6 ARC Powder for 90’s

[KMW 1954]

Now running with the 107smk 28.8 gr of lvr is magic. Spitting them out at 2740 fps, they are subsonic at just under 1400 yds. A viable long range small frame gas gun.

Been running 105gr Berger over 28.7gr LVR ina 28" Bolt rifle and getting around 2830fps.

Most of my shooting has taken place in temps of -15* to around +45* and it has been extremely stable. Even up to the rare occasions that I have shot it in 70* temps.
Overall the average temps are between 10* - 40*

 

[Shifty6br]

Been running 105gr Berger over 28.7gr LVR ina 28" Bolt rifle and getting around 2830fps.

Most of my shooting has taken place in temps of -15* to around +45* and it has been extremely stable. Even up to the rare occasions that I have shot it in 70* temps.
Overall the average temps are between 10* - 40*

Yes, I feel lvr gets more of a bad rep than it really is. My temp swings are in the very very extreme, we get some really humid and hot summers and it's those days I see the jump, even in some of my more stable powder cartridges it is there. So it can be expected I suppose, but I have not found it to be a deal breaker in any way.

I developed this load over some pretty hot days over the summer, I tried to get out on those days to put things in practice and from past test do not expect it spike beyond my current velocity.

I did try some Bergers and they were fantastic..I'm pretty sure I can get those to hit 2800...but I shoot those exclusively out of my 47L and didn't want to hurt his feelings..lol.. as well as the smk being a smidgen cheaper. If I was a richer man I would probably just do Bergers all around for everything.

 

[KMW 1954]

I did try some Bergers and they were fantastic..I'm pretty sure I can get those to hit 2800...but I shoot those exclusively out of my 47L and didn't want to hurt his feelings..lol.. as well as the smk being a smidgen cheaper. If I was a richer man I would probably just do Bergers all around for everything.

I use the Bergers because I am shooting in an informal target league at very small targets for score.

With the LVR I have been able to reach almost 3100fps with my 28" barrel but the groups opened up horribly, 1.5" at 100yds! Besides, I don't need to beat up my equipment like that.

 

[Shifty6br]

I use the Bergers because I am shooting in an informal target league at very small targets for score.

With the LVR I have been able to reach almost 3100fps with my 28" barrel but the groups opened up horribly, 1.5" at 100yds! Besides, I don't need to beat up my equipment like that.

Yowzers that is smoking!! Agreed...sometimes faster is not better.

 

[gunsandgunsmithing]

I use the Bergers because I am shooting in an informal target league at very small targets for score.

With the LVR I have been able to reach almost 3100fps with my 28" barrel but the groups opened up horribly, 1.5" at 100yds! Besides, I don't need to beat up my equipment like that.

Trying to follow here but not seeing it....Which berger bullet were you getting 3100fps and LVR with?

 

[KMW 1954]

Trying to follow here but not seeing it....Which berger bullet were you getting 3100fps and LVR with?

That was with the 105 hybrid. I believe the charge data was with either Hornady or Berger and was above their listed charge. Bullet was loaded very long and that charge and speed were worked up in .2gr increments from the 28.7 load I have been using and chrono'd with a MagnetoSpeed. Was also using Starline brass

Even at that charge and speed I was not seeing and pressure signs on the brass and was having normal pressure bolt lift. I quite the testing at that point because the group size had deteriorated so badly. I believe the actual recorded speed on the MagnetoSpeed was 3079 fps.

With this 28" Shilen 4groove barrel I am constantly seeing speeds 100+ fps faster than any published data states but then most of them are stating a 24" barrel

 

[gunsandgunsmithing]

That was with the 105 hybrid. I believe the charge data was with either Hornady or Berger and was above their listed charge. Bullet was loaded very long and that charge and speed were worked up in .2gr increments from the 28.7 load I have been using and chrono'd with a MagnetoSpeed. Was also using Starline brass

Even at that charge and speed I was not seeing and pressure signs on the brass and was having normal pressure bolt lift. I quite the testing at that point because the group size had deteriorated so badly. I believe the actual recorded speed on the MagnetoSpeed was 3079 fps.

With this 28" Shilen 4groove barrel I am constantly seeing speeds 100+ fps faster than any published data states but then most of them are stating a 24" barrel

That's definitely up there and enough to make a 6BR blush with embarrassment, as well as some Dashers! I'm not doubting you but I have to question the chrono or something. I've loaded a 6 Grendel to some crazy pressures but I can't say I've been quite there. 3100 with a 95, I can believe, easily, but that's still up there. 80's at 3400...way up there, but doable...Brass life, even with Lapua Grendel brass is not what I'd call even satisfactory though. So, I slowed them a bit to save brass. But boy did they shoot up there! But 105's at 3100 has to be crazy hot. That said, LVR has not given me good accuracy at higher pressures but does seem to make speed. So yeah...maybe so. Just crazy speed. Of course a Grendel and ARC are "almost" the same, with a small capacity edge going to the Grendel, but nothing I'd call substantial, at all. Maybe I gave up on LVR too soon. It might have a higher node but I simply can't remember if I pushed it as far as I could or not. Like you, the accuracy fell off for a long while when I felt like I was anywhere near top end with it. I'll play with it more soon.

 

[KMW 1954]

I think I have to attribute all this to the 28" barrel. As I said, everything is much faster than what I am told I should be seeing.

As for the accuracy of the chrono is anyone's guess but when compared to a couple others it appears stable.

When I did this I wanted to see how far I could push it so started loading up 3ea in .2gr increases. Looked tonight and can't find my notes with load data but I know the load I started at was Berger 105gr Target Hybrid, seated BTO @ 1.792", LVR 28.7gr, Remington 7.5 primers, Starline brass.

I'm thinking I was up around 30.0gr when I finished but I know it was not a compressed load, or at least not a heavy compressed load because I has no issue seating bullet. As I also recall I started seeing the groups opening up 3 loads before I stopped and again when it fell of that much I stopped as I figured I was just wasting components. I really expected to see swipe marks on the brass or a very heavy bolt lift but I seen neither.

I know we have chatted the pros and cons of the 6mm a few times and I believe what you tell me and we agree on many points. Though again I say, I shoot against a number of guys shooting some form of 6BR. None of them are running at or near max loads, mostly because the precision/accuracy is greater at lower speeds. They all seem to be loading with Varget. They are still all amazed that I am loading the same 105gr bullets with the LVR and achieving nearly the same speed they are in their BR's, and BRA's. Much larger spread against the Dasher.

 

[KMW 1954]

On a final note after sleeping on it, this 105gr 6mm Berger bullet must have a sweet spot in the 2850 - 2870 fps range because that seems to be were most everyone is running it regardless of how one gets there.