25sst finally breaking it in

61.4 3246
61.6 3245
61.8 3258
62 3267
62.2 3294
62.4 3300
62.6 3300
62.8 3318
63 3331
63.2 3343

first pressure mark at 62.6 bolt lift little sticky at 63.2 quit there

In my 25SST with the 131 BJ's I'm getting 3334fps with H-1000 at 61.4gr at 58*. How many rounds do you have through the barrel now?
Before it was broke in I saw 3211 fps at 61.5 grs with H-1000 at 66* and saw a faint ej mark at 62gr/3236fps
H-1000 and n565 seem to have a similar burn rate, n565 being a tad bit slower. I have a few pounds of n565 but haven't had chance to test it yet. My barrel has 572 rounds through it now.




For those of you with more experience, is that node size standard? A spot that flat for almost a grain difference seems rare, from the data I've seen.

I've seen identical results in my 6.5SS, 25SST, and 270WSM. Nodes run about 20fps ES over a 0.8gr spread.
 
This was measured with a 1st gen magneto speed. I have noticed when I shoot over a lab radar it gives me an additional 15fps for the same charge weight with several cartridges. When matching up drops the lab radar has been dead on velocity wise and seems to give more accurate data when going off drops, but nothing wrong with the MS especially at a quarter of the price.
 
In my 25SST with the 131 BJ's I'm getting 3334fps with H-1000 at 61.4gr at 58*. How many rounds do you have through the barrel now?
Before it was broke in I saw 3211 fps at 61.5 grs with H-1000 at 66* and saw a faint ej mark at 62gr/3236fps
H-1000 and n565 seem to have a similar burn rate, n565 being a tad bit slower. I have a few pounds of n565 but haven't had chance to test it yet. My barrel has 572 rounds through it now.






I've seen identical results in my 6.5SS, 25SST, and 270WSM. Nodes run about 20fps ES over a 0.8gr spread.


63 rounds through it. I wish I was shooting in 60 degree weather. My avg day is like 98 with lots of humidity.
 
Yea it's been brutal lately trying to shoot anytime other than early morning or late afternoon with temps being 100+ everyday, but I prefer to pressure test during the summer.
Those 60* days I was shooting were back in January lol.
 
Validated a couple loads at 400 today. Getting closer.

4D115F4F-81B7-4F25-9C2F-5AA7D47B433A.jpeg 15AB0D39-B179-4A11-8C49-92ED8A6115D2.jpeg 780858AB-8CFF-4878-9C4D-F84832F8FD96.jpeg
 
Definitely looking good. What are your plans for yours? Mine is gonna be mostly a hunter. One I like to shoot and won't bother anybody recoil shy like my wife. I have to confess, I've got blackjacks and hammers but I've got a box of 100grn nosler bt's leftover from my old 25'06 that I'm gonna give a go for pure speed on coyotes too. Ive skinned my last coyote as far as I'm concerned so the bigger splat the better. If they hold together out of the 7.25" twist they should be volatile at top speed.
 
Finally got a chance to break in my 25 SST. Just going to start with 55 grains of H1000 to break in new brass. Shot once cleaned shot once cleaned and then 3 shots at 100 to zero. Here they are. Not a bad start. Gonna be a really fun gun to shoot.

View attachment 143837
Whats your barrel length? And have you tried Rl-23 or N570?
I think this will be my 2nd Sherman build
 
Old thread I know but do you need to jam the bullets for fire forming? Planning on using some 117gr Sierras I have with 4831sc.
 
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