Varget vs TAC for 77 smk loads

[alan98]

I have a ton of Varget and usually just use that for my 77SMK loads. I'll be getting a new Compass lake chamber Krieger barrel to try out and was thinking of trying some TAC as well for load work. Is there any benefit to using TAC? I know it's popular but I've just never tried it. 18" Mk12 Mod1..just looking for anyone that compared the two.

Alan

 

[ksthomas]

Alan98,

Varget and RL15 have been the "go-to" powders for HP-XC competitors for many years now, and for very good reason; they both work superbly. They give about equal velocities and accuracy, and I'd hazard a guess that if you walked the line at Camp Perry (or any other High Power match, for that matter) you'll find at least 90% of the shooters using one or the other. Believe me, if TAC had some advantage there, that's what we'd be using. No point in reinventing the wheel, especially if you have a good supply of Varget on hand.

 

[Hummerdawg]

The advantage of TAC is it meters well out of a Dillon powder measure if that's not an issue in your loading operation I would use the Varget

 

[1lnbrdg]

After shooting Varget for years, 3 years ago I started using Tac. I haven't looked back. And yes, I was 1 of the people on the line at Camp Perry that was shooting Varget or H-4895.

I had bought the Tac several years ago to try but had some temp issues with on my 1st outing with it. After several years, I went back and tried it again not trying to hit the top end, just a good middle ground load. It has shot well without pressure issues 30 deg to 101 deg temps, same load.

Either works good. Tac just seems to be easier for me to make consistant thrown short-line loads. Now, just wish I could find 8lbs.

 

[alan98]

Thanks for the replies. I have enough Varget for a longggg time so I'll just stick with that. I only load single stage with bushing dies and Chargemaster as well so I don't need a good throw powder.


Alan

 

[downlow]

Alan98,

Believe me, if TAC had some advantage there, that's what we'd be using. No point in reinventing the wheel.

It DOES have an advantage if your rifle won't shoot with Varget, and hammers with TAC.

 

[ksthomas]

Sort of like M14/M1As that don't shoot 4895, if you've got an AR that doesn't shoot 77s with Varget, there's a gun problem there.

 

[redneckbmxer24]

I stopped using Varget in gas guns because I like to load them through my Dillon and Varget meters like shit. I was using RL15 and ran out and just got a few pounds of 2000MR I'm going to try out. It's also a ball powder. I've never messed with Tac but if it meters well and the burn rate is right I wouldn't hesitate if that's what I had at the time.

 

[KUSA]

TAC is so much better than Varget for 77 smk. Varget simply can not produce the velocity that TAC can. Read JPs website. It's what they recommend.

 

[downlow]

Sort of like M14/M1As that don't shoot 4895, if you've got an AR that doesn't shoot 77s with Varget, there's a gun problem there.

Sort of like when you get a shitty batch of brass and the rep won't stand behind the product.

No problem with the gun when it shoots well with another component.

 

[downhill]

Velocity doesn't always equate with accuracy. See what the high master and master class shooters run. I'll bet you'll see a lot of varget and RL15 and very little TAC. +1 on the Varget.

 

[KUSA]

Velocity doesn't always equate with accuracy. See what the high master and master class shooters run. I'll bet you'll see a lot of varget and RL15 and very little TAC. +1 on the Varget.

I don't get the love for Varget. None of my rifles love it. They do love RE15. My ARs love TAC. I would gladly trade every pound of Varget for TAC.

 

[scudzuki]

I never got 77 SMKs to shoot worth a crap with TAC.
Even my new Krieger 24" match chambered barrel shot like crap (1.2 MOA) with TAC.
Switched to IMR 4895 and it's a consistent .6 MOA shooter.
Velocity is not as good, though.
I know TAC is popular in .223, but I only use it for plinking ammo.

Joe

 

[George63]

powder that meters well and works well with 77's is 8208

 

[downlow]

I never got 77 SMKs to shoot worth a crap with TAC.
Even my new Krieger 24" match chambered barrel shot like crap (1.2 MOA) with TAC.
Switched to IMR 4895 and it's a consistent .6 MOA shooter.
Velocity is not as good, though.
I know TAC is popular in .223, but I only use it for plinking ammo.

Joe

Every rifle is different. That's the beauty of experimenting. Eventually, if you have a well built rifle, you will find a hammer load. It's up to you to find it...

 

[scudzuki]

Every rifle is different. That's the beauty of experimenting. Eventually, if you have a well built rifle, you will find a hammer load. It's up to you to find it...

Of course.
I tried TAC with 4 different barrels, tried ladders and OCWs, and never got any of 'em to shoot sub MOA consistently.
I have since developed loads for 3 of those barrels (aforementioned Krieger, DD 18" S2W profile, and an AR Performance Melonited 16" "Recon" profile) that shoot consistent sub MOA with I4895.
TAC got me good velocity for plinking ammo but not good accuracy with match bullets, that' my experience.

Joe

 

[bruddah]

I've had some VERY good groups with TAC and SMK 77gr pills (sub 1/2 MOA).

I just decided to switch to Varget and 8208XBR since they are more temperature stable.

 

[KUSA]

I've had some VERY good groups with TAC and SMK 77gr pills (sub 1/2 MOA).

I just decided to switch to Varget and 8208XBR since they are more temperature stable.

Tell me about your personal troubles with temperature instability with TAC.

 

[bruddah]

Tell me about your personal troubles with temperature instability with TAC.

I haven't had any because I only used it once for a load work up.

Are you saying it is as stable as Varget or 8208XBR? Right now it is below freezing. During the summer months it can get up to 100F. I'd prefer no kaboom if I work up a hot load during the winter.

 

[Sendero_Man]

Win. 748 works and meters great with the 77 smk and 75 Amax

 

[KUSA]

I haven't had any because I only used it once for a load work up.

Are you saying it is as stable as Varget or 8208XBR? Right now it is below freezing. During the summer months it can get up to 100F. I'd prefer no kaboom if I work up a hot load during the winter.

I've shot a hot load of TAC on cold days and hot days and it works just as good one day as another. This is in a match chamber with 24.3 gr pushing a 77smk.

 

[KUSA]

Most of this temperature instability is internet bullshit that keeps getting puked up over and over.
For your reading pleasure. FAQ « Ramshot
[h=3]5. What is the real story behind temperature stability?[/h]Most of our powders are not insensitive, and will show some effect at hot and cold temperatures.
However, we test at -40F and +125F and the deviation in most cases are ca 3% to 5% at these extreme levels. Therefore most shooters do not notice much difference under normal practical hunting conditions.
More elaboration on the subject:
Complete temperature stability can only be achieved with tubular extruded powders designs, either with double base (NG) and/or with other coating technologies.
Because the ballistic performance at extreme temperature is completely dependant on the specific combination, it is very difficult to quantify and qualify.
Our standard powders perform very well at extreme temperatures, and usually pass the strict military requirements by a large margin.
This is a subject that often fraught with misconceptions and inaccuracies.
The term is used loosely by manufacturers without qualifying the subject, and is obviously exploited for marketing purposes and perceptions.
The facts are:

• Although powders can be improved, it’s really only possible with advanced coating procedures and additives which increase the cost.
• A particular powder can be improved re temperature stability for certain combinations, within a certain envelope which is specific to the following three main parameters/aspects
  • The caliber.
  • The weight of the projectile/bullet.
  • The performance level.

If any of these parameters/aspects go beyond or outside the intended ratio/s, the results will change and the performance will sometimes be different.
It is also very important that when a comparison is made, that all conditions re weapon i.e. components primer, case, bullet and the velocity are equal, and preferably done at the same time on the same day.

 

[bruddah]

I've shot a hot load of TAC on cold days and hot days and it works just as good one day as another. This is in a match chamber with 24.3 gr pushing a 77smk.

Most of this temperature instability is internet bullshit that keeps getting puked up over and over.
For your reading pleasure. FAQ « Ramshot
[h=3]5. What is the real story behind temperature stability?[/h]Most of our powders are not insensitive, and will show some effect at hot and cold temperatures.
However, we test at -40F and +125F and the deviation in most cases are ca 3% to 5% at these extreme levels. Therefore most shooters do not notice much difference under normal practical hunting conditions.
More elaboration on the subject:
Complete temperature stability can only be achieved with tubular extruded powders designs, either with double base (NG) and/or with other coating technologies.
Because the ballistic performance at extreme temperature is completely dependant on the specific combination, it is very difficult to quantify and qualify.
Our standard powders perform very well at extreme temperatures, and usually pass the strict military requirements by a large margin.
This is a subject that often fraught with misconceptions and inaccuracies.
The term is used loosely by manufacturers without qualifying the subject, and is obviously exploited for marketing purposes and perceptions.
The facts are:

• Although powders can be improved, it’s really only possible with advanced coating procedures and additives which increase the cost.
• A particular powder can be improved re temperature stability for certain combinations, within a certain envelope which is specific to the following three main parameters/aspects
  • The caliber.
  • The weight of the projectile/bullet.
  • The performance level.

If any of these parameters/aspects go beyond or outside the intended ratio/s, the results will change and the performance will sometimes be different.
It is also very important that when a comparison is made, that all conditions re weapon i.e. components primer, case, bullet and the velocity are equal, and preferably done at the same time on the same day.

Do you feel the same way about velocity changes when shooting out to 1,000 yds and beyond? (30 caliber). Wouldn't even the smaller velocity fluctuations cause more vertical stringing at extended ranges? The site says:

"Therefore most shooters do not notice much difference under normal practical hunting conditions".

I would venture to guess 500 yds out to 1,200 or more are not practical hunting conditions where velocity fluctuation might come into play (30 caliber weapons). Obviously the .223 is not going to be pushed out to the ranges a 30 cal will see. However I would still hesitate to work up a load that is on the hot side (at max or near max pressures) in mid winter and then fire that same load on a 90 degree day.

 

[KUSA]

Do you feel the same way about velocity changes when shooting out to 1,000 yds and beyond? (30 caliber). Wouldn't even the smaller velocity fluctuations cause more vertical stringing at extended ranges? The site says:

"Therefore most shooters do not notice much difference under normal practical hunting conditions".

I would venture to guess 500 yds out to 1,200 or more are not practical hunting conditions where velocity fluctuation might come into play (30 caliber weapons). Obviously the .223 is not going to be pushed out to the ranges a 30 cal will see. However I would still hesitate to work up a load that is on the hot side (at max or near max pressures) in mid winter and then fire that same load on a 90 degree day.

Check out the powders used in the popular match grade factory 308 ammo. I think you will find it is not Varget in it but rather a double based ball powder that will make your rifle go kaboom on a hot day .

 

[leid]

bruddah,
You and I are on about the same page at this point. The 77gr. SMK over 5.56MM pressure TAC shoots fine at around 0.5 MOA in good conditions; I have been using it since around 2006. But TAC is pretty much a typical double based powder in that it is thermally sensitive, looks like to the tune of 0.8 FPS/1 degree F from -10F to +135F in the 18" barrel I now use. Several shooters in our group, including myself, used the 77gr. SMK over 5.56MM pressure Varget for years prior to using TAC and accuracy with almost absolute thermal stability were there with Varget. But when the factory MK 262 MOD 1 cartridge became widely available, we found it was almost 150FPS faster than our Varget load due to the non-canister spherical double based propellant used. Most of us were using 24" or even 26" barrels at that time so low MV was not an issue using Varget. But when using an 18" barrel, the Varget loads were getting a bit on the puny side. We then worked up a 5.56MM pressure TAC loading modeled after the factory BHA MK 262 loading which shot quite well. Another propellant that several people above have mentioned & is worth testing with is H4895. It is almost as thermally stable as Varget but has the potential to get MV up to within 85 FPS of the MK 262 cartridge which is a very accurate MV in this 18" barrel. Although I have not had a chance to do a full work up using 8208 yet, it is top of my dance card for after the hunting season ends. Initial tests with 8208 indicate it may give up just a very slight amount of thermal stability as compared to Varget or H4895 but MV is just as high as with H4895 with better ES/SD numbers to help control vertical stringing at medium to LR. The bad news is you are pretty much on your own with 5.56 pressure loadings of 8208 as very little 5.56MM loading data is out there yet. My choice between H4895 or 8208 in 77gr. SMK & over-mag-length 80gr. VLD accuracy loads for this 18" barrel will be based on the actual MV/ES/SD/accuracy seen. Thermal stability should not be an issue with H4895, Varget, or 8208 so your thinking is sound IMO. .02

 

[bruddah]

Check out the powders used in the popular match grade factory 308 ammo. I think you will find it is not Varget in it but rather a double based ball powder that will make your rifle go kaboom on a hot day .

You addressed one small part of my question. Additionally, I'll bet the "match loads" aren't at the top end of the pressure spectrum on a 20F degree day, so yes, there is room for pressure to build during the hotter summer months without going Kaboom.
You act like I pissed in your cornflakes by saying I switched to Varget, 8208 XBR. If you go back and read, I did say TAC provided one of THE most accurate loads in my .223/5.56 AR with the 77gr SMKs. I chose to go with the extreme powders because of the safety (if I HAPPEN to be at a max pressure load during the winter work up, AND because I was taking my SPR to a class where we were engaging targets out to 800+ yards with our AR15 special purpose rifles). Additionally, it was 105 degrees all three days out there in the desert, and the ammo got a hell of a lot hotter than that if the sun happened to be hitting it. The black magazines don't help the situation at all either as they really soak up the heat from the sun.

bruddah,
You and I are on about the same page at this point. The 77gr. SMK over 5.56MM pressure TAC shoots fine at around 0.5 MOA in good conditions; I have been using it since around 2006. But TAC is pretty much a typical double based powder in that it is thermally sensitive, looks like to the tune of 0.8 FPS/1 degree F from -10F to +135F in the 18" barrel I now use. Several shooters in our group, including myself, used the 77gr. SMK over 5.56MM pressure Varget for years prior to using TAC and accuracy with almost absolute thermal stability were there with Varget. But when the factory MK 262 MOD 1 cartridge became widely available, we found it was almost 150FPS faster than our Varget load due to the non-canister spherical double based propellant used. Most of us were using 24" or even 26" barrels at that time so low MV was not an issue using Varget. But when using an 18" barrel, the Varget loads were getting a bit on the puny side. We then worked up a 5.56MM pressure TAC loading modeled after the factory BHA MK 262 loading which shot quite well. Another propellant that several people above have mentioned & is worth testing with is H4895. It is almost as thermally stable as Varget but has the potential to get MV up to within 85 FPS of the MK 262 cartridge which is a very accurate MV in this 18" barrel. Although I have not had a chance to do a full work up using 8208 yet, it is top of my dance card for after the hunting season ends. Initial tests with 8208 indicate it may give up just a very slight amount of thermal stability as compared to Varget or H4895 but MV is just as high as with H4895 with better ES/SD numbers to help control vertical stringing at medium to LR. The bad news is you are pretty much on your own with 5.56 pressure loadings of 8208 as very little 5.56MM loading data is out there yet. My choice between H4895 or 8208 in 77gr. SMK & over-mag-length 80gr. VLD accuracy loads for this 18" barrel will be based on the actual MV/ES/SD/accuracy seen. Thermal stability should not be an issue with H4895, Varget, or 8208 so your thinking is sound IMO. .02

Thanks leid.

 

[Thumper580]

For whatever reason I have never gotten good accuracy out of my target AR with Varget..... With IMR4895, TAC and 8208 it shoots amazing, 1/4" to 3/8" groups with 73 gr and 77gr bullets. TAC burns right next to 8208 and both meter like sugar. I think folks would agree that a max winter load would obviously be pushing the pressure envelope in the heat of the summer. Adjustments would just make sense. This whole temperature insensitive thing is "confusing/misleading" considering there is a built in safety factory in every reloading manual. How "max" over the limits are people reloading these rounds to???

 

[pmclaine]

All good info, thank you.

Im prepping .223 brass right now for my first reloads in that caliber.

I have 3K Nosler CC 77's, XBR8208, TAC and CFE 223 on hand hoping to get a good load for 16 inch LMT with one of those powders.

I also have Varget and 4064 in inventory but Im thinking those better suited to .308 and 30-06 needs.

Tagging for further wisdom that may drop on this posting.

 

[KUSA]

You act like I pissed in your cornflakes by saying I switched to Varget, 8208 XBR.

Sorry about the emotion but I love TAC and talk against it is like heresy.
There is no doubt that Varget is a great powder for temperature and accuracy. However I don't see it having any advantage using it over TAC in 223 using 77s. You probably won't be using it for 1000 yard shots so vertical variances are not an issue to me. Really your dope is going to be a little different each day due to other factors anyway.
And also what does the outside temperature matter when a round goes in a hot chamber? It's going to be hotter than hell instantly.
I have 8 pounds of Varget left that I don't use. I wish someone in eastern NC had some TAC they wanted to trade ftf. I'm done with my rant. Have a Merry Christmas.

 

[leid]

The perfect .223/5.56MM propellant has not been manufactured yet IMO. Each propellant has it strengths & weaknesses so choosing a .223/5.56MM propellant will most probably involve compromise. You can look at good loading manual data & come away with a pretty good idea of expected MV/pressure with a particular load. But at present, it appears that the actual thermal stability of a loading is something we are going to have to measure on our own as we develop loads in our individual rifles. Some of the canister grade powders we now use appear to be almost immune to OAT (outside air temperature) swings we might see in a year of shooting while others are not nearly as thermally insensitive. The burn rate of a propellant changes with temperature. And it does not matter whether the propellant's temperature was generated by OAT, an overheated barrel, or by cartridges being exposed to the summer sun. I have a freezer and a heating pad within 30 feet of my chrono in order to test my own loads for thermal stability while working them up. All 5.56MM loads tested used new/never-primed/never crimped LC 09 5.56MM brass, same lot #41 primer, same lot powder, all seated to same mag length COAL of 2.255" in Wilson Arbor dies. The hot/cold strings were run within minutes of each other with individual shots fired within seconds of being removed from the cooling/heating sources. Cartridges were single-loaded & fired with a bare minimum of chamber time (2-3 seconds). Barrel was allowed to cool between (5) shot strings with OAT around 70F. Cartridge temperature was verified using (3) thermometers, (2) mercury & (1) IR/laser. Bottom line: I followed the most stringent protocol of which I was capable for a DIY thermal stability test. But I am just a fellow shooter, however. There is a hell of a lot I just do not understand yet. .02.



MV listed below is (5) shot average fired in 18" full heavy fluted 1x7.7 SS Krieger/CLE 5.56MM chamber barrel with rifle length gas system & M4 suppressor:



77gr. SMK over 5.56MM NATO pressure VARGET: (Virtually immune to thermal variation of 145 degree F. But MV is a bit slow as compared to H4895 much less
the TAC & AA2520 double based spherical powder loads)
+135: MV 2685
/-10F: MV 2684
__________________
1 FPS over 145 degrees F



77gr. SMK over 5.56MM NATO pressure H4895: (Pretty decent MV for a single based stick rifle powder especially when used in colder temperatures)
+135F: MV 2741
//-10F: MV 2737
_________________
4 FPS over 145 degrees F



77gr. SMK over MAX listed 5.56MM NATO pressure RAMSHOT TAC: This equates to 10.6" at 600yds. or 20.2" at 750yds. POI shift from -10F to +135F in this 18" barrel.
+135F: MV 2841 FPS
//-10F: MV 2723 FPS
_________________
118 FPS over 145 degrees F

 

[bruddah]

The perfect .223/5.56MM propellant has not been manufactured yet IMO. Each propellant has it strengths & weaknesses so choosing a .223/5.56MM propellant will most probably involve compromise. You can look at good loading manual data & come away with a pretty good idea of expected MV/pressure with a particular load. But at present, it appears that the actual thermal stability of a loading is something we are going to have to measure on our own as we develop loads in our individual rifles. Some of the canister grade powders we now use appear to be almost immune to OAT (outside air temperature) swings we might see in a year of shooting while others are not nearly as thermally insensitive. The burn rate of a propellant changes with temperature. And it does not matter whether the propellant's temperature was generated by OAT, an overheated barrel, or by cartridges being exposed to the summer sun. I have a freezer and a heating pad within 30 feet of my chrono in order to test my own loads for thermal stability while working them up. All 5.56MM loads tested used new/never-primed/never crimped LC 09 5.56MM brass, same lot #41 primer, same lot powder, all seated to same mag length COAL of 2.255" in Wilson Arbor dies. The hot/cold strings were run within minutes of each other with individual shots fired within seconds of being removed from the cooling/heating sources. Cartridges were single-loaded & fired with a bare minimum of chamber time (2-3 seconds). Barrel was allowed to cool between (5) shot strings with OAT around 70F. Cartridge temperature was verified using (3) thermometers, (2) mercury & (1) IR/laser. Bottom line: I followed the most stringent protocol of which I was capable for a DIY thermal stability test. But I am just a fellow shooter, however. There is a hell of a lot I just do not understand yet. .02.



MV listed below is (5) shot average fired in 18" full heavy fluted 1x7.7 SS Krieger/CLE 5.56MM chamber barrel with rifle length gas system & M4 suppressor:



77gr. SMK over 5.56MM NATO pressure VARGET: (Virtually immune to thermal variation of 145 degree F. But MV is a bit slow as compared to H4895 much less
the TAC & AA2520 double based spherical powder loads)
+135: MV 2685
/-10F: MV 2684
__________________
1 FPS over 145 degrees F



77gr. SMK over 5.56MM NATO pressure H4895: (Pretty decent MV for a single based stick rifle powder especially when used in colder temperatures)
+135F: MV 2741
//-10F: MV 2737
_________________
4 FPS over 145 degrees F



77gr. SMK over MAX listed 5.56MM NATO pressure RAMSHOT TAC: This equates to 10.6" at 600yds. or 20.2" at 750yds. POI shift from -10F to +135F in this 18" barrel.
+135F: MV 2841 FPS
//-10F: MV 2723 FPS
_________________
118 FPS over 145 degrees F

That speaks a lot of H4895 as well. Didn't know it was so insensitive to temperature.

I'll have to tuck that info away for future reference.