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Discussion Starter · #1 ·
Hi guys. I'm having a velocity issue with my reloads.... 120 SST, SSA brass, CCI #41 primers and AA2200 powder. Accurates reloading info calls 27.2 the max charge. 27.2 grain gave me a pathetic average velocity of 2,405 FPS (the factory ammo chrono'd an avg of 2,569). I went all the way up to 27.5 grains and only averaged 2,486 FPS (no pressure signs). I matched the factory ogive measurement for test 1, then loaded longer and shorter. I cannot break the 2,500 FPS barrier. Any thoughts??
 

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What barrel are you using?

27.2-27.5 gr 2200 is what most are using to get essentially factory velocity in a 16" barrel. Factory spec is 2460 fps in a 16". Load manuals generally show max for SAAMI loads.
 

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Hi guys. I'm having a velocity issue with my reloads.... 120 SST, SSA brass, CCI #41 primers and AA2200 powder. Accurates reloading info calls 27.2 the max charge. 27.2 grain gave me a pathetic average velocity of 2,405 FPS (the factory ammo chrono'd an avg of 2,569). I went all the way up to 27.5 grains and only averaged 2,486 FPS (no pressure signs). I matched the factory ogive measurement for test 1, then loaded longer and shorter. I cannot break the 2,500 FPS barrier. Any thoughts??
I had the same thing with my 16 inch ARP Barrel. I have tried to CFE powder and increased velocity quite a bit but have not done extensive testing yet
 

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Discussion Starter · #4 ·
The barrel is a factory stag barrel (1:11 twist). I would be okay with the speed if the factory rounds were traveling closer to the speeds i'm getting out of my reloads. It's pretty baffling. I would love to switch to another powder, but I have 24 lbs. of AA2200... so i'm exhausting my efforts here lol.
 

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The barrel is a factory stag barrel (1:11 twist). I would be okay with the speed if the factory rounds were traveling closer to the speeds i'm getting out of my reloads. It's pretty baffling. I would love to switch to another powder, but I have 24 lbs. of AA2200... so i'm exhausting my efforts here lol.
Guess that means 16" standard
 

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I would double check the vel. On the factory load that is one of the fastest vel. That I've seen anyone post in a 16" tube.Most reports around the mid 2400 range. 2500 fps in a 16" barrel is very good.
 

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Discussion Starter · #8 ·
Sorry... Yes it's a 16" barrel. So I fired 2 strings (10 shots each) of Hornady custom 120 SST. The first string averaged 2,569 FPS and the second averaged 2,566 FPS. BUT!!!!! If you guys think that this velocity is par for the course then I might be able to rest my weary head. Just a little amazed at the velocity of that ammo. What would you guys say the "normal" range is for the 120 SST out of a 16" barrel?
 

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Sorry... Yes it's a 16" barrel. So I fired 2 strings (10 shots each) of Hornady custom 120 SST. The first string averaged 2,569 FPS and the second averaged 2,566 FPS. BUT!!!!! If you guys think that this velocity is par for the course then I might be able to rest my weary head. Just a little amazed at the velocity of that ammo. What would you guys say the "normal" range is for the 120 SST out of a 16" barrel?
Other guys have stated a similar thing. Factory ammo much faster. 2450 range is pretty normal.
 

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I used 27.2gr AA2200 federal brass CCI 450 primer out of 16" bbl was getting avg 2542 fps.
 

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18" ARP Target Crown

AA2200 w/ CCI 41 and FC cases;
COAL - 2.294"

26.9 - 2491 fps
27.2 - 2507
27.5 - 2550 Most Accurate
27.8 - 2559

Very little to No signs of pressure in my rifle.........Use this data at your own risk.
 

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Check the bullet thread on this subject. I believe a lot of folks have had your same issue. Not really an issue though, I think. Just shows Hornady built a kick ass round for our caliber. It's been suggested they use powders unavailable to us. What's interesting to me in this is that their round can be fired in an old SAAMI chamber and it's still faster than our SPCII only handloads. I wonder how the H round would perform at SPCII loads.
 

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Discussion Starter · #16 ·
Check the bullet thread on this subject. I believe a lot of folks have had your same issue. Not really an issue though, I think. Just shows Hornady built a kick ass round for our caliber. It's been suggested they use powders unavailable to us. What's interesting to me in this is that their round can be fired in an old SAAMI chamber and it's still faster than our SPCII only handloads. I wonder how the H round would perform at SPCII loads.
It is a nice round. When i started reloading, I told myself that all i wanted to do was make a more accurate round AND match or exceed factory velocity. I guess i out of two isn't bad haha.
 

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Hi guys. I'm having a velocity issue with my reloads.... 120 SST, SSA brass, CCI #41 primers and AA2200 powder. Accurates reloading info calls 27.2 the max charge. 27.2 grain gave me a pathetic average velocity of 2,405 FPS (the factory ammo chrono'd an avg of 2,569). I went all the way up to 27.5 grains and only averaged 2,486 FPS (no pressure signs). I matched the factory ogive measurement for test 1, then loaded longer and shorter. I cannot break the 2,500 FPS barrier. Any thoughts??
same load as yours from 16" ARP at 2.290 2450. 27.5 gr got 2480 but that is maxed out. I don't think you will find a powder to get you there unless you cut your mags and go longer coal with Lever of CFE. even then you may not get there with a 16".
 

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same load as yours from 16" ARP at 2.290 2450. 27.5 gr got 2480 but that is maxed out. I don't think you will find a powder to get you there unless you cut your mags and go longer coal with Lever of CFE. even then you may not get there with a 16".
I think there will be some increase using cfe but we are limited by how much room the SST takes up. Hope to test in a few months.
 
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