Looking for starting range - Varget + 105 Barts Hammer

[Linko]

Hi, I am looking for a good starting range of Varget to run my Barts Hammer 105's

I have 7 1/2, cci 450, cci 400, WSR, GM205M and BR-4 primers

I was thinking to start at 31.0 of Varget

Also if someone knows the velocity window for this combo.

 

[Jeffrey Tooker]

Hi, I am looking for a good starting range of Varget to run my Barts Hammer 105's

I have 7 1/2, cci 450, cci 400, WSR, GM205M and BR-4 primers

I was thinking to start at 31.0 of Varget

Also if someone knows the velocity window for this combo.

I presume you are loading for 6 BRA. If it is for 6 BR 31.0 Varget is too high a starting point.

Jeffrey

 

[spclark]

I presume you are loading for 6 BRA. If it is for 6 BR 31.0 Varget is too high a starting point.

S'truth!

Depending on what batch of VarGet you're messing with, 31 grains in a 6BR can ruin cases quick with just one firing. Better to start at 29.0 or maybe 29.3 grains with those 105's seated maybe 0.030" off the lands, then work up.

And save the 400's & WSR's for fire-forming. The other four are better for match shooting.

 

[Gabe22BR]

Best to start at 29gr- work up ... 2920fps is where ya want to be..

 

[group therapy]

Hi, I am looking for a good starting range of Varget to run my Barts Hammer 105's

I have 7 1/2, cci 450, cci 400, WSR, GM205M and BR-4 primers

I was thinking to start at 31.0 of Varget

Also if someone knows the velocity window for this combo.

I was using 30.6 gr with br4's. shot REALLY well. try 4895 as well. as always, ymmv

 

[Linko]

Geeze, I forgot to mention this is a 6 Dasher. 29" bartelin

 

[spclark]

Geeze, I forgot to mention this is a 6 Dasher. 29" bartelin

OK, so start your workup @ 30.0 grains. You want to be near 3,000 fps in a 1:8 twist, maybe 2,950 in a 1:7.5.

 

[tclaunch]

32.4 gr Varget shot very good for me with 105 class bullets in a .237" Bartlein. 2980 fps, is very good place to be. .006" in the lands.

 

[Linko]

really appreciate the starting point advice and target fps for Varget.

I bought 300 Lapua 6BR cases. Had them hydroformed and been breaking in the barrel and fireforming those cases. have 100 more to fireform.

been trying Rem 7 1/2, CCI450, GM205M and BR-5 primers with some H4895 loads (30.0 - 31.0) while fireforming

I will start the Varget loads next. Figure between Varget and H4895 I should find a winning combination.

 

[spclark]

What kinda bearing surface length do those Hammers have? You shoot any other 105’s you can compare that particular dimension to? That one alone has the most significance when it comes to load profiling in a particular weight class, owing to how much force it takes to engrave the lands into the bullet jacket/core as bullets travel from case to muzzle; longer vs. shorter usually means less propellant for the long ones.

 

[Jet]

31.4-33.0 of Varget will get you what you are looking for in a Dasher. If you have a short Freebore start a little lower.

 

[Switchbarrel]

33.3 gr Varget gets me ~3030 fps using Lapua cases. Multiple barrels from different makers & different lots of powder. 103 Vapor Trails & 108 Bergers.
Some jumped, others jammed.

-Rick

 

[Linko]

What kinda bearing surface length do those Hammers have? You shoot any other 105’s you can compare that particular dimension to? That one alone has the most significance when it comes to load profiling in a particular weight class, owing to how much force it takes to engrave the lands into the bullet jacket/core as bullets travel from case to muzzle; longer vs. shorter usually means less propellant for the long ones.

This rifle is a Borden custom. Jim Borden chambered it for the 105 Hammers. I will have to check my notes for freebore dimension.

 

[brxbrad]

33.3 gr Varget gets me ~3030 fps using Lapua cases. Multiple barrels from different makers & different lots of powder. 103 Vapor Trails & 108 Bergers.
Some jumped, others jammed.

-Rick

Lapua Brass, 33.3 gr Varget, 105 Hybids, 32" 1:8 Brux Barrel in my BRX gets me 3020fps.
Shoots like a laser.....

 

[JEFFPPC]

Lapua Brass, 33.3 gr Varget, 105 Hybids, 32" 1:8 Brux Barrel in my BRX gets me 3020fps.
Shoots like a laser.....

Brad your right on, after over 20 brx barrels 33.4 Varget has been the load in all of them but two. I have also shot all but two well in the lands. I shoot mostly 26 in barrels, few at 28 and with 107 SMK velocity is usually 2975 to 2990.

 

[Linko]

Is everyone using CCI450 primers

I have a 30" Bartelin, will my expected velocity be between 2975 to 3020?

 

[JFrank]

Ya gotta test primers for yourself and then you’ll know the answer.
J

 

[JEFFPPC]

Brad your right on, after over 20 brx barrels 33.4 Varget has been the load in all of them but two. I have also shot all but two well in the lands. I shoot mostly 26 in barrels, few at 28 and with 107 SMK velocity is usually 2975 to 2990.

I tune ES with primers, it's never been 450s. Even before I started to pay attention to ES I never settled on 450s. Usually shot BR4s . I now have switched to 250M's in all 3 comp rifles. You need to test as per SPJ for yourself. And after testing I now weight pimers. I use to scoff at the idea. Live and learn....by doing is the best way.

 

[Linko]

I tune ES with primers, it's never been 450s. Even before I started to pay attention to ES I never settled on 450s. Usually shot BR4s . I now have switched to 250M's in all 3 comp rifles. You need to test as per SPJ for yourself. And after testing I now weight pimers. I use to scoff at the idea. Live and learn....by doing is the best way.

The reason I mentioned CCI450 was an article I just read from https://precisionrifleblog.com/2019/09/02/6mm-dasher-load-data/ showing the most common loads for PRS competitors using 6 Dasher.

the vast majority were:

Lapua brass
Varget
CCI450
32.3 - 32.5 grains

I have tried Varget and BR-4 so far. Plan another outing with BR-4 and GM205M this week.

my ES and velocity results with BR-4 are:

32.2 16.52
32.3 7.17
32.4 4.85
32.5 18.9

 

[JFrank]

@Linko To share an experience;

If you run an abbreviated ladder test with each primer under consideration you should find that one will shoot /group better than the others.
Preference is 3 shots each using colored Bullets ( sharpie) to test at the distance you’ll be shooting/competing at.