6xc with 8208/Varget/R15/Ar Comp/4166

[urbanrifleman]

It seems that for the 6xc and the 105/115 range bullets the consensus is that H4350 or R16 is the FASTEST powders that are appropriate (and we get only slower from there). Just in the very short period of time I have been testing faster powders than these, the cartridge really seems to be happy with AR Comp, which would mean it would be appropriate with 8208, H4895, Varget, R15, Benchmark, etc etc.

I found this thread and based my loads on it. I was going to reply to this thread and bump it up but i decided to start a new one. I hope there are folks who want to discuss it.

6XC + Varget

Has anybody had success with varget in the 6xc?

forum.accurateshooter.com

My tests are just starting but I can see lots of potential.

 

[AckleymanII]

In one 31" unturned blank, 8T, .237 Bore, .147 FB, with R#17, Rem 7 1/2, Sierra 107, I got 4250 in a single bug hole with Gunsandgunsmithing Tuner. I actually had bug hole nodes at 3050, 3150, and 3250 using Lapua Palma brass. The node at 3150 was in the zero's, and the node at 3250 was just a hair over .100 three shot groups.

Fire cracking started within 400 rounds of using R#17, and I went back to H4350.

I was fortunate to find an 8lb'r of AR comp, will try that in the near future.

Varget, H4895, and R#15 can be difficult to clean the carbon out of the barrel, as they seem to cook the carbon on.

 

[mongo chicago]

I use Varget with the 87gr. Hornady Vax and am very satisfied. Not set up in the 6XC for heavier bullets.

 

[Idaho-Lefty]

RL-17 is some,.. "HOT Chit" and HARD, on Throats ! I've heard this from, SEVERAL Shooters, now !
I'm using, StaBall 65 in my 6 XC with, 95's and 108's as it's, slightly slower than, the 4350's and I'm getting GOOD, Groups,.. but, it's kinda, dirty !

 

[urbanrifleman]

I think the faster powders would be much easier on the barrel.

 

[urbanrifleman]

35.5 grains AR comp. Berger 108.

Tough day for testing but I believe this is the node area I want to be in.

 

[AckleymanII]

I will be trying AA2700 next, one of the coolest burning powders by Heat Index, we will see how loads change, shot kegs of it on p. dog towns in 95*-100* temps in 243,22/250 AI, and 243 AI.

When I necked down the Palma brass, I left the neck at a length of .400, and cut the neck in the chamber longer, and it sure cut down on the leade growth!

P.O. Ackley spoke of this lack of leade growth on long necks(interference point), but the talking heads, gun writers never mention it, so it goes the way of the Doo Doo Bird!

 

[WyleWD]

I will be trying AA2700 next, one of the coolest burning powders by Heat Index, we will see how loads change, shot kegs of it on p. dog towns in 95*-100* temps in 243,22/250 AI, and 243 AI.

When I necked down the Palma brass, I left the neck at a length of .400, and cut the neck in the chamber longer, and it sure cut down on the leade growth!

P.O. Ackley spoke of this lack of leade growth on long necks(interference point), but the talking heads, gun writers never mention it, so it goes the way of the Doo Doo Bird!

Where or how do I find this "Heat Index" on gunpowders?? I'm doing something wrong in my search because I can't find it. Any help you can provide would be very much appreciated. WD

 

[Kracken McGraw]

Where or how do I find this "Heat Index" on gunpowders?? I'm doing something wrong in my search because I can't find it. Any help you can provide would be very much appreciated. WD

This may be the thread that has it.https://forum.accurateshooter.com/threads/specific-heat-of-reloader-26.3929050/#post-37005592

 

[urbanrifleman]

I think as much as the heat index is the shear amount of powder that might be be responsible for smoking the throat.

 

[jlmurphy]

Most smokeless powders are single based, meaning they have been treated with nitroglycerin one time, double based powders are treated twice and have more energy. Many Reloder and Vihta Vouri 500 series powders are double based. More energy, higher velocities, much hotter barrels, hard on the throats, and usually temperature sensitive. The Hodgdon Extreme line of powders was created to minimize performance swings due to temps. That is why H4350 and Varget are so popular.

 

[spclark]

I started using IMR 8208XBR in 6XC w/Berger 105VLD’s then Hybrids soon after it appeared.

Bought some for trying in Palma loads, but one afternoon was prepping for a 6XC propellant face-off so loaded five rounds each @ three different charge weights & went to shoot.

That middle-weight charge showed lowest vertical @ 600 yards of any of the five propellants I’d brought that afternoon, about 2”. H4350 was next, almost tied with RL17.

The heavy charge (39 gn) showed sticky-bolt lift with the first round so the others got pulled.

 

[urbanrifleman]

I started using IMR 8208XBR in 6XC w/Berger 105VLD’s then Hybrids soon after it appeared.

Bought some for trying in Palma loads, but one afternoon was prepping for a 6XC propellant face-off so loaded five rounds each @ three different charge weights & went to shoot.

That middle-weight charge showed lowest vertical @ 600 yards of any of the five propellants I’d brought that afternoon, about 2”. H4350 was next, almost tied with RL17.

The heavy charge (39 gn) showed sticky-bolt lift with the first round so the others got pulled.

So you were about 37ish at the sweet spot?

 

[DocDoc]

Single base powders are based on nitrocellulose. Double base powders are nitrocellulose that has nitroglycerine added. Both types typically have retardants added that help control the burn rate and make is progressive.

 

[bullfrog]

My 6xc was <1/2 moa with H4350/RL16/RL17/H4831 but I could never get the velocity extreme spreads down to acceptable levels (about 1-1.5 moa vertical at 1000). Varget was even more accurate and had super low velocity variation. Nice round groups at long range. Still getting 3010 fps with 108gr bergers and zero pressure signs. Nice thing is the velocity window is very wide. 2/10 grain only changes velocity about 10fps.

 

[urbanrifleman]

My 6xc was <1/2 moa with H4350/RL16/RL17/H4831 but I could never get the velocity extreme spreads down to acceptable levels (about 1-1.5 moa vertical at 1000). Varget was even more accurate and had super low velocity variation. Nice round groups at long range. Still getting 3010 fps with 108gr bergers and zero pressure signs. Nice thing is the velocity window is very wide. 2/10 grain only changes velocity about 10fps.

This was my madness in going to the faster powders. Much easier to get small spreads.

 

[urbanrifleman]

Ar comp second load workup. Went from 34.5 to 36.5 to be on the low end of the scale.

Charges are in the columns. Then going up in charge going right. Sadly, conditions turned bad at 36.5 at the far right side.

Well conditions were bad for the whole test, but really bad for the last column.

 

[urbanrifleman]

Btw this is VIRGIN 6XC Peterson brass right out of the bag.

 

[Lone Hunter]

Btw this is VIRGIN 6XC Peterson brass right out of the bag.

View attachment 1260101

What Grain bullets are you using with these charges?

 

[urbanrifleman]

What Grain bullets are you using with these charges?

108 Bergers