The 25 sst...up and running

CA48

Well-Known Member
Joined
Nov 18, 2009
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Location
Texas
As soon as I caught word of the 131 Black Jack coming out I couldn't resist. I gave Rich of Sherman Wildcats a call about having a Reamer made for a 25 SST and of course he had already got the the process started.

After the reamer was made by JGS, Rich sent it over to Adam Busse of Gunware. After Adam worked his magic, I got the rifle back around the first of January and have just now got to do some initial testing.

The cartridge is based on a SAUM case slightly shortened and has a slight amount of case taper removed with a 30 degree shoulder. Case length is 1.950"
The idea/goals behind the case design are to run high bc bullets seated long to get the bullet out of the powder column, fit in a standard short action mag, feed smoothly, and produce near magnum velocity's in a short efficient package. Along with staying just under PRS velocity limits with mild loads.

6.5 PRC 140 Berger, left 2.900"
25 SST 131 Ace, Right 2.900"
IMG_7003.PNG



Rifle Specs

Rem 700 S/A
Ptg bolt
Gre Tan Fluted FP assembly
Rock Creek no. 5 sporter, 8 flutes, 26"
Micro bastard
March 3-24X52 FFP
Murphy Ti rail
NF Ti rings
MPA Competition Chassis
Jewel Trigger

IMG_6904.PNG


I bought some ADG 6.5 SST brass from Rich and have been liking it much better than the Norma 6.5 SS brass, its more like lapua quality. Necks thickness is consistent as well everything else.

78 cases weighed
209gr- 212 ES 3gr

26 cases measured
1.944-1.949" ES .005"

To get down to 25cal I lube the inside and out of the neck and run through a forster FL die then cases are ready to be primed and loaded, pretty simple.

Out of the box brass is headspaced with about .0015" clearance and I have had no problems running full pressure loads on the first firing.

I have gone through about 25 pieces of brass testing it. One thing I've noticed with the tapered primer pockets is when they get loose they hold a primer much better and longer than a normal pocket.
After testing some brass till failure the case only lengthened .005" so they shouldn't ever need to be trimmed.

First ladder was done at 750yds 45* wanted to go further but the wind was blowing 17-20mph at 10clock. I was having to hold windage each shot so need to retest in better conditions as these were not ideal but needed to get the barrel broke in and brass formed anyway.
IMG_6998.PNG


The unmarked shot at the top was 62gr, after I shot 61.7 62 landed way at the top so I had to adjust down and reshoot 62, then shot 62.3 and 62.6.
H-1000
2.892" +.015"
Fed 210
131 Black Jack
26" 7.25 twist

56 2915
56.5 2934
57 2932
57.5 3003
58 3032
58.5 3033
59 3103
59.5 3142
60 3150
60.5 3170
61 3211
61.5 3242
62 3267 Shiny Ejector Mark
62.5 3298 -
63 3317. -
63.5 3317 Shiny Ejector Mark out of room for powder.

I started testing a few loads and forming brass until I put 112 rounds through the barrel then shot another ladder over the magneto speed w/ H-1000

56.3 3094
56.6 3113
56.9 3105
57.2 3128
57.5 3144
57.8 3166
58.1 3170
58.4 3180
58.7 3198
59 3215
59.3 3232
59.6 3248
59.9 3270 Shiny Ejector Mark
60.2 3280. -
60.5 3282. -
60.8 3306. -
61.1 3335. -
61.4 3334. -
61.7 3360. -

At this point I still had not encountered any bolt lift but stopped there.

More Testing
IMG_7002.PNG


62.3 h-1000
85*
+.015
3348 fps Ave 3344
3348 Es 11
3337

Tested 6 pieces brass it was good for 2 firings.

The next day it dropped to 38* so I ran 2 shots with this load over the chrono.
3357. Avg 3362 fps
3367. ES 10 fps

It dropped 47* and I gained 18fps?

IMG_7001.PNG

Wind was 10mph at 10clock
61.4 h-1000
38*
+.015"
3340
3317. Avg 3330fps
3333 ES 23

Brass was lasting 3 firings at these pressures.


IMG_7004.PNG

Wind was 10mph 10 clock
58gr h-1000
+.015
3170 fps
Brass will last a long time with this load.

IMG_7005.PNG





Didn't shoot groups past 100 with this one yet but it looks good over the chrono. Groups were about .5 Moa at 100
60.3 h-1000
3300 Avg 3295 fps
3289 ES 11 fps
3295

Brass was lasting 6 firings with this load.

Now that I had some rounds through the rifle I called a buddy and we went hog hunting. I didn't get to test out these bullets on game yet unfortunately. On the bright side my buddy shot a 190 lb sow with his .223 in the head from the sitting position at about 150yards. She had 18-20 piglets with her.
IMG_6970.JPG

IMG_7006.PNG


I'm pretty happy so far and still have some testing to do. Retumbo and RL-26 are next, 3400fps shouldn't be a problem. Would also like to try some Hammer hunters. Looking forward to testing in better conditions to, over the 3 days I was testing and hog hunting temps were from 28* to 87* and it was really windy.

I'm honored to test out the First and only 25 SST. This was built as a light weight long range hunting rifle. I have it in the Chassis for load development for now, turns out it's a good look in there :) I have a manners eh-1 with Curtis custom bm that I will put the action in eventually. At that point the scoped rifle will weigh around 9.3 lbs. In the Chassis right now it weighs 13 pounds. The more I shoot this rifle the more I like it. I will keep this thread updated as I continue testing.

As usual It was great working with Rich and Adam and I would like to thank them for their expertise and hard work. I'm Glad we are getting to put bullets on Steel now and get some hard data.
 

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Great job and posting Chase! I'm surprised you got that much velocity with H1000. Retumbo and RL26 will do even better and any of those powders should produce moderate prs loads. I wish you could find some N565. I think it would be a top powder in this case.
 
Thank you Rich. I was a little surprised to see H-1000 producing those velocity's to. I've been thinking about ordering some N565 for a few months now. I will look around online tomorrow and see if I can I can find some. I have some N570 and it shot well with mild loads in my 6.5SS but I never tested for top end velocity with it but probably to slow anyway.
 
Thank you Rich. I was a little surprised to see H-1000 producing those velocity's to. I've been thinking about ordering some N565 for a few months now. I will look around online tomorrow and see if I can I can find some. I have some N570 and it shot well with mild loads in my 6.5SS but I never tested for top end velocity with it but probably to slow anyway.
I think it would be too slow. If you find some 565, let me know
 
Winds were 30+mph yesterday so I did a pressure Test with N570 and RL26. I was a little surprised with 570, it should be a good option.

Temp 58*
2.877" +.015"
Fed210
N570

61 3259
61.5 3315
62 3320 C
62.5 3357 C slight primer flattening
63 3385 C Shiny EJector Mark slight primer flattening
63.5 3385 C EJector Mark slight primer flattening powder crunching while seating.


RL26
56 3232
56.5 3246
57 3263
57.5 3287
58 3274
58.5 3351 Shiny EM
59 3355
59.5 3382 Heavy EM, Flat Primer, bolt lift
 
Winds were 30+mph yesterday so I did a pressure Test with N570 and RL26. I was a little surprised with 570, it should be a good option.

Temp 58*
2.877" +.015"
Fed210
N570

61 3259
61.5 3315
62 3320 C
62.5 3357 C slight primer flattening
63 3385 C Shiny EJector Mark slight primer flattening
63.5 3385 C EJector Mark slight primer flattening powder crunching while seating.


RL26
56 3232
56.5 3246
57 3263
57.5 3287
58 3274
58.5 3351 Shiny EM
59 3355
59.5 3382 Heavy EM, Flat Primer, bolt lift
Nice work Chase. I'm not surprised by N570, we have had good results with it in some of our other similar chamberings. The only question was whether you could get enough in to max out pressure. I really think N565 will be good too.
 
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I'm still looking for some N565. Been testing the 58gr load of h1000 at 3170 fps. I've been using 12 pieces of brass and finally had to trim them after 7 firings.
I ran that same charge behind a 147 in my 6.5 SST when I did the initial testing on ADG brass and fired it 20 times and still going strong! I trimmed it once at 11 firings starting with .010" trim length.
 
Chase, I'm real glad you dove in headfirst on this 25 SST and gave the Blackjacks some air time.

Those speeds out of a short action with just moderate recoil instead of high... you could not get this level of ballistic performance without a lot more powder AND a lot more recoil.

I have a 25 SST sitting here in my gunroom's corner but I have been too swamped to go out and test it yet. Big meetings and presentations getting in the way, but those wrapped up Friday.

I will be thrilled if I can get 3300 fps on the money and find a node in that area. Mule Deer and Elk will be in trouble this fall.

Overall these groups are stellar especially considering they are coming from a #5 Sporter!

Please keep us updated. Your work will help inform the rest of us that come behind on our 25 SSTs.
 
I ran that same charge behind a 147 in my 6.5 SST when I did the initial testing on ADG brass and fired it 20 times and still going strong! I trimmed it once at 11 firings starting with .010" trim length.

It will make a good PRS load.


Chase, I'm real glad you dove in headfirst on this 25 SST and gave the Blackjacks some air time.

Those speeds out of a short action with just moderate recoil instead of high... you could not get this level of ballistic performance without a lot more powder AND a lot more recoil.

I have a 25 SST sitting here in my gunroom's corner but I have been too swamped to go out and test it yet. Big meetings and presentations getting in the way, but those wrapped up Friday.

I will be thrilled if I can get 3300 fps on the money and find a node in that area. Mule Deer and Elk will be in trouble this fall.

Overall these groups are stellar especially considering they are coming from a #5 Sporter!

Please keep us updated. Your work will help inform the rest of us that come behind on our 25 SSTs.

Glad to be putting in the ground work on this one! From what I'm seeing initially 3300fps won't be a problem.

It's been shooting well so far and groups should tighten up when I get a chance to shoot in better conditions. I originally wanted to use a Proof CF but I would have had to buy 10 minimum as a 1in 7.5 twist is not a standard option from Proof.

I'm still trying to get some bullets in hogs to see first hand how they do. Had a chance to go hunting yesterday but it was to windy for anything to be out.

Il be looking forward to seeing how your rifles compares. Also glad to hear you will be bringing out a even heavier hunting bullet. It would go great in a 25/300 Norma Imp.
 
It will make a good PRS load.




Glad to be putting in the ground work on this one! From what I'm seeing initially 3300fps won't be a problem.

It's been shooting well so far and groups should tighten up when I get a chance to shoot in better conditions. I originally wanted to use a Proof CF but I would have had to buy 10 minimum as a 1in 7.5 twist is not a standard option from Proof.

I'm still trying to get some bullets in hogs to see first hand how they do. Had a chance to go hunting yesterday but it was to windy for anything to be out.

Il be looking forward to seeing how your rifles compares. Also glad to hear you will be bringing out a even heavier hunting bullet. It would go great in a 25/300 Norma Imp.

A friend who is quite famous for making good shooting bags in Texas sent us a pic of these piggies who didn't like the ACE.

Wicked Exit Holes.

swine.png
 

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