131 Blackjack vs 135 Berger

i built a 25 Creedmoor/ Brux barrel 7 1/2 twist i call a 257 Creedmoor i posted a lot of information about this fine cartridge on 24 campfire in the long range forum . i used all 3 bigger 25 caliber bullets >131 gr. Black jacks , 128 Hammer bullets and the 135 gr. Berger bullets . i also had custom dies made by Whidden for the 257 Creedmoor too and that made a big difference in accuracy , price was not that bad on the dies either.
i also built 2 - 257 Roberts /7 1/2 twist for hunting both shoot excellent. i ordered a Brux barrel ,#4 contour ,7 1/2 twist , will be finished at 28 inches and chambered in a 257 Weatherby mag. and put on a Weatherby mag. mark 5 action should be a great long range rifle for hunting probably use the 128 gr. Hammer bullets , hope too make close to 3400 fps ? Twolf
How did the 128 HH fly in the 1:7.5" 25 CM? I thought about the 128, but my 25SST is a 1:7.5", and Hammer states 1:7" minimum twist. So I just push the 121 @ 3414fps instead.

How much testing have you done with the 135 LR Hyb so far?
 
Lance, if you want to try the 128s I'll send you some to fling. Who knows they may work at your altitude?

Ryan
 
Made it back out today and actually brought my LabRadar. I started with trying to find max pressure using N565 because I didn't reach it last time. From the last time my 58.0 grn loads looked promising so I loaded up a few of those to test accuracy. Results below.

N565 58.0grn - 3032fps
60.0 grn - 3070fps
60.5 grn - 3090fps
61.0 grn - 3124fps EJ mark there so
stopped.
For the accuracy test at 58.0 I adjusted COAL on the fly. Started at .002" jump and shot 2, ran the bullet in shot 2 and so forth. Both the .025" and .030" jumps gave me .142" and .063" groups respectively. Now I know they were just 2 shot groups so I'll revisit but looks pretty promising.
 
Just wanted to post this up if anyone was curious on how they compare. Overall they look pretty similar, with the BJ (on the small sample size I took) being ~.002" longer.
In my 25SST the CBTO measurement to the lands was 2.180" for both bullets. I have a ladder loaded up with N565 and the 135 I'm going to test this weekend. Loaded with a .002" jump COAL on the 135 Berger is 2.858". That would put the COAL at the lands right at 2.86". I'll post my results when I get back!
Seems like everyone is in the same boat with there 25 cal rounds. My son had to go to 135 Berger's in his 25 Creedmoor and said he didn't all that much difference
 
How did the 128 HH fly in the 1:7.5" 25 CM? I thought about the 128, but my 25SST is a 1:7.5", and Hammer states 1:7" minimum twist. So I just push the 121 @ 3414fps instead.

How much testing have you done with the 135 LR Hyb so far?
i really think the 25 caliber 128 hammer bullets are going to be a excellent hunting bullet that` s very accurate . i do have a 7 1/2 twist Brux barrel on my 257 Creedmoor 7 contour 28 inch barrel , also 2 - 257 Roberts have 7 1/2 twist brux barrels now too, but those 2 hunting rifles i have not done much test firing with yet ,been too dang hot . now the 257 Creedmoor i have shot alot i did have to order some custom Whidden dies because this cartridge nobody seems to yet make good dies but the Whidden bushing dies are consistent and my groups at 100 yards with 5 shot groups with 131 Black Jacks,128 hammers and the 135 Bergers all shoot under a 1/2 inch many times 3/8 - 5/16 all the time with Lapua brass that`s been weighed,neck turned and at least fired 2 times out of the chamber of this rifle . shooting at targets at 100 yards i feel these 135 gr. 25 caliber Bullets might be a 1/10 of an inch better maybe , will know more when i shoot farther out when it cools down.
 
Anybody here shooting 25 creed that could help me out with some questions? My velocities are way slow, pressuring out in the low/mid 2700s with LRP brass and h4350. Have some Peterson brass that I had to neck turn way down and some necked down hornady. Have some SRP brass coming to try as well but not convinced there is not something wrong with my methods or potentially chamber/barrel. Thanks
If you want to push the 25 CM, you will likely have the best results using Lapua SRP brass and RL26. I switched to Peterson SRP brass this year and had to back down since they pressure out around 2800 (RL26 and 565) while the Lapua would get me to 3000 (this is with the 131). I am shooting steel with this combo so the lower recoil/throat erosion is nice but give up a little wind drift. If I was hunting would stay with the Lapua/RL26 combo. I have been hunting with the 131 as well but with a little more powder capacity behind it.
 
just got done load developing my 25sst with the 135 berger. shot pressure from 57 to 61 grains of h1000. the 59, 59.5, and 60 charge were right on top of each other. decided to load 59 to 59.9 in .3 grain increments at .025 off the lands
25sst load develop.jpg


felt that was a great node so loaded 59.6 at .025 and shot at 400 and 500. both groups were under a quarter so we will call it good in less than 20 shots. Ready to see on game
 
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