Ram Shot TAC in .308

Kindo

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I’ve been in the process of trying to find a good deer/bear (maybe elk) round for my CA MPR 16” .308 but have struggled to find good velocities with bullet/powder/primer combos that are available.

I’ve been using IMR 4064 with decent results (right at MOA with 165gr TGK going 2570 with a good tight velocity spread but recently came into some Ramshot TAC.

Loaded up two test ladders and one was about MOA and the other was about .7 MOA all at the same POI as my 4064 pet load. I didn’t bring a chrono because I was more or less testing for pressure signs and it’s about 90 and humid here, and I just didn’t have it in me.

My question is: Who here has shot TAC extensively and what is your opinion on temp sensitivity? It was 87 here today and I was firing these towards the end of my outing so hot barrel, hot action….hot….everything. The rounds had also warmed to the ambient temps of where we were shooting.

Im hoping that I’m not getting my hopes up. This stuff meters like a dream and would’ve saved me a bunch of headaches since this gun has been a bit picky. I’m assuming the velocity should be comparable to my 4064 load per the load data I was checking.

Thanks for the input.
 

SDHNTR

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Aug 30, 2012
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It’s somewhat temp sensitive. Seen much better and much worse. I get about 2% ish change in velocities between about 45 and 80 degrees. That’s as extreme a temp range as I have tested.
 
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Kindo

Kindo

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Thanks for the quick response to this! While that is a significant change at longer ranges, did you notice the overall grouping open up as well? Did you experience any stringing? Any flyers?

Thanks again!
 

SDHNTR

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No, nothing out of the ordinary. I use it without issue but my typical load is a good 2 gr below max. Not gonna push it.
 

Weldor

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I use it in a 16" barrel sig cross, temp range from 25 to 100 here in AZ. Only thing I have seen is lower pressure at 25-45 temps shooting suppressed. I developed the load for temps 40 to 80. I keep my ammo in a cooler for range days when it gets hot early and usually quit before 80 degrees.
 

xsn10s

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May 3, 2022
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I've ran TAC in my AR15 and 308 Win PSS. I never took notes on velocity change during the heat with TAC. But recently at around 70 degree I get 2760 fps with a 168 ELDM and a max charge of 43.8 gr. That's with Nosler seconds brass and Remington 9.5 primers. They're sub half inch at 100 yards. I've ran them hotter with 175 SMK and CC's. But the 43.8gr doesn't show any pressure so I left it there with the ELDM's.
 

Weldor

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Supressed with150 gr. 16 " bbl. 78 degrees 2710 fps average 10 shot string. I get 2680 average with benchmark. Tac and bm are good with Sig
 
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Kindo

Kindo

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Thanks for the input everyone. I went ahead and snagged a few more pounds so I'm invested now. I'll be sure and follow up with a few tests I'm going to run over the coming months with the powder.
 
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I load my 308 with TAC and get good velocities and no issues hunting with it here in TN where temps are 20s-40s. It’s a great powder. I never can find Varget so I just load with TAC.
 
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Kindo

Kindo

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Just wanted to post a quick update in case anyone finds this thread helpful.

I’ve burned through about 100 rounds of TAC loaded .308 with 165gr Sierra TGK Gamechangers. I tested cold bore shots, hot barrel shots and chamber “cooked” rounds where I let a round sit in a hot chamber to warm up at various time intervals to check temp sensitivity.

I did not chrono all rounds but I did check the initial 20 or so. Last 5 I checked were 2646, 2651, 2646, 2643 and 2640. All shots from a 16” barrel with SiCo Hybrid attached with direct thread mount.

Temps ranged from 65 deg F to 95 deg F.

I did get ejector swipe marks at this charge on Norma brass but this was also my most accurate load. A few cases did show some flattened primers but the impact printed with the other rounds so who knows. Yellow target was 100yds and black target was 200. Still need to work on my trigger work to take me out of the equation.

If anyone wants to question the 200 yard “cherry picking” group, those other groups on the target were shooting from various rests and positions and simply show my lack of marksmanship!
 

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Rover31

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Jun 5, 2022
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I have done a fair bit of shooting and testing with Tac and .308.
It is not as stable as Varget but lets back up a bit and find something out.
What bullet are you shooting?
What distance are you shooting, min and max?
What is the temperature range you are wanting to "play" in?
Are you using a ballistics calculator? If so which one? Some have the ability to compensate for temp variability.
All of this comes into play. and depending on your answers temperature "stability" may not matter or it might.
 

Tx270WT

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Jan 14, 2021
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TAC is a decent 308 powder. Working up a load with a 130gr ttsx currently. Velocities sitting around 3200. If I can’t find varget, TAC is my second choice
 
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TAC is a decent 308 powder. Working up a load with a 130gr ttsx currently. Velocities sitting around 3200. If I can’t find varget, TAC is my second choice

I settled on a 308 load with 130 TTSX and TAC 3020 fps out of 22” barrel and spooky accurate.
 
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