck!
Ed
So I'll need to find the lans with an OAL gauge then seat the bullet 0.15-0.20" deeper? But weatherbys have I believe 0.375" of freebore. I have seen the recommendations on Barnes sight where they suggest with 0.050" jump and working back in 0.025" increments do you do this with the desired charge or find the sweet spot then tweak the charge?
Yep, you need to find the sweet spot that your rifle likes. One of my .300 WSM sweet spot with 215 Berger is .160" off the lands. You'll need to find the best compromise between your COAL and CBTO.
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With Barnes Bullets more jump is usually better than less and they also seem to like being pushed at near max loads. I start at .04 off and seat deeper by .01 at a time in 3 round batches till they tighten up and I find the sweet spot. I don't want hunting loads that touch or are too near the lands anyhow. Don't want to pull a bullet unloading and too near the lands can cause pressure issues in real hot weather.
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The lands are gonna be tough to reach in the ULW. When starting with a new Mark 5 I always start at functional mag length and work from there. With the T/TSX that is usually a great starting point with plenty of jump.
Yea. I am sure I will not be able to reach the lands due to freebore. So in your past experience with a Mark V, your saying you seated the bullet so it fits in the magazine then seated the bullet deeper from there if need be?
That is correct. I have 3 ULW in wby cartridges right now and have had a dozen others and they have all shot TSXs sub moa usually very close to mag length. I usually shoot 100 grainers from the .257, but I have not had trouble getting the 115s to shoot well. I run RL22 and have fantastic results. It's not "temp stable" but for me doing all of my hunting not in AZ or TX it works great. I have not really noticed a problem with it until it gets over 85F, and when it's 85 I am usually running rigs for walleyes.
Have you tried h1000 ever with the 115? I am hoping to find a load with it as I seem to have an ample supply.
My left hand ulw in 257 bee much prefers 7828ssc with the 115 Barnes, it doesn't like 115 partitions no matter what powder I use, and 117 Horn grain bullets, to h1000 but that doesn't mean yours will not like it. The 7828 also produced great velocity as well as 3 shot 1 hole groups.
I do have a single pound of the 7828ssc, I may just have to give it a whirl too. Only reason I am hoping to find H1000 works is have have 13 pounds of the stuff. And don't have a 300 anymore to use it.
MT,
Not sure if you have any 110 Accubonds laying around, but myself and many others have had great success with the 110's and H-1000. Fwiw, I run RL-25 with 115 NBT's and Partitions out of my 257 Roy. RL-25 has provided both the best accuracy and speed with 115's in the 3 257 Roy's I've owned.
Not sure if you have any 110 Accubonds laying around, but myself and many others have had great success with the 110's and H-1000. Fwiw, I run RL-25 with 115 NBT's and Partitions out of my 257 Roy. RL-25 has provided both the best accuracy and speed with 115's in the 3 257 Roy's I've owned.
Yes I have a fair amount. I use those in the other 257wby. Just figured I would try and use some components with this new rifle that I most likely will never touch with the other one. The other 257 I have loves h4831sc but I am hoping to save that as I do not have as much of that on hand with the current situation of components available.
